Fosi Audio MC351 is a compact 2.1-channel integrated digital amplifier for passive stereo speakers and a passive subwoofer.Dual TI TPA3255 amplifier chips, broad digital and analog inputs and up to 165W × 2 + 350W at 4Ω make it a practical control center for powerful 2.1 systems.Why it stands outDedicated 2.1 amplificationSeparate stereo and passive-subwoofer amplification builds a complete 2.1 system without a second power amp.Dual TPA3255 architectureTwo TI TPA3255 amplifier chips provide high output for speakers and a passive subwoofer.Broad source compatibilityBluetooth 5.3, USB, optical, coaxial and RCA inputs cover common music, computer and TV sources.System expansion through pre-outThe pre-out connection supports a powered subwoofer or compatible downstream equipment.Best for
Passive bookshelf or floorstanding speaker systems
2.1 systems using a passive subwoofer
TV and desktop systems using optical, coaxial or USB audio
Users who need both wireless and wired source inputs
Not ideal for
Users needing HDMI ARC or TV-remote CEC control
Headphone-only systems
Turntables without a built-in or external phono preamp
EMiUZEK Buying Notes
MC351 directly powers passive speakers and a passive subwoofer; these are different from line-level active speakers.
USB is an audio-data input, not a power input.
RCA is line level and does not replace a phono preamp for a standard turntable.
Frequently asked questionsCan MC351 drive passive speakers?Yes. It is designed for 4–8Ω passive speakers.Can it power a passive subwoofer?Yes. It has a dedicated amplified passive-subwoofer output.Can I connect a powered subwoofer?Yes. Use the line-level pre-out with a compatible powered subwoofer.Does it support HDMI ARC?No. Use optical, coaxial or RCA audio from a television.What does the USB port do?It receives USB digital audio from a compatible computer or source; it does not power the amplifier.Can I connect a turntable?Only if the turntable has a built-in phono preamp or you add an external phono preamp.HOW TO CONNECT2.1 passive speaker systemSource: Computer, streamer or TVConnection: USB, optical, coaxial, RCA or BluetoothOutput: Speaker terminals + passive-subwoofer outputTarget: Passive speakers + passive subwooferNote: Match speaker impedance and begin with low volume.Stereo speaker systemSource: Any supported digital or analog sourceConnection: Chosen inputOutput: Left/right speaker terminalsTarget: 4–8Ω passive speakersNote: Leave the passive-subwoofer output unused for a 2.0 system.System with powered subwooferSource: Any supported sourceConnection: Chosen inputOutput: Speaker terminals + pre-outTarget: Passive speakers + powered subwooferNote: Set crossover and level on the powered subwoofer.Technical SpecificationsCore specifications
Feature
Specification
Product type
2.1-channel integrated digital amplifier
Amplifier chips
TI TPA3255 × 2
Maximum output
165W × 2 + 350W at 4Ω
Speaker impedance
4–8Ω
THD
≤0.03%
SNR / Dynamic range
≥100dB / ≥100dB
Power input range
DC 24–48V
Inputs and outputs
Feature
Specification
Inputs
Bluetooth 5.3, USB, optical, coaxial, RCA
Outputs
Passive speakers, passive subwoofer, pre-out
USB sampling
Up to 24-bit / 96kHz
Optical / coaxial sampling
Up to 32-bit / 192kHz
Frequency response
20Hz–20kHz (±0.5dB)
Subwoofer output range
20Hz–250Hz
Recommended System Setup
Setup
Connection
2.1 passive system
Source → MC351 → Passive speakers + passive subwoofer
TV system
TV optical output → MC351 → Passive speakers
Powered sub expansion
Source → MC351 → Passive speakers + pre-out → Powered subwoofer
Additional Product ContentFosi Audio product comparisonCompare the two compact Fosi Audio integrated amplifiers by their power, output structure and intended system layout.
Feature
MC351
MC331
Product position
High-power 2.1 digital integrated amplifier
Tube DAC / integrated stereo amplifier
Built-in speaker amplifier
Yes
Yes
Maximum output
165W × 2 + 350W at 4Ω
105W × 2 at 4Ω
Main inputs
Bluetooth 5.3, USB, optical, coaxial, RCA
Bluetooth, USB, optical, coaxial, RCA
Speaker output
Stereo passive speakers
Stereo passive speakers
Passive subwoofer output
Yes, dedicated amplified output
No
Line-level pre-out
Yes
Yes
Headphone output
No
Yes, 3.5mm
Tube stage
No
Yes, replaceable tubes
Best use
Powerful passive-speaker 2.1 system
Compact tube stereo and headphone system
Fosi Audio Music Rhythm Visualizer Light is a USB-C powered ambient LED display that reacts to nearby music through its built-in microphone.Its 32 RGB LEDs, adjustable effects and compact aluminum housing add synchronized visual movement to a desktop, gaming or HiFi setup without entering the audio signal path.Why it stands outReal-time music responseA built-in microphone converts nearby rhythm and level changes into synchronized LED movement.32 RGB LED displayMultiple colors and dynamic effects create a more expressive visual response than a static ambient light.Adjustable presentationOn-device controls allow quick changes to mode, color and sensitivity.Simple USB-C powerThe compact aluminum light can be powered from a suitable USB source without connecting to audio equipment.Best for
Desktop HiFi systems
Gaming and computer setups
Listening-room ambient lighting
Users wanting sound-reactive visuals without changing the audio chain
Not ideal for
Users needing an audio spectrum measurement instrument
Outdoor or wet-location lighting
Users expecting the light to transmit or process audio
EMiUZEK Buying Notes
The visualizer reacts through a microphone and does not need an audio input cable.
USB-C supplies power only; the light is not a DAC, amplifier or music source.
Performance depends on room volume, distance and sensitivity setting.
Frequently asked questionsDoes it connect to the audio output?No. It listens through its built-in microphone and does not enter the audio signal path.What does USB-C do?USB-C supplies power to the visualizer.Can I adjust the lighting?Yes. Use the controls to change the mode, color and sensitivity.Will it work with speakers and headphones?It responds best to audible room sound. Headphone-only playback may not provide enough sound for the microphone.Does it improve sound quality?No. It is a visual accessory and does not process audio.Is it a professional spectrum analyzer?No. It is an entertainment light designed for responsive visual effects.HOW TO CONNECTDesktop audio setupSource: Computer or streamer playing through speakersConnection: USB-C power; sound detected by microphoneOutput: RGB light displayTarget: Visualizer placed near the speakersNote: Adjust sensitivity to suit the listening level.HiFi listening roomSource: Amplifier and speaker systemConnection: USB-C power; ambient sound detectionOutput: RGB light displayTarget: Visualizer on a shelf or equipment rackNote: Keep the microphone unobstructed.Gaming setupSource: PC or console with speakersConnection: USB-C power; ambient sound detectionOutput: RGB light displayTarget: Visualizer near the display or speakersNote: Choose a lower sensitivity if effects remain constantly active.Technical SpecificationsCore specifications
Feature
Specification
Product type
Sound-reactive ambient LED visualizer
LED array
32 RGB LEDs
Sound detection
Built-in microphone
Processing
32-bit ARM processor with automatic gain control
Housing
Aluminum alloy
Controls and power
Feature
Specification
Power input
USB-C
Adjustments
Display mode, color, speed and sensitivity
Audio connection
Not required
Recommended System Setup
Setup
Connection
Desktop system
USB power → Visualizer placed near speakers
Gaming system
USB power → Visualizer beside display
HiFi system
USB power → Visualizer on equipment rack
Fosi Audio P3 is a compact tube preamplifier and headphone amplifier with RCA and Bluetooth 5.1 source inputs.Replaceable 5654W tubes, aptX-family Bluetooth codecs, bass and treble controls and outputs for headphones, amplifiers and powered speakers make it a versatile analog control stage.Why it stands outTube preamplifier characterA true tube stage adds adjustable tube character between line-level sources and the rest of the audio system.Wireless and wired inputsBluetooth 5.1 with Qualcomm QCC3031 and RCA input support convenient source switching.Headphone and system outputsA 3.5mm headphone jack, RCA output and AUX output support personal listening and downstream components.Hands-on tone controlFront bass and treble controls help adapt sound to headphones, speakers and room conditions.Best for
Adding Bluetooth and tube character to a power amplifier
Desktop wired headphone listening
Active speaker systems needing volume and tone control
Users interested in replaceable tube tuning
Not ideal for
Driving passive speakers directly
Turntables without a phono preamp
Systems requiring USB, optical or coaxial digital inputs
EMiUZEK Buying Notes
P3 is a preamplifier/headphone amplifier, not a speaker power amplifier.
Its RCA input is line level; a standard turntable needs a phono preamp.
RCA and AUX are downstream outputs, while the front 3.5mm jack is for headphones.
Frequently asked questionsCan P3 drive passive speakers?No. Connect it to a separate power amplifier or powered speakers.Can I use wired headphones?Yes. It supports 16–300Ω headphones through the front 3.5mm output.Does it accept digital inputs?Bluetooth is supported, but there is no USB, optical or coaxial input.Can I connect a turntable?Only through a built-in or external phono preamp before the RCA input.Can I connect an active subwoofer?The AUX or RCA line output can feed compatible downstream equipment; confirm the subwoofer's input and system gain arrangement.Are the tubes replaceable?Yes. The supplied 5654W tubes are replaceable with compatible tube types.HOW TO CONNECTPower amplifier systemSource: Streamer, DAC or Bluetooth deviceConnection: RCA or BluetoothOutput: RCA outputTarget: Power amplifier → passive speakersNote: P3 controls source level; the power amplifier drives the speakers.Powered speaker systemSource: Phone, streamer or DACConnection: Bluetooth or RCAOutput: RCA or AUX outputTarget: Powered speakersNote: Begin with low volume on both devices.Headphone setupSource: Phone, streamer or DACConnection: Bluetooth or RCAOutput: 3.5mm headphone outputTarget: 16–300Ω wired headphonesNote: Use the front volume and tone controls.Technical SpecificationsAudio performance
Feature
Specification
Product type
Tube preamplifier / headphone amplifier
Headphone impedance
16–300Ω
Headphone output
250mW at 16Ω; 150mW at 32Ω; 32mW at 250Ω; 20mW at 300Ω
Frequency response
20Hz–20kHz (±1dB)
SNR
≥103dB
THD
≤0.02%
Dynamic range
104dB
Crosstalk
95dB
Connectivity and power
Feature
Specification
Inputs
Bluetooth 5.1, RCA
Outputs
RCA, AUX, 3.5mm headphone
Bluetooth chip
Qualcomm QCC3031
Bluetooth codecs
SBC, AAC, aptX, aptX HD, aptX LL
Bluetooth range
≥10m
Power input
DC 12V / 1.5A–3A
Recommended System Setup
Setup
Connection
Stereo preamp
Source → P3 → Power amplifier → Passive speakers
Active speakers
Source → P3 → Powered speakers
Headphones
Source → P3 → Wired headphones
Additional Product ContentFosi Audio product comparisonCompare Fosi Audio compact preamplifier and tube DAC options by the capabilities that determine how they fit into a system.
Feature
P3
P4
GR40
Product position
Tube preamp + headphone amp
Solid-state analog preamp
Tube DAC + headphone amp
Analog inputs
RCA
RCA × 3
None
Digital / wireless inputs
Bluetooth 5.1
None
Bluetooth, USB, optical, coaxial
Main outputs
RCA, AUX
RCA, pre-out
RCA
Headphone output
3.5mm
No
3.5mm
Speaker amplification
No
No
No
Tube stage
Yes, replaceable 5654W
No
Yes
Tone controls
Bass and treble
Bass and treble with bypass
Bass and treble
Remote control
No
Yes
No
SNR
≥103dB
≥110dB
≥103dB
Best use
Bluetooth tube preamp and headphones
Multiple analog source control
Digital sources with tube conversion
Fosi Audio P4 is a compact solid-state stereo preamplifier that brings three RCA sources under one volume and tone-control stage.Its motorized analog volume control, remote operation, three-level gain, tone bypass and separate pre-out make it a practical partner for power amplifiers and powered subwoofers.Why it stands outThree-source analog hubThree RCA inputs allow convenient switching among a DAC, streamer, CD player or other line-level source.Motorized analog volume controlThe remote-driven analog potentiometer provides smooth level adjustment without replacing the analog signal path with digital volume control.Flexible tone and gain adjustmentBass, treble, bypass and three gain levels help match different source levels and listening preferences.Low-noise preamplifier performanceHigh SNR and low THD+N support clean system control in a compact all-metal chassis.Best for
Systems with multiple line-level analog sources
Power amplifiers needing source selection and remote volume
Powered speaker systems
2.1 systems using the volume-controlled pre-out
Not ideal for
Driving passive speakers directly
Turntables without a built-in or external phono preamp
Users needing Bluetooth or digital audio inputs
EMiUZEK Buying Notes
P4 is a preamplifier and cannot directly power passive speakers.
All three inputs are line-level RCA; a standard turntable requires a phono preamp.
Pre-out is volume controlled and suitable for compatible powered subwoofers or powered speakers.
Frequently asked questionsCan P4 drive passive speakers?No. Connect its RCA output to a power amplifier that drives the passive speakers.Does P4 include Bluetooth?No. It is an analog RCA preamplifier.Can I connect a turntable?Only if the turntable has a built-in phono stage or you use an external phono preamp.What is pre-out for?It provides a volume-controlled line-level output for compatible powered speakers, a powered subwoofer or downstream equipment.Can tone controls be bypassed?Yes. The bypass function provides a more direct signal path when tone adjustment is not needed.What does the gain setting do?The three gain levels help match differing source output levels and system sensitivity.HOW TO CONNECTPower amplifier systemSource: DAC, streamer, CD player or phono preampConnection: RCA inputOutput: RCA outputTarget: Power amplifier → passive speakersNote: Select the source and use P4 for volume control.Powered speaker systemSource: Up to three line-level sourcesConnection: RCA inputOutput: Pre-out or RCA outputTarget: Powered speakersNote: Begin with conservative volume settings on both devices.2.1 systemSource: Line-level sourceConnection: RCA inputOutput: RCA output + pre-outTarget: Power amplifier and powered subwooferNote: Use pre-out for the powered subwoofer and confirm crossover settings.Technical SpecificationsAudio performance
Feature
Specification
Product type
2.0-channel solid-state preamplifier
SNR
≥110dB
Dynamic range
≥110dB
THD+N
≤0.003%
Crosstalk
≥105dB
Noise floor
≤9μV
Frequency response
20Hz–20kHz (±0.1dB)
Tone adjustment
±12dB
Connectivity and power
Feature
Specification
Inputs
RCA × 3
Outputs
RCA, pre-out
Gain adjustment
+3dB / +6dB / +9dB
Volume control
Motorized analog potentiometer with remote
Power supply
DC 12V / 1.5A
Recommended System Setup
Setup
Connection
Stereo separates
Sources → P4 → Power amplifier → Passive speakers
Powered speakers
Sources → P4 → Powered speakers
2.1 separates
Sources → P4 → Power amplifier + powered subwoofer
Additional Product ContentFosi Audio product comparisonCompare the main Fosi Audio preamplifier choices by source support, outputs and the features that most affect system design.
Feature
P4
P3
ZP3
Product position
Compact analog preamp
Tube preamp + headphone amp
Balanced high-performance preamp
Analog inputs
RCA × 3
RCA
RCA × 2, XLR
Wireless / digital inputs
None
Bluetooth 5.1
None
Main outputs
RCA, pre-out
RCA, AUX
RCA, XLR, sub-out
Headphone output
No
3.5mm
No
Speaker amplification
No
No
No
Tube stage
No
Yes, replaceable 5654W
No
Tone controls
Bass and treble with bypass
Bass and treble
Bass and treble
Remote control
Yes
No
Yes
THD+N
≤0.003%
≤0.02%
≤0.0007%
SNR
≥110dB
≥103dB
≥115dB
Best use
Three analog sources and powered sub expansion
Bluetooth tube preamp and headphones
Balanced stereo system integration
Fosi Audio PH05 is a one-input, five-output headphone distribution amplifier for sharing one stereo source with up to five listeners.Five independently adjustable 310mW channels, master volume and one-touch mute make it useful for group listening, teaching, podcasting and headphone comparison.Why it stands outFive independent headphone channelsEach 3.5mm output has its own level control for different listeners and headphone sensitivities.310mW per channelAll five outputs provide rated power of 310mW at 32Ω for 16–300Ω headphones.Master control and instant muteA large master volume knob and one-touch mute simplify group control.Low-noise distribution designNE5532 amplification, 105dB SNR and 0.001% THD preserve a clean shared signal.Best for
Group listening sessions
Studio or podcast headphone monitoring
Teaching and language labs
Comparing several headphones from one source
Not ideal for
Combining several sources into one output
Headsets requiring microphone pass-through
Passive speakers or speaker-level amplification
EMiUZEK Buying Notes
PH05 is one input to five outputs; it cannot work in reverse as a five-input mixer.
All outputs are stereo 3.5mm headphone connections and do not carry microphone signals.
Set master and channel volumes low before connecting headphones.
Frequently asked questionsCan it accept five sources?No. PH05 distributes one stereo input to five headphone outputs.Can each listener set a different volume?Yes. Each output has an independent level control.Does it support headset microphones?No. It carries stereo playback audio only.Can it drive passive speakers?No. It is a headphone amplifier, not a speaker power amplifier.What headphones are supported?Fosi specifies 16–300Ω headphones.Can all five outputs be muted together?Yes. Use the one-touch mute function.HOW TO CONNECTGroup listeningSource: Phone, DAC, mixer or audio interfaceConnection: 3.5mm AUXOutput: Five 3.5mm outputsTarget: Up to five headphonesNote: Start with all channel levels low.Studio monitoringSource: Mixer or audio interfaceConnection: 3.5mm stereo lineOutput: Five headphone outputsTarget: Performers or reviewersNote: Use independent controls for each listener.Headphone comparisonSource: Single DAC or playerConnection: 3.5mm AUXOutput: Selected headphone outputsTarget: Multiple headphonesNote: Level-match carefully before comparing.Technical SpecificationsAudio performance
Feature
Specification
Rated output
310mW × 5 at 32Ω
Headphone impedance
16–300Ω
SNR / Dynamic range
105dB / 105dB
THD
0.001%
SINAD / Crosstalk
90dB / 90dB
Frequency response
20Hz–20kHz (±0.5dB)
Connections and power
Feature
Specification
Input
3.5mm AUX × 1
Outputs
3.5mm headphone × 5
Op-amp
TI NE5532
Power
DC 12V / 1A
Recommended System Setup
Setup
Connection
Group session
Source → PH05 → Up to five headphones
Studio
Audio interface → PH05 → Performers' headphones
Comparison
DAC → PH05 → Multiple headphones
Additional Product ContentFosi Audio product comparisonCompare the models by the differences that most affect system matching and everyday use.
Feature
PH05
PH04
Product position
Five-channel headphone distributor
Four-channel headphone distributor
Inputs
1 × 3.5mm stereo
1 × 3.5mm stereo
Headphone outputs
5 × 3.5mm
4 × 3.5mm
Independent volume
Five channels
Four channels
Output power
310mW per channel at 32Ω
40mW at 100Ω
Supported impedance
16–300Ω
Application dependent
Master volume
Yes
Yes
One-touch mute
Yes
No
Microphone support
No
No
Best use
Five-listener monitoring
Basic four-listener distribution
Fosi Audio Q4 is a compact desktop DAC and headphone amplifier that converts USB, optical or coaxial digital audio to headphones and RCA analog output.Volume plus bass and treble controls, 24-bit/192kHz S/PDIF decoding and support for 16–200Ω headphones make it a practical entry-level computer or TV audio upgrade.Why it stands outThree digital inputsUSB, optical and coaxial connections support computers, TVs, consoles and digital transports.Headphone and RCA outputsListen through 3.5mm headphones or feed an amplifier and powered speakers through RCA.Direct tone adjustmentFront bass and treble controls allow quick system tuning.Compact plug-and-play controlInput selection and analog volume are integrated into a small desktop chassis.Best for
Entry-level computer audio
TV optical PCM to headphones or stereo system
Desktop headphones and powered speakers
Users wanting physical bass and treble controls
Not ideal for
Dolby or DTS bitstream decoding
Balanced headphone systems
Headphones above the specified 200Ω range
EMiUZEK Buying Notes
Set TVs and consoles to two-channel PCM; Q4 does not decode Dolby or DTS.
Inserting headphones can mute the RCA output.
USB audio reaches 24-bit/96kHz; optical and coaxial reach 24-bit/192kHz.
Frequently asked questionsCan Q4 connect to a TV?Yes, through optical or coaxial when the TV is set to PCM stereo.Does it decode Dolby or DTS?No. Use PCM output to avoid noise or silence.Can it drive passive speakers?No. RCA must feed an amplifier, or use powered speakers.Can I use headphones and RCA together?The headphone connection can mute RCA output, so treat them as alternate outputs.Does USB need a driver?It is generally plug-and-play on listed systems; select Fosi Audio Q4 as the playback device.Can I connect an analog source?No. All Q4 inputs are digital.HOW TO CONNECTComputer headphonesSource: PC or MacConnection: USB audioOutput: 3.5mm headphoneTarget: 16–200Ω headphonesNote: Select Q4 as the playback device.TV headphonesSource: TelevisionConnection: Optical PCMOutput: 3.5mm headphoneTarget: Wired headphonesNote: Disable Dolby and DTS output.Stereo systemSource: Computer, TV or transportConnection: USB, optical or coaxialOutput: RCATarget: Amplifier or powered speakersNote: Use Q4 volume and tone controls.Technical SpecificationsAudio performance
Feature
Specification
USB sampling
Up to 24-bit / 96kHz
Optical / coaxial
Up to 24-bit / 192kHz
Headphone output
100mW at 32Ω
Headphone impedance
16–200Ω
THD / SNR
≤0.01% / ≥105dB
RCA output level
2.3V
Connections and physical
Feature
Specification
Inputs
USB, optical, coaxial
Outputs
3.5mm headphone, RCA
Chipset
SA9023 + CS8412 + 97220 + NE5532
Power
5V
Dimensions
73.5 × 98 × 33mm
Weight
251g
Recommended System Setup
Setup
Connection
Computer headphones
Computer → USB → Q4 → Headphones
TV system
TV optical PCM → Q4 → Amplifier
Powered speakers
Digital source → Q4 RCA → Powered speakers
Additional Product ContentFosi Audio product comparisonCompare the models by the differences that most affect system matching and everyday use.
Feature
Q4
K5 Pro
SK02
Product position
Entry desktop DAC/amp
Gaming DAC/amp
Higher-performance desktop DAC/amp
USB maximum
24-bit / 96kHz
24-bit / 96kHz
32-bit / 384kHz, DSD256
Other digital inputs
Optical, coaxial
Optical, coaxial
Optical
Headphone outputs
3.5mm
3.5mm
3.5mm, 4.4mm
Maximum headphone power
100mW at 32Ω
500mW at 32Ω
755mW at 32Ω via 4.4mm
Microphone input
No
Yes
No
RCA output
Yes
Yes
No
Tone controls
Bass, treble
Bass, treble
No
Balanced output
No
No
4.4mm
Best use
Simple PC/TV audio
Gaming with microphone
Hi-res desktop headphones
Fosi Audio Q6 is a compact fixed-output desktop DAC for converting USB-C, optical or coaxial digital sources to RCA analog audio and sub-out.Its AK4493S and XMOS XU316 chipset supports PCM 32-bit/768kHz and DSD512 over USB while delivering 121dB SNR for a clean stereo system upgrade.Why it stands outAKM desktop conversionThe AK4493S DAC and premium supporting chipset target high-resolution, low-distortion stereo playback.High-resolution USB audioUSB supports PCM up to 32-bit/768kHz and native DSD512.Three digital source inputsUSB-C, optical and coaxial connect computers, TVs, streamers and CD transports.RCA plus sub-outAnalog RCA and sub-out simplify stereo or 2.1 integration.Best for
Digital streamers and CD transports
Computer-based HiFi systems
TV optical PCM into an amplifier
Fixed-output DAC systems with downstream volume control
Not ideal for
Headphone listening without a separate headphone amplifier
Users needing built-in volume control or preamplification
Analog sources such as turntables
EMiUZEK Buying Notes
Q6 is a fixed-output DAC, not a preamplifier; control volume downstream.
It has no headphone output and requires an amplifier, headphone amp or powered speakers.
The sub-out is line level and requires a powered subwoofer.
Frequently asked questionsCan Q6 drive headphones?No. Add a separate headphone amplifier.Does it control volume?No. It is a fixed-output DAC, so use an amplifier, preamp or powered-speaker volume control.Can it connect to a turntable?No. It accepts digital inputs only.Can it connect to a TV?Yes, by optical or coaxial PCM audio.What does sub-out connect to?A powered subwoofer with a compatible line input.Does USB support DSD?Yes, up to DSD512 from a compatible source and playback setup.HOW TO CONNECTStreamer systemSource: Digital streamerConnection: Optical or coaxialOutput: RCATarget: Integrated amplifierNote: Control volume at the amplifier.Computer HiFiSource: PC, Mac or tabletConnection: USB-C audioOutput: RCATarget: Amplifier or powered speakersNote: Use compatible USB playback settings.2.1 systemSource: Digital sourceConnection: USB, optical or coaxialOutput: RCA + sub-outTarget: Amplifier + powered subwooferNote: Q6 output is fixed; manage levels downstream.Technical SpecificationsAudio performance
Feature
Specification
DAC / USB chipset
AK4493S / XMOS XU316
USB maximum
PCM 32-bit / 768kHz; DSD512
Optical / coaxial
Up to 32-bit / 192kHz
SNR / Dynamic range
≥121dB / 121dB
THD
<0.00012%
Connections and power
Feature
Specification
Inputs
USB-C, optical, coaxial
Outputs
RCA, sub-out
Other components
OPA1612, NE5532DR
Power supply
5V / 2A
Volume control
No; fixed output
Recommended System Setup
Setup
Connection
Streamer system
Streamer → Q6 → Integrated amplifier
Computer system
Computer → Q6 → Powered speakers
2.1 system
Digital source → Q6 → Amplifier + powered subwoofer
Additional Product ContentFosi Audio product comparisonCompare the models by the differences that most affect system matching and everyday use.
Feature
Q6
Q4
ZD3
Product position
Fixed-output stereo DAC
DAC + headphone amp / volume control
Balanced DAC / preamp
DAC chip
AK4493S
97220-based chipset
ES9039Q2M
USB maximum
32-bit / 768kHz, DSD512
24-bit / 96kHz
32-bit / 768kHz, DSD512
Other inputs
Optical, coaxial
Optical, coaxial
HDMI ARC, optical, coaxial, Bluetooth
Analog outputs
RCA, sub-out
RCA
RCA, XLR
Headphone output
No
3.5mm
No
Volume control
No
Yes
Yes with bypass
Balanced output
No
No
Yes, XLR
SNR
≥121dB
≥105dB
≥126dB
Best use
Simple high-performance DAC
Entry headphones and desktop
Flexible balanced TV/HiFi hub
Fosi Audio SK01 is a battery-powered analog headphone amplifier and preamplifier with 3.5mm line input, dual headphone jacks and adjustable three-band tone control.Up to 2400mW at 32Ω in high gain, pure bypass, loudness and a 2500mAh battery make it flexible for desktop and transportable wired listening.Why it stands outHigh-power analog headphone driveHigh gain delivers up to 2400mW at 32Ω for a broad 16–300Ω headphone range.Three-band tone shapingSeparate treble, midrange and bass controls allow more precise adjustment than basic two-band designs.Pure and loudness modesBypass removes tone processing, while loudness improves perceived bass and treble at low listening levels.Headphone amp and preamp3.5mm line out feeds an amplifier or powered speakers with the same volume and tone control.Best for
Powerful wired headphone listening
Analog sources needing portable amplification
Users wanting three-band tone control
Preamp use with powered speakers or a power amplifier
Not ideal for
USB digital audio or DAC conversion
Bluetooth wireless playback
Balanced headphone connections
EMiUZEK Buying Notes
SK01 is analog only; USB-C is for charging and does not carry audio data.
It cannot drive passive speakers directly; line out must feed an amplifier.
High gain can become very loud—start at minimum volume before wearing headphones.
Frequently asked questionsDoes USB-C carry audio?No. USB-C is for 5V charging only.Can it work as a preamp?Yes. Use 3.5mm line out into an amplifier or powered speakers.Can it drive passive speakers?No. A separate power amplifier is required.What headphones are supported?Fosi specifies 16–300Ω.Can tone controls be bypassed?Yes. PURE mode bypasses the tone circuit.How long does the battery last?Fosi states up to about six hours, depending on use and load.HOW TO CONNECTPortable headphonesSource: Phone, DAP or dongle DACConnection: 3.5mm line inOutput: 3.5mm or 6.35mm headphoneTarget: Wired headphonesNote: USB-C is not an audio input.Desktop preampSource: DAC or streamerConnection: 3.5mm line inOutput: 3.5mm line outTarget: Power amplifier or powered speakersNote: SK01 controls level and tone.High-impedance headphonesSource: Line-level DACConnection: 3.5mm line inOutput: 6.35mm headphoneTarget: 16–300Ω headphonesNote: Choose gain carefully and start low.Technical SpecificationsAudio performance
Feature
Specification
High / low gain output
2400mW / 300mW at 32Ω
Headphone impedance
16–300Ω
SNR
108dB
THD
≤0.001% at 1kHz / 770mV
Frequency response
20Hz–20kHz (±0.05dB)
Noise floor / Crosstalk
20μV / 83dB
Connections and power
Feature
Specification
Input
3.5mm line in
Outputs
3.5mm line out; 3.5mm and 6.35mm headphones
Tone adjustment
Treble ±8dB; mid ±10dB; bass ±11dB
Battery
2500mAh
Charging
DC 5V USB-C; power only
Recommended System Setup
Setup
Connection
Portable
Phone/DAP → SK01 → Headphones
Desktop
DAC → SK01 → Headphones
Preamp
Source → SK01 line out → Power amplifier
Additional Product ContentFosi Audio product comparisonCompare the models by the differences that most affect system matching and everyday use.
Feature
SK01
SK02
P3
Product position
Analog headphone amp / preamp
USB/optical DAC headphone amp
Tube preamp / headphone amp
Digital DAC
No
Yes, ES9038Q2M
Bluetooth input only
Main inputs
3.5mm line
USB, optical
Bluetooth, RCA
Headphone outputs
3.5mm, 6.35mm
3.5mm, 4.4mm
3.5mm
Maximum output at 32Ω
2400mW high gain
755mW via 4.4mm
150mW
Balanced headphone output
No
4.4mm
No
Tone controls
Treble, mid, bass
No
Bass, treble
Battery operation
Yes
No
No
Line / pre-out
3.5mm
3.5mm line / optical
RCA, AUX
Best use
Powerful analog portable amp
Hi-res desktop DAC/amp
Tube Bluetooth preamp
Fosi Audio SK02 is a compact desktop USB and optical DAC/headphone amplifier with 3.5mm and 4.4mm headphone outputs.An ES9038Q2M DAC, PCM 32-bit/384kHz and DSD256 decoding plus up to 755mW at 32Ω provide a capable all-in-one source for wired headphones and line-output systems.Why it stands outHi-res desktop DACES9038Q2M conversion supports PCM 384kHz and DSD256 over USB.Dual headphone outputs3.5mm single-ended and 4.4mm outputs support a wider range of headphone cables.Strong 4.4mm driveUp to 755mW at 32Ω provides useful power for many full-size headphones.DAC, headphone amp and pre-outThe 3.5mm line output can feed powered speakers or an external amplifier.Best for
Desktop wired headphone systems
PC and Mac high-resolution audio
Users with 4.4mm headphone cables
DAC/preamp use with powered speakers or an amplifier
Not ideal for
Analog source input
Bluetooth wireless playback
Microphone or gaming-chat input
EMiUZEK Buying Notes
SK02 accepts USB and optical digital inputs only; it has no analog input.
The 4.4mm connection is for headphones; verify cable termination before use.
Its 3.5mm output can operate as line out, while optical can also be passed out for a downstream DAC.
Frequently asked questionsCan I connect an analog source?No. Inputs are USB and optical digital audio.Does it support balanced headphones?It provides a 4.4mm headphone output; use a correctly terminated compatible cable.Can it feed powered speakers?Yes. Use the 3.5mm line output.Can it drive passive speakers?No. Add a power amplifier.What is the USB maximum?PCM 32-bit/384kHz and DSD256 from compatible software and sources.Can it output optical audio?Yes. The shared optical connection supports optical output for compatible downstream equipment.HOW TO CONNECTComputer headphonesSource: PC or MacConnection: USB-C audioOutput: 3.5mm or 4.4mm headphoneTarget: 16–300Ω headphonesNote: Select the correct gain and output mode.TV headphonesSource: TV or consoleConnection: Optical PCMOutput: Headphone outputTarget: Wired headphonesNote: Set the source to PCM stereo.Powered speakersSource: Computer or optical sourceConnection: USB or opticalOutput: 3.5mm line outTarget: Powered speakers or amplifierNote: Use line-out mode and manage system volume safely.Technical SpecificationsAudio performance
Feature
Specification
DAC chip
ESS ES9038Q2M
USB maximum
PCM 32-bit / 384kHz; DSD256
Optical maximum
24-bit / 192kHz
Headphone impedance
16–300Ω
3.5mm output
190mW at 32Ω
4.4mm output
755mW at 32Ω
THD
≤0.001% at 1kHz
Connections and physical
Feature
Specification
Inputs
USB, optical
Outputs
3.5mm headphone, 4.4mm headphone, 3.5mm line out / optical out
Frequency response
20Hz–20kHz (±0.02dB)
Power
5V USB-C
Dimensions
121 × 51 × 43mm
Weight
380g
Recommended System Setup
Setup
Connection
Computer headphones
Computer → USB → SK02 → Headphones
TV headphones
TV optical PCM → SK02 → Headphones
Powered speakers
Digital source → SK02 line out → Powered speakers
Additional Product ContentFosi Audio product comparisonCompare the models by the differences that most affect system matching and everyday use.
Feature
SK02
SK01
Q4
Product position
Hi-res desktop DAC/amp
Analog headphone amp/preamp
Entry DAC/amp with tone controls
DAC chip
ES9038Q2M
No DAC
97220-based chipset
Main inputs
USB, optical
3.5mm analog
USB, optical, coaxial
USB maximum
32-bit / 384kHz, DSD256
No USB audio
24-bit / 96kHz
Headphone outputs
3.5mm, 4.4mm
3.5mm, 6.35mm
3.5mm
Maximum output at 32Ω
755mW via 4.4mm
2400mW high gain
100mW
Analog line output
3.5mm
3.5mm
RCA
Tone controls
No
Three-band
Bass and treble
Battery operation
No
Yes
No
Best use
Hi-res desktop headphones
Powerful analog amplification
Simple PC/TV audio
Fosi Audio SP601 is a pair of 6.5-inch passive bookshelf speakers designed for stereo music and home entertainment systems.A silk-dome tweeter, HybridCone composite woofer and 80W RMS power handling provide a balanced upgrade for compact HiFi installations.
Why it stands outFour reasons this product deserves a place in a well-planned audio system.Two-Way Driver DesignA 1.5-inch silk-dome tweeter and 6.5-inch composite woofer divide high and low frequencies for clearer stereo reproduction.80W RMS Power HandlingThe pair is rated for 80W RMS and 160W peak power, supporting capable integrated amplifiers without requiring oversized cabinets.Flexible Speaker PlacementFront-facing drivers and tuned bass-reflex construction suit stands, shelves and media-room layouts.Standard Passive IntegrationDual-mode binding posts support common speaker-cable terminations and make the SP601 easy to integrate with a stereo amplifier.
Best for
Compact stereo music systems
Bookshelf or speaker-stand installations
TV and home entertainment systems with an external amplifier
Listeners upgrading from small entry-level passive speakers
Not ideal for
Users who need powered speakers with built-in amplification
Wireless-only systems without a speaker amplifier
Very large rooms requiring high-output floorstanding speakers
EMiUZEK Buying Notes
SP601 is a passive speaker pair and must be connected to a compatible stereo amplifier.
Match the amplifier and listening level to the speakers' 4Ω nominal impedance and 80W RMS rating.
Speaker cable is required between the amplifier and each speaker.
Frequently Asked QuestionsDo the SP601 speakers include an amplifier?No. They are passive speakers and require an external power or integrated amplifier.What amplifier impedance support is required?Use an amplifier rated to operate safely with 4Ω speakers.Can they connect directly to a television?Only if the television feeds a compatible external amplifier; the speakers cannot accept a TV signal directly.Can I use banana plugs?The dual-mode binding posts are designed for common speaker-cable terminations, including compatible banana plugs.Are they sold as a pair?Yes, the SP601 is supplied as a stereo speaker pair.Do they support Bluetooth or Wi-Fi?Not by themselves. Add a Bluetooth receiver or network streamer through the amplifier if wireless playback is required.
HOW TO CONNECTStereo HiFi systemSource: DAC, streamer or CD playerConnection: RCA / digital connection to amplifierOutput: Speaker cableTarget: Stereo amplifier → SP601 pairNote: Observe left/right speaker polarity.TV audio systemSource: TelevisionConnection: HDMI ARC / optical to compatible amplifierOutput: Speaker cableTarget: Amplifier → SP601 pairNote: The amplifier must decode the TV audio signal.Desktop systemSource: Computer / USB DACConnection: Line-level audio to amplifierOutput: Speaker cableTarget: Compact amplifier → SP601 pairNote: Place both speakers at similar height and distance.
Technical SpecificationsSpeaker
Feature
Specification
Product Type
Two-way passive bookshelf speaker
Tweeter
1.5-inch silk dome
Woofer
6.5-inch HybridCone composite
Nominal Impedance
4Ω
Sensitivity
86dB
Power
Feature
Specification
RMS Power Handling
80W
Peak Power Handling
160W
Amplification
External amplifier required
Connections
Feature
Specification
Speaker Terminals
Dual-mode binding posts
Wireless Connectivity
None
Recommended System Setup
Setup
Connection
Stereo music
Source → amplifier → SP601 pair
TV system
TV → AV/stereo amplifier → SP601 pair
Desktop HiFi
Computer/DAC → compact amplifier → SP601 pair
Additional Product ContentNo like-for-like comparison is included because this model has a distinct product role.
Fosi Audio T20 is a compact Bluetooth tube integrated amplifier for passive speakers and wired headphones.
It combines 50W x2 Class D speaker power with replaceable vacuum tubes, RCA input and tone controls for a warm, flexible desktop stereo system.
Why it stands out
Four reasons this product deserves a place in a well-planned audio system.
Tube-Buffered Sound
Replaceable vacuum tubes add the tube stage and allow compatible tube rolling.
Speaker and Headphone Listening
The T20 powers passive speakers and also provides a front 3.5mm headphone output.
Bluetooth and RCA Inputs
Switch between convenient wireless playback and a conventional analog source.
Compact Tone Control
Independent bass and treble controls make it easier to adapt the system to speakers, headphones and room acoustics.
Best for
Desktop passive-speaker systems
Bluetooth music playback
Headphone and speaker listening from one compact amplifier
Listeners interested in compatible tube rolling
Not ideal for
Users requiring optical, USB or HDMI inputs
Balanced XLR audio systems
Turntables without a built-in or external phono preamp
Users needing a dedicated subwoofer output
EMiUZEK Buying Notes
T20 is an integrated speaker amplifier and can directly drive compatible 4–8Ω passive speakers.
Its RCA input is line level; a conventional turntable requires a separate phono preamplifier.
The 3.5mm jack is a headphone output, not a microphone connection.
Frequently Asked Questions
Can the T20 drive passive speakers directly?
Yes. Connect a compatible 4–8Ω passive speaker pair to the rear speaker terminals.
Can I connect a turntable?
Yes only when the turntable has a built-in phono preamp or is used with an external phono preamp.
Does it work as a headphone amplifier?
Yes, it includes a front 3.5mm headphone output.
Does it accept digital audio?
No. Inputs are Bluetooth and analog RCA; optical and USB audio are not provided.
Can the tubes be replaced?
Yes. Use only compatible tube types and power the unit off before replacement.
Does it have a subwoofer output?
No dedicated subwoofer output is specified. Use a subwoofer integration method supported by your wider system.
HOW TO CONNECT
Bluetooth speaker system
Source: Phone / tabletConnection: BluetoothOutput: Speaker terminalsTarget: Passive speakersNote: Pair the source and set volume low before playback.
Wired stereo system
Source: DAC / streamer / CD playerConnection: RCA line inputOutput: Speaker terminalsTarget: Passive speakersNote: Use a fixed or controlled line-level source.
Headphone listening
Source: Phone via Bluetooth or RCA sourceConnection: Bluetooth / RCAOutput: 3.5mm headphone outputTarget: Wired headphonesNote: Lower volume before inserting headphones.
Technical Specifications
Amplifier
Feature
Specification
Product Type
Bluetooth tube integrated amplifier
Amplifier Chip
TI TPA3116
Maximum Speaker Output
50W x2 at 4Ω
Speaker Impedance
4–8Ω
Connectivity
Feature
Specification
Inputs
Bluetooth 5.0; RCA line input
Outputs
Passive speaker terminals; 3.5mm headphone
Tone Controls
Bass and treble
Audio
Feature
Specification
Vacuum Tubes
Replaceable 6K4 pair
Frequency Response
20Hz–20kHz (±1.5dB)
THD
≤0.04%
SNR
≥99dB
Recommended System Setup
Setup
Connection
Wireless stereo
Phone → Bluetooth → T20 → passive speakers
Wired stereo
Streamer/DAC → RCA → T20 → passive speakers
Headphones
Source → T20 → 3.5mm headphones
Additional Product Content
Feature
T20
T20X
P3
Product Position
50W x2 tube integrated amp
100W x2 tube integrated amp
Tube preamp / headphone amp
Passive Speaker Amplifier
Yes
Yes
No
Inputs
Bluetooth 5.0, RCA
Bluetooth, AUX
Bluetooth, RCA
Speaker Output
50W x2 max at 4Ω
100W x2 max at 4Ω
None
Headphone Output
3.5mm
3.5mm
3.5mm
Tone Controls
Bass, treble
Bass, treble
Bass, treble
Tube Rolling
Compatible tubes
Compatible tubes
Compatible tubes
Best Use
Compact speaker/headphone system
Higher-power speaker system
Add tube preamp/headphone stage
Fosi Audio T20X is a Bluetooth vacuum-tube integrated amplifier for passive speakers and wired headphones.Its upgraded 100W x2 output, replaceable tubes and bass/treble controls create a compact all-in-one amplifier for desktop and bookshelf systems.
Why it stands outFour reasons this product deserves a place in a well-planned audio system.100W x2 Maximum OutputThe Class D power stage provides more headroom than the T20 for compatible passive speakers.Replaceable Tube StageTube rolling lets experienced users experiment with compatible tube options.Two Listening OutputsDrive passive speakers or use the 3.5mm headphone connection from the same amplifier.Simple Wireless and Analog PlaybackBluetooth and analog input cover the most common phone, streamer and DAC setups without a complex interface.
Best for
Bookshelf passive-speaker systems
Bluetooth desktop audio
Combined speaker and headphone listening
Listeners wanting tube character with higher output than the T20
Not ideal for
Users requiring optical, USB or HDMI audio
Balanced XLR systems
Turntables without phono amplification
Systems needing a dedicated subwoofer output
EMiUZEK Buying Notes
T20X is an integrated amplifier and can directly drive compatible 2–8Ω passive speakers.
Its analog input is line level; use a phono preamp with a conventional turntable.
The maximum output figure depends on speaker impedance, supply voltage and test conditions.
Frequently Asked QuestionsCan the T20X drive passive speakers?Yes. It is an integrated amplifier with passive-speaker outputs.Can it connect to a turntable?Yes when the turntable has a built-in phono preamp or an external phono preamp is used.Does it include a headphone output?Yes, a 3.5mm wired headphone output is provided.Does it support optical or USB audio?No. Use Bluetooth or the analog input.Can the vacuum tubes be replaced?Yes. Use compatible tubes and switch the amplifier off before tube replacement.Can I connect an active subwoofer?No dedicated subwoofer output is specified; use a compatible system-level integration method.
HOW TO CONNECTBluetooth stereoSource: Phone / tabletConnection: BluetoothOutput: Speaker terminalsTarget: Passive speakersNote: Keep initial volume low when pairing.Wired HiFiSource: Streamer / DAC / CD playerConnection: Analog line inputOutput: Speaker terminalsTarget: Passive speakersNote: Use a line-level source.Headphone systemSource: Bluetooth or analog sourceConnection: Bluetooth / line inputOutput: 3.5mm headphone outputTarget: Wired headphonesNote: Disconnect or lower speaker listening as appropriate.
Technical SpecificationsAmplifier
Feature
Specification
Product Type
Bluetooth tube integrated amplifier
Amplifier Chip
TI TPA3221
Maximum Output
100W x2 at 4Ω
Speaker Impedance
2–8Ω
Audio
Feature
Specification
Frequency Response
20Hz–20kHz (±1dB)
THD
≤0.3%
SNR
≥86dB
Input Sensitivity
≤650mV
Connectivity and Power
Feature
Specification
Inputs
Bluetooth; analog line input
Outputs
Passive speaker terminals; 3.5mm headphone
Power Supply
24V/4.5A included
DC Input Range
12–30V
Recommended System Setup
Setup
Connection
Wireless speaker system
Phone → Bluetooth → T20X → passive speakers
Wired stereo
Streamer/DAC → line input → T20X → passive speakers
Headphones
Source → T20X → 3.5mm headphones
Additional Product Content
Feature
T20X
T20
P3
Product Position
Higher-power tube integrated amp
Compact tube integrated amp
Tube preamp / headphone amp
Passive Speaker Amplifier
Yes
Yes
No
Maximum Speaker Output
100W x2 at 4Ω
50W x2 at 4Ω
Not applicable
Inputs
Bluetooth, line input
Bluetooth 5.0, RCA
Bluetooth, RCA
Headphone Output
3.5mm
3.5mm
3.5mm
Tone Controls
Bass, treble
Bass, treble
Bass, treble
Tube Rolling
Compatible tubes
Compatible tubes
Compatible tubes
Best Use
More speaker headroom
Compact speaker system
Existing amplifier / active speakers
Fosi Audio TB10D is a compact analog stereo power amplifier for driving passive speakers from a line-level source.Its TI TPA3255 power stage, 300W x2 maximum rating and front bass/treble controls deliver strong value for simple, adjustable HiFi systems.
Why it stands outFour reasons this product deserves a place in a well-planned audio system.TPA3255 AmplificationTexas Instruments Class D architecture provides high efficiency and substantial power from a compact chassis.300W x2 Maximum RatingThe amplifier offers useful headroom for compatible 2–8Ω passive speakers; real output depends on the supply and speaker load.Front Tone ControlsDedicated bass and treble knobs allow quick adjustment without an app or external equalizer.Straightforward Analog SystemOne RCA input and speaker outputs keep setup simple for users who already own a DAC, streamer or preamp.
Best for
Budget-focused passive-speaker systems
Users who want physical bass and treble adjustment
Desktop and small-room stereo systems
Pairing with an existing DAC, streamer or preamp
Not ideal for
Users requiring Bluetooth, USB, optical or HDMI inputs
Balanced XLR systems
Headphone listening
Systems requiring a dedicated subwoofer or preamplifier output
EMiUZEK Buying Notes
TB10D is an analog speaker amplifier; it requires a separate line-level source.
The 300W x2 figure is a maximum rating under specific conditions, not continuous output with every power supply and speaker.
It has no headphone, Bluetooth or dedicated subwoofer output.
Frequently Asked QuestionsCan the TB10D drive passive speakers directly?Yes. It supports compatible 2–8Ω passive speakers.Does it include Bluetooth?No. Add a Bluetooth receiver or streamer to the RCA input if wireless playback is needed.Can I connect a turntable?Only through a turntable with built-in phono output or a separate phono preamplifier.Does it have a subwoofer output?No dedicated subwoofer or pre-out is provided.Can I use a DAC or network streamer?Yes. Connect its analog line output to the TB10D RCA input.What does 300W x2 mean?It is the specified maximum output under particular supply and load conditions; usable continuous power varies with the system.
HOW TO CONNECTDAC stereo systemSource: Computer / digital sourceConnection: USB or digital to DAC; RCA from DACOutput: Speaker terminalsTarget: Passive speakersNote: Set the DAC to line or controlled output as appropriate.Network streaming systemSource: Network streamerConnection: RCA line outputOutput: Speaker terminalsTarget: Passive speakersNote: Use the streamer for source selection and playback.TV stereo systemSource: TelevisionConnection: Optical/HDMI to external DAC; RCA to TB10DOutput: Speaker terminalsTarget: Passive speakersNote: TB10D does not accept TV digital audio directly.
Technical SpecificationsAmplifier
Feature
Specification
Product Type
Analog stereo Class D amplifier
Amplifier Chip
TI TPA3255
Maximum Output
300W x2 at 4Ω
Speaker Impedance
2–8Ω
Audio
Feature
Specification
Frequency Response
20Hz–40kHz (±2dB)
THD
≤0.3%
SNR
≥90dB
Input Sensitivity
≤600mV
Connectivity and Power
Feature
Specification
Input
Stereo RCA line input
Output
Passive speaker binding posts
Tone Controls
Bass and treble
DC Input
18–48V
Included Power Supply
32V/5A
Recommended System Setup
Setup
Connection
DAC system
Digital source → DAC → RCA → TB10D → passive speakers
Streamer system
Streamer → RCA → TB10D → passive speakers
TV system
TV → external DAC → RCA → TB10D → passive speakers
Additional Product Content
Feature
TB10D
V3 Stereo
BT20A Pro
Product Position
Tone-control stereo amp
Pure stereo amp
Bluetooth stereo amp
Amplifier Chip
TPA3255
TPA3255
TPA3255
Maximum Output
300W x2 at 4Ω
300W x2 at 4Ω
300W x2 at 4Ω
Analog Input
RCA
RCA
RCA
Bluetooth
No
No
Yes
Tone Controls
Bass, treble
No
Bass, treble
Pre-out
No
Yes
Yes
Speaker Load
2–8Ω
2–8Ω
2–8Ω
Best Use
Simple adjustable stereo
Minimal pure analog path
Wireless stereo system
This Fosi Audio V3 listing is for the V3 Mono compact monoblock power amplifier, sold in single-amp and stereo-pair configurations depending on the selected variant.Its TPA3255-based architecture, XLR balanced/RCA inputs and 240W rated mono output support scalable, high-power passive-speaker systems.
Why it stands outFour reasons this product deserves a place in a well-planned audio system.True Monoblock ArchitectureEach V3 Mono amplifies one audio channel, allowing separate left/right amplification in a stereo pair.XLR Balanced and RCA InputsThe selectable input formats make integration practical with balanced preamps, DACs and conventional RCA sources.240W Rated Mono OutputStrong single-channel output supports demanding compatible passive speakers when correctly powered.Scalable Power OptionsVariants include amplifier-only and power-supply bundles, including configurations for one or two monoblocks.
Best for
Stereo systems using two monoblock amplifiers
Balanced XLR preamp or DAC systems
Compact high-power passive-speaker installations
Users planning a modular amplifier upgrade
Not ideal for
Buyers expecting one unit to power both stereo channels
Users without a preamp, DAC or source with volume control
Headphone or powered-speaker systems
Buyers who have not checked whether their selected variant includes a power supply
EMiUZEK Buying Notes
This product is V3 Mono: one amplifier powers one speaker channel; two units are required for conventional stereo.
Check the selected variant carefully because amplifier quantity and included power supply differ.
Use a preamp, DAC or source with suitable volume control; V3 Mono is a power amplifier, not a complete source device.
Frequently Asked QuestionsDo I need one or two V3 Mono amplifiers?One unit powers one channel. A standard two-channel stereo system requires two monoblocks.Does every variant include a power supply?No. The listing includes amplifier-only and power-supply bundle options; verify the selected variant.Can it connect to an XLR source?Yes. It supports balanced XLR input as well as RCA input.Can it drive headphones?No. It is a passive-speaker power amplifier and has no headphone output.Does it include Bluetooth or a DAC?No. Connect a compatible external preamp, DAC or streamer.Can I use one 48V/10A supply with two units?A listed two-amplifier bundle is available with a 48V/10A supply; use only the configuration and cabling supplied or specified for that variant.
HOW TO CONNECTBalanced stereo systemSource: Balanced DAC / preampConnection: XLR to each monoblockOutput: Speaker terminalsTarget: One passive speaker per V3 MonoNote: Use two units for left and right channels.RCA stereo systemSource: RCA preamp / controlled DACConnection: RCA to each monoblockOutput: Speaker terminalsTarget: One passive speaker per V3 MonoNote: Split left and right outputs to separate units.Single-channel systemSource: Mono source / preamp channelConnection: XLR or RCAOutput: Speaker terminalsTarget: One passive speakerNote: One unit powers one channel only.
Technical SpecificationsAmplifier
Feature
Specification
Product Type
Mono Class D power amplifier
Amplifier Chip
TI TPA3255
Rated Output
240W mono
Channels per Unit
1
Connectivity
Feature
Specification
Inputs
XLR balanced; RCA
Output
Passive speaker binding posts
Input Selection
Balanced / RCA selectable
Headphone Output
None
Power and Design
Feature
Specification
Power Options
Variant-dependent: no PSU, 48V/5A or 48V/10A bundles
Cooling
Full-body heat-dissipation chassis
System Requirement
Preamp or source with volume control
Recommended System Setup
Setup
Connection
Balanced stereo
Balanced DAC/preamp → two V3 Mono amps → passive speaker pair
RCA stereo
RCA preamp → two V3 Mono amps → passive speaker pair
Single channel
Mono line source → one V3 Mono → one passive speaker
Additional Product Content
Feature
V3 Mono
ZA3
V3 Stereo
Amplifier Format
Monoblock
Stereo / mono-capable
Stereo
Channels per Unit
1
2 stereo or 1 mono
2
Amplifier Chip
TPA3255
TPA3255
TPA3255
Inputs
XLR balanced, RCA
XLR balanced, RCA
RCA
Rated / Maximum Positioning
240W rated mono
High-power stereo/mono
300W x2 maximum
Stereo Units Required
2
1 in stereo mode
1
Pre-out
No
Subwoofer output
3.5mm pre-out
Tone Controls
No
No
No
Best Use
Dedicated monoblock stereo
Flexible balanced amp
Simple RCA stereo
Fosi Audio ZA3 is a balanced Class D power amplifier that operates in stereo or high-power mono mode.Its TPA3255 platform, XLR/TRS and RCA inputs, active-subwoofer output and scalable architecture make it a flexible foundation for compact HiFi systems.Why it stands outFour reasons this product deserves a place in a well-planned audio system.Stereo or Mono OperationUse one ZA3 for a conventional stereo system or two units in mono mode for a scalable dual-mono installation.Balanced XLR/TRS InputThe combo balanced input helps reject interference and integrates with balanced DACs and preamplifiers.Active Subwoofer OutputA dedicated line-level output simplifies adding a powered subwoofer to a stereo system.Replaceable Op-AmpsSocketed op-amps let experienced users experiment with compatible DIP8 dual op-amps.Best for
Balanced DAC and preamp systems
Stereo passive-speaker systems
Dual-mono amplifier upgrades
2.1 systems using a powered subwoofer
Installations using 12V trigger control
Not ideal for
Users expecting Bluetooth, USB or digital inputs
Buyers needing a headphone output
Passive subwoofers without their own amplifier
Buyers who have not checked whether their variant includes a power adapter
EMiUZEK Buying Notes
ZA3 is a power amplifier and requires an external source or preamp with suitable volume control.
The subwoofer output is line level and is only for a powered subwoofer.
Check the selected variant: amplifier-only, 32V/5A and 48V/5A power options are listed separately.
Frequently Asked QuestionsCan one ZA3 power a stereo pair?Yes. Use stereo mode to power left and right passive speakers from one unit.When are two ZA3 amplifiers required?Use two units when building a dual-mono stereo system, with one amplifier assigned to each channel.Can it connect to an XLR source?Yes. The balanced combo input supports XLR and 1/4-inch TRS connections.Can it power a passive subwoofer?No. Its subwoofer output is line level and requires a powered subwoofer.Does it include Bluetooth or a DAC?No. Connect an external DAC, streamer or preamplifier through RCA or balanced input.Does every option include a power supply?No. Verify the selected product variant before ordering.HOW TO CONNECTBalanced stereo systemSource: Balanced DAC or preampConnection: XLR / 1/4-inch TRSOutput: Speaker terminalsTarget: Passive speaker pairNote: Set ZA3 to stereo mode.Dual-mono systemSource: Balanced DAC or preampConnection: One balanced channel to each ZA3Output: Speaker terminal in mono configurationTarget: One passive speaker per amplifierNote: Use two ZA3 units and set both to mono mode.2.1 stereo systemSource: DAC / preampConnection: RCA or balanced inputOutput: Speaker outputs plus sub-outTarget: Passive speakers and powered subwooferNote: Do not connect a passive subwoofer to sub-out.Technical SpecificationsAmplifier
Feature
Specification
Product Type
Stereo/mono Class D power amplifier
Amplifier Chip
Texas Instruments TPA3255
Speaker Impedance
2–8Ω
Modes
Stereo / PBTL mono
Performance
Feature
Specification
Rated Output with 48V/5A
155W x2 at 4Ω stereo; 235W x1 at 4Ω mono
Rated Output with 32V/5A
95W x2 at 4Ω stereo; 110W x1 at 4Ω mono
Frequency Response
20Hz–20kHz (±0.1dB)
SINAD
89dB
SNR
≥106dB
THD
<0.006%
Dynamic Range
≥106dB
Connectivity and Power
Feature
Specification
Inputs
RCA; XLR / 1/4-inch TRS balanced combo
Outputs
Passive speakers; active subwoofer line output
Trigger
12V trigger input
DC Input Range
24–48V
Power Options
32V/5A or 48V/5A; variant dependent
Recommended System Setup
Setup
Connection
Stereo HiFi
DAC/preamp → ZA3 stereo mode → passive speaker pair
Dual mono
Balanced preamp → two ZA3 units → passive speaker pair
2.1 system
Source/preamp → ZA3 → passive speakers + powered subwoofer
Additional Product Content
Feature
ZA3
V3 Mono
TB10D
Amplifier Format
Stereo / mono selectable
Monoblock
Stereo
Amplifier Chip
TPA3255
TPA3255
TPA3255
Inputs
XLR/TRS, RCA
XLR, RCA
RCA
Stereo from One Unit
Yes
No
Yes
Mono Mode
Yes
Always mono
No
Active Subwoofer Output
Yes
No
No
12V Trigger
Input
No
No
Tone Controls
No
No
Bass, treble
Op-Amp Rolling
Yes
Yes
No
Best Use
Flexible balanced stereo/mono
Dedicated monoblocks
Simple adjustable stereo
Fosi Audio ZD3 is a fully balanced desktop DAC and preamplifier for computers, televisions, wireless sources and dedicated digital transports.The ES9039Q2M platform, HDMI ARC, USB, Bluetooth, XLR/RCA outputs and bypass mode make it a versatile digital hub for modern HiFi systems.Why it stands outFour reasons this product deserves a place in a well-planned audio system.ES9039Q2M Balanced ConversionThe flagship ESS DAC architecture supports high-resolution decoding and balanced analog output.HDMI ARC for Television AudioConnect a compatible TV directly and control a stereo system without relying on a separate AV receiver.Variable or Fixed OutputUse preamp mode for direct volume control or bypass mode for a fixed-level connection to another preamplifier.Trigger and Remote Integration12V trigger input/output, OLED display and remote control streamline everyday system operation.Best for
TV-to-HiFi upgrades using HDMI ARC
Balanced power amplifiers such as ZA3 or V3 Mono
Computer USB audio systems
Bluetooth and multi-source digital systems
Active speakers with XLR or RCA input
Not ideal for
Users needing built-in speaker amplification
Headphone listeners without a separate headphone amplifier
Analog-only sources such as a turntable
Systems requiring Wi-Fi network streaming apps inside the DAC
EMiUZEK Buying Notes
ZD3 is a DAC/preamp, not a speaker power amplifier; connect it to active speakers or a separate amplifier.
Use bypass only when downstream equipment provides volume control, because bypass sends fixed-level output.
HDMI is ARC audio input rather than a general HDMI video switch or HDMI output.
Frequently Asked QuestionsCan the ZD3 drive passive speakers?No. Connect its XLR or RCA output to a power amplifier before passive speakers.Can it connect directly to a television?Yes, through a compatible HDMI ARC connection. Configure the television for supported digital audio output.Does it have a headphone output?No. Add a separate headphone amplifier if headphone listening is required.Can it connect to active speakers?Yes. Use XLR or RCA output and operate the ZD3 in preamp mode for volume control.What is bypass mode?It bypasses variable preamp control and sends fixed-level output to a downstream preamp or integrated amplifier.Does Bluetooth transmit to headphones?No. Bluetooth is an input for receiving audio from a source device.Does it support high-resolution USB audio?Yes, up to PCM 32-bit/768kHz and DSD512 over USB with compatible hardware and software.HOW TO CONNECTTV stereo systemSource: TelevisionConnection: HDMI ARCOutput: XLR or RCATarget: Power amplifier or active speakersNote: Select a compatible PCM output setting on the TV if required.Computer audioSource: PC / MacConnection: USBOutput: XLR or RCATarget: Power amplifier, headphone amp or active speakersNote: Some Windows configurations require the Fosi USB driver.Wireless audio systemSource: Phone / tabletConnection: Bluetooth 5.0Output: XLR or RCATarget: Amplifier or active speakersNote: Bluetooth is receive-only on the ZD3.Technical SpecificationsCore Architecture
Feature
Specification
Product Type
Balanced DAC / preamplifier
DAC
ESS ES9039Q2M
USB Interface
XMOS XU316
Bluetooth Chip
QCC3031
Op-Amp
LME49720; swappable design
Digital Audio
Feature
Specification
USB Maximum
PCM 32-bit/768kHz; DSD512
Optical / Coaxial Maximum
PCM 24-bit/192kHz
Bluetooth Maximum
PCM 24-bit/48kHz
Bluetooth Codecs
aptX HD, aptX, AAC, SBC
Bluetooth Version
5.0
Inputs and Outputs
Feature
Specification
Inputs
USB, HDMI ARC, coaxial, optical, Bluetooth
Outputs
Balanced XLR; RCA
XLR Output Level
5Vrms
RCA Output Level
2.5Vrms
Trigger
12V trigger input and output
Measured Performance
Feature
Specification
SINAD
126dB
SNR
≥126dB
THD+N
<0.00008%
Dynamic Range
≥123dB
Noise Floor
≤2μV
Power Supply
DC 12V/1.5A
Recommended System Setup
Setup
Connection
TV HiFi
TV → HDMI ARC → ZD3 → amplifier → passive speakers
Balanced desktop
Computer → USB → ZD3 → XLR active speakers
Wireless system
Phone → Bluetooth → ZD3 → amplifier or active speakers
Additional Product Content
Feature
ZD3
ZH3
GR40
Product Position
Balanced DAC / preamp
DAC / headphone amp / preamp
Tube DAC / headphone amp
DAC Chip
ES9039Q2M
AKM AK4493SEQ
Not specified
USB Maximum
PCM 768kHz / DSD512
PCM 768kHz / DSD512
Product-dependent lower tier
HDMI ARC
Yes
No
No
Bluetooth Input
Yes
No
Yes
Headphone Output
No
4.4mm, 6.35mm
3.5mm
Analog Input
No
RCA
No
Balanced Line Output
XLR
XLR
No
Remote Control
Yes
Yes
No
Best Use
TV and balanced amplifier hub
Complete desktop/headphone hub
Compact tube-flavoured desktop audio
Fosi Audio ZH3 is an all-in-one desktop DAC, balanced headphone amplifier and preamplifier for headphones, active speakers and external amplifiers.Its AK4493SEQ DAC, powerful 4.4mm balanced output, multiple digital/analog inputs and XLR/RCA pre-outs create a complete desktop HiFi control center.Why it stands outFour reasons this product deserves a place in a well-planned audio system.All-in-One Desktop HubDAC, headphone amplification and preamp functions reduce the need for several separate components.2570mW Balanced Headphone OutputThe 4.4mm output provides substantial power at 32Ω, while three gain levels support a broad range of headphones.High-Resolution AKM PlatformXMOS XU316 and AK4493SEQ support PCM 32-bit/768kHz and DSD512 playback.Flexible System ControlRCA/XLR line outputs, remote control, tone adjustment, six filters and swappable op-amps support system customization.Best for
Desktop headphone systems
Balanced 4.4mm headphone listening
Active studio monitors and powered speakers
External power amplifiers requiring preamp control
Computer and game-console USB audio
Not ideal for
Users needing built-in passive-speaker amplification
Wireless Bluetooth-only systems
TV systems requiring HDMI ARC
Portable or battery-powered listening
EMiUZEK Buying Notes
ZH3 can drive headphones and control active speakers or a power amplifier, but it cannot directly drive passive speakers.
Its USB input supports UAC 1.0 and 2.0 modes; choose the compatible mode for computers or game consoles.
RCA is an analog input, while RCA and XLR line outputs are intended for downstream active speakers or amplifiers.
Frequently Asked QuestionsCan the ZH3 drive passive speakers?No. Use its line outputs with a separate power amplifier, or connect active speakers.Which headphone outputs are included?It provides 4.4mm balanced and 6.35mm single-ended headphone outputs.Does it support Bluetooth?No Bluetooth input is specified. Use USB, optical, coaxial or analog RCA input.Can I connect a game console?Yes. UAC 1.0/2.0 switching supports compatible game-console USB audio configurations.Can it connect to active speakers?Yes. Use RCA or balanced XLR line output and control volume through the ZH3 preamp.Can it accept an analog source?Yes, through RCA analog input.What headphones can it support?The three-level gain system is specified for approximately 16–300Ω headphones; start with low gain and low volume.HOW TO CONNECTComputer headphone systemSource: PC / MacConnection: USBOutput: 4.4mm or 6.35mmTarget: Wired headphonesNote: Choose UAC mode and gain appropriate for the source and headphones.Active speaker systemSource: Computer / digital transport / analog sourceConnection: USB, optical, coaxial or RCAOutput: XLR or RCA line outputTarget: Active speakersNote: Use preamp volume control and begin at a low level.External amplifier systemSource: Digital or analog sourceConnection: USB, optical, coaxial or RCAOutput: XLR or RCA line outputTarget: Power amplifier → passive speakersNote: ZH3 supplies the DAC and preamp stages only.Technical SpecificationsCore Architecture
Feature
Specification
Product Type
DAC / balanced headphone amplifier / preamplifier
DAC
AKM AK4493SEQ
USB Interface
XMOS XU316
Headphone Amplifiers
OPA1612 x4
Maximum Resolution
PCM 32-bit/768kHz; DSD512
Inputs and Outputs
Feature
Specification
Inputs
USB, optical, coaxial, RCA analog
Headphone Outputs
4.4mm balanced; 6.35mm single-ended
Line Outputs
Balanced XLR; RCA
USB Modes
UAC 1.0 / UAC 2.0
Trigger
12V trigger connection
Headphone Performance
Feature
Specification
4.4mm Output at 32Ω
2570mW x2
6.35mm Output at 32Ω
640mW x2
Gain
Three levels
Headphone Impedance Range
16–300Ω
Audio Performance
Feature
Specification
SINAD
≥115dB
SNR
≥121dB
THD+N
≤0.00018%
Noise Floor
≤1.9μV
Sound Adjustment
Bass/treble EQ; six filters; bypass
Power Supply
DC 12V
Recommended System Setup
Setup
Connection
Headphones
Computer → USB → ZH3 → 4.4mm/6.35mm headphones
Active speakers
Source → ZH3 → XLR/RCA active speakers
Passive speakers
Source → ZH3 → power amplifier → passive speakers
Additional Product Content
Feature
ZH3
ZD3
GR40
Product Position
DAC / headphone amp / preamp
Balanced DAC / preamp
Tube DAC / headphone amp
DAC Chip
AK4493SEQ
ES9039Q2M
Not specified
USB Maximum
PCM 768kHz / DSD512
PCM 768kHz / DSD512
Lower-tier desktop decoding
HDMI ARC
No
Yes
No
Bluetooth
No
Yes
Yes
Analog RCA Input
Yes
No
No
Headphone Outputs
4.4mm, 6.35mm
None
3.5mm
Balanced XLR Output
Yes
Yes
No
Headphone Power at 32Ω
2570mW x2 balanced
Not applicable
250mW
Best Use
Complete headphone/desktop hub
TV and amplifier DAC hub
Compact tube headphone system
The Gustard H26 is a fully-balanced discrete Class-A headphone amplifier and preamplifier designed for high-end headphone and speaker systems. With dual gain modes, balanced and single-ended headphone outputs, and XLR/RCA preamp outputs, the H26 delivers clean, powerful amplification with exceptional linearity.
Why it stands out
Fully-Balanced Discrete Class-A Design
The H26 uses a fully-balanced discrete Class-A amplification circuit with hand-selected components, delivering the natural warmth and smoothness that Class-A operation is prized for, with exceptional linearity and low distortion across the entire frequency range.
High Power Output
Delivers up to 6W into 32Ω, 1576mW into 300Ω and 788mW into 600Ω, providing ample power for even the most demanding high-impedance headphones. Two selectable gain modes accommodate both sensitive IEMs and power-hungry full-size headphones.
Comprehensive Inputs & Outputs
RCA single-ended and XLR balanced inputs with selectable input sensitivity. Headphone outputs include 4-pin XLR balanced, 4.4mm balanced and 6.35mm single-ended. Preamp outputs (XLR and RCA, 100Ω output impedance) allow direct connection to power amplifiers or active speakers.
Premium Build & Remote Control
Solid aluminum chassis with premium components throughout. Frequency response extends to 80kHz (±0.1dB), SNR >123dB and channel crosstalk -123dB. Includes remote control for volume, input selection and gain switching.
Best for
High-end headphone systems, especially high-impedance full-size headphones
Listeners who want both headphone amp and preamp functionality
Systems with balanced XLR sources and headphones
Listeners who prefer Class-A amplification character
Not ideal for
Portable use — this is a full-size desktop unit requiring AC power
Systems needing built-in DAC (pair with a separate DAC)
Budget-conscious buyers
Specifications
Amplification
Fully-balanced discrete Class-A
Output Power (Balanced)
6W @ 32Ω, 1576mW @ 300Ω, 788mW @ 600Ω
Gain Modes
Two selectable gain levels
Headphone Outputs
4-pin XLR balanced, 4.4mm balanced, 6.35mm single-ended
Inputs
RCA single-ended (2-3Vrms, 4kΩ), XLR balanced (4-6Vrms, 8kΩ)
Preamp Outputs
XLR balanced & RCA single-ended (100Ω output impedance)
Frequency Response
20Hz-80kHz / ±0.1dB
SNR
>123dB
Channel Crosstalk
-123dB @ 1kHz
THD+N
<0.0002%
IMD
<0.0003%
Power
AC 115V/230V 50/60Hz, ~30W
Dimensions
W330 × D260 × H65mm
Weight
7kg (packaged)
FAQ
Q: Does the H26 have a built-in DAC?A: No, the H26 is a pure headphone amplifier and preamplifier. Pair it with a dedicated DAC such as the Gustard R26II or X26III.
Q: Can the H26 drive sensitive IEMs?A: Yes, the low gain mode and low output impedance make the H26 suitable for sensitive IEMs as well as full-size headphones.
Q: Can I use the H26 as a preamp for my power amplifier?A: Yes, the H26 features XLR and RCA preamp outputs with 100Ω output impedance, suitable for direct connection to power amplifiers or active speakers.
The Gustard R26 is a high-performance fully-discrete R2R DAC with built-in network streaming and Bluetooth, featuring USB, I²S, AES/EBU, coaxial and optical digital inputs with balanced XLR and single-ended RCA outputs. It delivers natural, musical R2R decoding in a compact desktop form factor with comprehensive connectivity.
Why it stands out
Fully Discrete R2R Architecture
The R26 uses a fully-discrete R2R resistor ladder network with hand-matched 0.01% precision resistors, delivering the natural, non-oversampling sound that R2R DACs are prized for — with exceptional midrange clarity, smooth treble and natural bass response.
Built-In Network Streaming & Bluetooth
Integrated network streamer supports Roon Ready, AirPlay, DLNA and UPnP for wired network playback. Bluetooth 5.0 connectivity provides convenient wireless streaming from mobile devices with high-quality audio codecs.
High-Resolution Support
Supports PCM up to 32-bit/768kHz and native DSD up to DSD512 (DSD256 DoP) via USB, I²S and LAN inputs. AES/EBU, coaxial and optical inputs support PCM up to 24-bit/192kHz and DSD64 DoP. MQA decoding is supported for streaming services.
Comprehensive Connectivity
USB-C and USB-B inputs, I²S (HDMI), AES/EBU, coaxial and optical digital inputs cover every source. Balanced XLR (5.0Vrms) and single-ended RCA (2.5Vrms) analog outputs connect to any amplifier or preamp. 10MHz external clock input allows synchronization with high-end clock sources.
Best for
Mid-range two-channel systems seeking R2R DAC character
Listeners who want both wired network and Bluetooth wireless streaming
Desktop or compact audio systems
Systems with balanced XLR or single-ended RCA amplification
Not ideal for
Systems requiring built-in headphone amplification
Listeners who prefer the analytical character of ESS/AKM DAC chips
Flagship-level systems that may benefit from the R26II or R30
Specifications
Architecture
Fully discrete R2R ladder
PCM
Up to 32-bit/768kHz (USB/I²S/LAN), 24-bit/192kHz (AES/Coax/Opt)
DSD
Up to DSD512 native (USB/I²S/LAN), DSD64 DoP (AES/Coax/Opt)
MQA
Supported (full decoder)
Bluetooth
5.0
Digital Inputs
USB-C, USB-B, I²S (HDMI), AES/EBU, Coaxial, Optical, LAN, Bluetooth
Clock Input
10MHz BNC
Analog Outputs
Balanced XLR (5.0Vrms), Single-ended RCA (2.5Vrms)
Frequency Response
20Hz-20kHz / ±0.2dB
Streaming
Roon Ready, AirPlay, DLNA, UPnP
Power
AC 115V/230V 50/60Hz, <60W
Dimensions
W330 × D260 × H65mm
Weight
7kg (packaged)
FAQ
Q: What is the difference between R26 and R26II?A: The R26II is an upgraded version featuring the GUSTARD-GCLK-02 clock module, improved digital filtering, Bluetooth 5.1 LDAC and enhanced overall performance. The original R26 remains an excellent R2R DAC with MQA support and comprehensive connectivity.
Q: Does the R26 support MQA?A: Yes, the R26 features full MQA decoding for compatible streaming services such as Tidal.
Q: Can I use an external word clock with the R26?A: Yes, the R26 has a 10MHz BNC clock input for synchronization with external high-end clock sources.
The Gustard R26II is a 26-bit fully-discrete R2R network streaming DAC with Bluetooth 5.1 LDAC, building on the acclaimed R26 platform with upgraded clock management, improved digital filtering and enhanced connectivity. It delivers natural, musical R2R decoding in a compact desktop form factor.
Why it stands out
26-Bit Fully Discrete R2R Architecture
The R26II uses a fully-discrete 26-bit R2R resistor ladder network with hand-matched components, delivering the natural, non-oversampling sound that R2R DACs are prized for — with exceptional midrange clarity and smooth treble.
GUSTARD-GCLK-02 Clock Module
The integrated GUSTARD-GCLK-02 synthesizer clock achieves ultra-low jitter performance at the femtosecond level, while preserving near-end performance of the reference clock. The high-precision divider ensures accurate frequency synthesis across all sample rates.
Bluetooth 5.1 LDAC & Network Streaming
Built-in Bluetooth 5.1 with LDAC support delivers high-quality wireless audio from compatible devices. The integrated network streamer supports Roon Ready, AirPlay, DLNA and UPnP for wired network playback.
Comprehensive Connectivity
USB-B, I²S (HDMI), AES/EBU, coaxial and optical digital inputs cover every source. Balanced XLR (5.0Vrms) and single-ended RCA (2.5Vrms) analog outputs connect to any amplifier or preamp. Includes remote control.
Best for
Mid-range two-channel systems seeking R2R DAC character
Listeners who want both wired and Bluetooth wireless connectivity
Network streaming setups with Roon or AirPlay
Desktop or compact audio systems
Not ideal for
Systems requiring built-in headphone amplification
Listeners who prefer the analytical character of ESS/AKM DAC chips
Flagship-level systems that may benefit from the R30
Specifications
Architecture
26-bit fully discrete R2R ladder
Clock
GUSTARD-GCLK-02 synthesizer clock module
PCM
Up to 32-bit/768kHz (USB/I²S/LAN)
DSD
Up to DSD512 (native), DSD256 (DoP)
Bluetooth
5.1 with LDAC
Digital Inputs
USB-B, I²S (HDMI), AES/EBU, Coaxial, Optical, LAN, Bluetooth
Analog Outputs
Balanced XLR (5.0Vrms), Single-ended RCA (2.5Vrms)
Frequency Response
20Hz-20kHz / ±0.2dB
Streaming
Roon Ready, AirPlay, DLNA, UPnP
Power
AC 115V/230V 50/60Hz, <20W
Dimensions
W330 × D260 × H65mm (including feet: 75mm)
Weight
7.3kg (packaged)
FAQ
Q: What is the difference between R26 and R26II?A: The R26II features the upgraded GUSTARD-GCLK-02 clock module, improved digital filtering, Bluetooth 5.1 LDAC and enhanced overall performance compared to the original R26.
Q: Does the R26II come with a remote control?A: Yes, the R26II includes a remote control for input selection, volume and filter settings.
Q: Can I use the R26II as a preamp?A: The R26II has fixed-level outputs. For volume control, use your amplifier or preamp.
The Gustard R30 is a flagship fully-discrete R2R network streaming DAC built around 27-bit resistor ladder architecture with an integrated OCXO oven-controlled crystal oscillator. It combines USB, I²S, coaxial, AES/EBU, optical and network streaming inputs with balanced XLR and single-ended RCA outputs for reference-grade digital-to-analog conversion.
Why it stands out
Fully Discrete 27-Bit R2R Architecture
Every signal-path component is an individual surface-mount resistor, capacitor and op-amp hand-selected by Gustard engineers — no integrated DAC chip. The 27-bit R2R ladder delivers natural, non-oversampling character with exceptional midrange purity.
Built-In OCXO Oven-Controlled Clock
An ultra-stable clock source maintained at constant temperature inside a sealed chamber reduces jitter below 5ps RMS across all sample rates, even during long playback sessions where ambient heat affects standard oscillators.
Native DSD1024 & PCM 1536kHz
Supports native DSD up to DSD1024 and PCM up to 1536kHz via I²S, with DSD512 and 768kHz over USB. Three selectable digital filter modes — Linear Sharp, Minimum Slow and Super Slow — let you tailor the presentation.
Network Streaming & Full Connectivity
Built-in network streamer supports Roon Ready, AirPlay, DLNA and UPnP. USB-B, I²S (HDMI), AES/EBU, coaxial and optical inputs cover every digital source, while balanced XLR (5.1Vrms) and RCA (2.5Vrms) outputs connect to any amplifier or preamp.
Best for
High-end two-channel systems seeking reference R2R decoding
Listeners who prefer natural, non-oversampling DAC character
Network streaming setups with Roon, AirPlay or DLNA
Systems with balanced XLR or single-ended RCA amplification
Not ideal for
Budget-conscious buyers — this is a flagship-level investment
Listeners who need built-in headphone amplification
Systems requiring MQA decoding (not supported)
Specifications
Architecture
27-bit fully discrete R2R ladder
Clock
Built-in OCXO oven-controlled crystal oscillator
PCM
Up to 1536kHz (I²S) / 768kHz (USB), 16-32bit
DSD
Up to DSD1024 (I²S) / DSD512 (USB), native & DoP
Digital Inputs
USB-B, I²S (HDMI), AES/EBU, Coaxial, Optical, LAN (RJ45)
Analog Outputs
Balanced XLR (5.1Vrms), Single-ended RCA (2.5Vrms)
Dynamic Range
>123dB
SNR
>121dB
THD+N
≤0.00145% @ 1kHz
Frequency Response
20Hz-20kHz / ±0.2dB
Streaming
Roon Ready, AirPlay, DLNA, UPnP
Power
AC 115V/230V 50/60Hz, <35W
Dimensions
W430 × D300 × H80mm (including feet)
Weight
10kg (packaged)
FAQ
Q: Does the R30 have a built-in headphone amp?A: No, the R30 is a pure DAC/preamp. Pair it with a dedicated headphone amplifier or integrated amplifier.
Q: Can I use an external word clock?A: The R30 has a built-in OCXO clock. External clock input depends on specific configuration — refer to the user manual.
Q: Is Roon Ready included?A: Yes, the R30 is Roon Ready certified for seamless network streaming.
The Gustard U26 is a high-performance USB digital interface (DDC) designed in collaboration with Amanero Technologies. It transforms USB input into ultra-precise digital output for your DAC through IIS (I²S), AES/EBU or coaxial connections, with an SC-cut OCXO master clock and K2 high-performance PLL synthesis for femtosecond-level jitter performance.
Why it stands out
Gustard × Amanero Custom USB Engine
Developed in collaboration with Amanero Technologies, the U26 uses a custom UAC2 USB audio engine powered by an ARM Cortex-M7 (i.MX RT1011) processor. The ASIO driver with buffer/latency controls ensures optimal performance for Windows-based audio systems.
SC-Cut OCXO Master Clock
An SC-cut OCXO (Oven-Controlled Crystal Oscillator) master clock combined with the K2 high-performance PLL synthesis (98.3040/90.3168 MHz) achieves ultra-low jitter at the femtosecond level, ensuring precise clocking for your DAC regardless of the source clock quality.
High-Resolution Support
Supports PCM up to 32-bit/384kHz and DSD up to DSD256 (DoP) via coaxial and AES/EBU outputs. IIS (I²S) output supports even higher rates depending on your DAC's capabilities. A 10MHz BNC input allows synchronization with external clock sources.
Linear Power Supply & Premium Build
Linear power supply with audio-grade toroidal transformer, dual rectifier bridges, discrete regulation and ultra-low-noise LDOs, with 80,000µF primary filtering. Full aluminum alloy enclosure with EMI shielding. Digital outputs include IIS (HDMI), AES/EBU (XLR), coaxial (RCA) and a 10MHz BNC clock input.
Best for
Audiophiles with high-end DACs who want to improve USB input quality
Systems where the computer's USB output is a bottleneck
Listeners who want to add IIS (I²S) output to a USB-only source
Setups requiring external clock synchronization (10MHz BNC input)
Not ideal for
Casual listeners — a DDC is a specialized component for serious audiophiles
Systems where the DAC already has an excellent USB input (diminishing returns)
Budget-conscious buyers
Specifications
USB Engine
Gustard × Amanero custom UAC2, ARM Cortex-M7 (i.MX RT1011)
Clock System
SC-cut OCXO master clock + K2 PLL synthesis (98.3040/90.3168 MHz)
USB Input
USB Type-B (female), USB 2.0
PCM
Up to 32-bit/384kHz (coaxial/AES), higher via IIS
DSD
Up to DSD256 (DoP) via coaxial/AES
Digital Outputs
IIS (HDMI), AES/EBU (XLR), Coaxial (RCA, 75Ω)
Clock Input
10MHz BNC (50Ω, 0dBm-20dBm)
Coaxial Output Level
≥500mV P-P @ 75Ω load
Power Supply
Linear PSU with toroidal transformer, 80,000µF filtering
Power
AC 115V/230V 50/60Hz, <15W
Dimensions
W330 × D260 × H65mm
Weight
4.8kg (net), 6.3kg (packaged)
FAQ
Q: What is a USB digital interface (DDC)?A: A DDC (Digital-to-Digital Converter) takes USB input from your computer and converts it to standard digital outputs (IIS, AES/EBU, coaxial) with improved clocking, connecting to your DAC's digital inputs. It improves sound quality by isolating the DAC from computer noise and providing a cleaner clock signal.
Q: Do I need a DDC if my DAC already has USB?A: If your DAC has a high-quality USB input (e.g., with XMOS interface), a DDC may provide diminishing returns. However, for DACs with mediocre USB inputs or for IIS (I²S) connection, a DDC can provide significant improvement.
Q: Does the U26 require driver installation?A: The U26 uses UAC2 (USB Audio Class 2), which is natively supported by macOS and Linux. Windows requires the ASIO driver provided by Gustard/Amanero.
The Gustard X26III is a flagship-level desktop DAC featuring dual ESS ES9039SPRO DAC chips in a fully-balanced configuration, with DSP autonomous digital filtering, FPGA programming logic and the GCLK-02 clock module. Built-in network streaming makes it a complete digital hub for high-end audio systems.
Why it stands out
Dual ES9039SPRO DAC Chips
Two ESS ES9039SPRO chips in fully-balanced dual-mono configuration deliver exceptional dynamic range (>128dB), ultra-low THD+N (≤0.0001%) and precise channel separation (-132dB). The hybrid IV conversion and discrete analog LPF circuits ensure optimal analog output performance.
DSP Autonomous Digital Filtering
Analog Devices SHARC DSP handles autonomous digital filtering with multiple selectable filter profiles, letting you tailor the sound to your preference — from sharp linear-phase to slow minimum-phase rolloff.
GCLK-02 Clock & FPGA Control
The GUSTARD GCLK-02 clock module provides ultra-low jitter clocking, while the proprietary FPGA programming logic chip manages digital signal processing and interface control with precision and flexibility.
Network Streaming & Full Connectivity
Built-in network streamer with Roon Ready, AirPlay, DLNA and UPnP support. USB-B (XMOS XU216), I²S (HDMI), AES/EBU, coaxial and optical inputs cover every digital source. Balanced XLR (5.1Vrms) and RCA outputs connect to any amplifier.
Best for
High-end desktop or compact audio systems seeking flagship ESS DAC performance
Listeners who want selectable digital filtering profiles
Network streaming setups with Roon or AirPlay
Systems with balanced XLR amplification
Not ideal for
Listeners who prefer R2R DAC character (see R26II or R30)
Systems requiring built-in headphone amplification
Budget-conscious buyers
Specifications
DAC Chips
2× ESS ES9039SPRO (fully-balanced dual-mono)
DSP
Analog Devices SHARC DSP (autonomous digital filtering)
FPGA
Proprietary FPGA programming logic
Clock
GUSTARD GCLK-02 clock module
USB Interface
XMOS XU216
PCM
Up to 32-bit/768kHz
DSD
Up to DSD512
Digital Inputs
USB-B, I²S (HDMI), AES/EBU, Coaxial, Optical, LAN
Analog Outputs
Balanced XLR (5.1Vrms), Single-ended RCA
Dynamic Range
>128dB
SNR
>126dB
THD+N
≤0.0001% @ 1kHz
Channel Crosstalk
-132dB @ 1kHz
Streaming
Roon Ready, AirPlay, DLNA, UPnP, Spotify Connect
Power
AC 115V/230V 50/60Hz, <25W
Dimensions
W330 × D260 × H65mm
Weight
7.5kg (packaged)
FAQ
Q: How does the X26III compare to the R26II?A: The X26III uses dual ESS ES9039SPRO chips for a detailed, analytical presentation with DSP digital filtering. The R26II uses fully-discrete R2R architecture for a warmer, more natural sound. Both are similarly priced and feature network streaming.
Q: Does the X26III support MQA?A: MQA support may vary by firmware version. Refer to the latest specifications for confirmation.
Q: Is the X26III Roon Ready?A: Yes, the X26III features built-in network streaming with Roon Ready certification.
The Gustard X30 is a flagship desktop DAC equipped with four ESS ES9039SPRO DAC chips in a fully-balanced dual-mono configuration, an ES9311Q dedicated linear regulator and a second-generation XMOS XU216 USB interface. With built-in network streaming, it delivers reference-level digital-to-analog conversion for high-end audio systems.
Why it stands out
Quad ES9039SPRO DAC Chips
Four ESS ES9039SPRO chips arranged in dual-mono fully-balanced configuration deliver exceptional dynamic range, ultra-low distortion and precise channel separation. The ES9311Q dedicated linear regulator ensures clean, stable power to the DAC stage.
Second-Gen XMOS XU216 USB Interface
The upgraded XMOS XU216 USB audio interface supports PCM up to 32-bit/768kHz and DSD up to DSD512 natively, with ultra-low latency and robust driver support for Windows, macOS and Linux.
Built-In Network Streaming
Integrated network streamer with Roon Ready, AirPlay, DLNA and UPnP support lets you stream directly from your network without an external streamer. Ethernet and Wi-Fi connectivity provide flexible installation options.
Premium Build & Full Connectivity
Solid aluminum chassis with premium components throughout. USB-B, I²S (HDMI), AES/EBU, coaxial and optical digital inputs cover every source, while balanced XLR and single-ended RCA outputs connect to any amplifier.
Best for
High-end two-channel systems seeking flagship ESS DAC performance
Listeners who prefer the analytical, detailed character of ESS chips
Network streaming setups with Roon or AirPlay
Systems with balanced XLR amplification
Not ideal for
Listeners who prefer the warmer character of R2R DACs
Budget-conscious buyers
Systems requiring built-in headphone amplification
Specifications
DAC Chips
4× ESS ES9039SPRO (dual-mono fully-balanced)
Regulator
ES9311Q dedicated linear regulator
USB Interface
XMOS XU216 (2nd generation)
PCM
Up to 32-bit/768kHz
DSD
Up to DSD512 (native & DoP)
Digital Inputs
USB-B, I²S (HDMI), AES/EBU, Coaxial, Optical, LAN
Analog Outputs
Balanced XLR, Single-ended RCA
THD+N
≤0.0001% @ 1kHz
Streaming
Roon Ready, AirPlay, DLNA, UPnP
Power
AC 115V/230V 50/60Hz, <30W
Dimensions
W430 × D300 × H80mm (including feet)
Weight
10kg (packaged)
FAQ
Q: How does the X30 compare to the R30?A: The X30 uses four ESS ES9039SPRO chips for a detailed, analytical presentation, while the R30 uses fully-discrete R2R architecture for a warmer, more natural sound. Both are flagship-level DACs.
Q: Does the X30 support MQA?A: MQA support depends on firmware. Refer to the latest specifications for confirmation.
Q: Is the X30 Roon Ready?A: Yes, the X30 features built-in network streaming with Roon Ready certification.