Fosi Audio Q4 DAC Headphone Amp for PC, Desktop Digital to Analog Audio Converter for Home Stereo Amplifier and Powered Speakers, PC-USB/Optical/Coaxial Inputs, 3.5mm Headphone/RCA Outputs

Price: $69.99
(as of Jun 28, 2025 23:27:59 UTC – Details)

Product Description

Literally Plug and Play Fosi Audio Q4 DAC & Headphone Amplifier

A compact and lightweight, user-friendly desktop audio device.

Your Sound Perception Will be Revolutionized

Q4 is an entry-level all-in-one DAC and headphone amplifier. It is plug-and-play and does not require any driver. It has the characteristics of high signal-to-noise ratio and low distortion.

PC-USB Sampling Frequency: 24bit/96kHzOptical/Coaxial Sampling Rates: 24bit/192kHzSNR: >105dB; THD: 0.01%; Bass and Treble Range: ±6dBOperation Systems: XP/Win7/Win8/Win10/Win11/MAC/Linux

Accommodate Various Home Audio Systems

Equipped with USB/Optical/Coaxial inputs and RCA/Headphone outputs for diverse connection needs.

DAC + Headphone Amplifier

A compact, lightweight, and user-friendly desktop device that adapts to your varied needs.

Perfect for Gaming

Low latency and an outstanding sound stage provide an incomparable feeling of immersion.

A Little Gem for Music Lovers

SNR up to 105dB keeps the sound clear and pure at all times and effectively resists interference.

1 Home Audio System

2 Desktop Device

3 Low Latency

4 Anti-Interference

1 Bass & Treble Controls

2 Audio Ports

3 Corner Design

Can Q4 output analog stereo audio through both the 3.5mm headphone jack and the RCA red/white jacks at the same time?

Q4 will mute the RCA output when headphones are plugged in.

How do I connect Q4 to my computer with USB input?

Your other USB cables must support OTG function.

-For iPhone: Use a USB B to Lightning OTG Cable.

-For Android: Use a USB B to TYPE C Cable.

Where is the 0db position (Q4)?

The 0db position is at 12 o’clock on the knob.

Does Q4 support PS5?

Yes, it supports PS5.

Can RCA output be connected to a soundbar (e.g., AUX input) (Q4)?

Yes, it can work.

Quick Troubleshooting Guide

1. Common Audio Issues

– One Channel Has Sound or Unbalanced Output: Ensure all cables are securely connected. Test with different cables and input modes. For RCA output, check speaker connections. For headphones, ensure the jack is fully inserted and try different headphones.

– No Sound from USB: Use different USB cables and ports. Restart your computer and select the correct sound output device (e.g., HIFI Audio). Update or reinstall the USB driver.

– White Noise or Static: Set the volume to 50% or lower. Ensure all cables are securely connected and test for interference from nearby devices. Use well-shielded cables and try different input modes. For headphones, use high-impedance headphones to reduce noise.

2. Connection and Compatibility

– Connecting to a Computer: Ensure your USB cables support the OTG function. For iPhone, use a USB B to Lightning OTG Cable. For Android, use a USB B to Type-C Cable. Follow the setup guide for detailed instructions.

– Connecting to a TV: Use a coaxial or optical cable. Ensure the TV is set to PCM/RAW mode and disable Dolby or DTS sound. Follow the setup guide for detailed instructions.

– Power Issues: Ensure a stable power supply. Replace the power cable or adapter if necessary. Refer to the tutorial video for guidance.

3. General Tips: Driver Updates: If you encounter driver errors, update to the latest Microsoft driver (KB5050094) for compatibility. Volume Control: The TV remote cannot control the Q4 volume when connected via optical or coaxial. Use the Q4 volume knob instead.

Your Guide to Choosing the Right Headphone Amplifier

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Customer Reviews

4.4 out of 5 stars 3,034

4.2 out of 5 stars 1,042

4.5 out of 5 stars 304

4.4 out of 5 stars 194

4.5 out of 5 stars 570

4.7 out of 5 stars 66

4.3 out of 5 stars 168

Price

$69.99$69.99

$79.99$79.99

$79.99$79.99

$99.99$99.99

$29.99$29.99

$49.99$49.99

$59.99$59.99

Type

DAC+Headphone Amp

DAC+Headphone Amp

Headphone Amplifier/Preamp

DAC+Headphone Amplifier/Preamp

Headphone Amp

Headphone Amp

DAC+Headphone Amp

MAX Power Output

–

–

2400mW@32Ω(High Gain)

3.5mm: 280mW,4.4mm: 1100mW@32Ω

40mW@100 Ohm

310mW@32Ω

120mW@32 Ohm(SE)

Input

PC-USB+OPT+COA

USB-C+OPT+COA+3.5mm Microphone

3.5mm line in

USB + Optical

3.5mm AUX

3.5mm AUX

Type C+ USB A

Output

RCA + 3.5mm Headphone

RCA + 3.5mm Headphone

line out, 3.5/6.35mm headphone

3.5/4.4mm Headphone, AUX/OPT

3.5mm Headphone ×4

3.5mm Headphone ×5

3.5mm & 4.4mm Headphone

Treble & Bass Control

✔

✔

✔

✘

✘

✘

✘

THD

≤0.01%

<0.003%

<0.001%

<0.001%

–

<0.001%

<0.0001%

SNR

≥105dB

>110dB

≥108dB

≥120dB

–

≥105dB

≥130dB

Terminating Impedance

16-200 Ohm

16-300 Ohm

16-300 Ohm

16-300 Ohm

15-150 Ohm

16-300 Ohm

16-300 Ohm

Work Voltage

DC 5V

USB-C/DC5V

USB-C/DC5V

USB-C/DC5V

12V/1.5A

–

–

Versatile Entry-Level: The Fosi Audio Q4 is an entry-level DAC and headphone amp, featuring USB, Optical, and Coaxial inputs, plus RCA and 3.5mm outputs. It drives headphones from 16Ω to 200Ω, enhances audio quality, and connects to speakers or amplifiers
Plug-and-Play Convenience: Instant HiFi audio with no driver installation. Connect to TVs, computers, speaker systems, or DVD players. Compact design fits anywhere, offering ultimate audio freedom
Bass and Treble Controls: Adjustable bass and treble knobs for fine-tuning sound. Natural feel with smooth volume adjustment. High-quality metal knobs for a premium experience. Optimize audio for any source
Compact and High-Quality: Compact DAC converter with full metallic shell. Supports 24-bit/192kHz HD audio with low jitter. Includes output protection circuit for system safety
Complete Accessories: Includes USB charging cable, optical cable, and PC-USB to Type-B cable. Ensures hassle-free setup and immediate use. Seamless connectivity for various devices. (Note: No microphone input.)