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
Original price was: €70.€63Current price is: €63.
Price: $69.99 - $62.99
(as of Aug 02, 2025 18:20:45 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 3,048
4.2 out of 5 stars 1,090
4.5 out of 5 stars 326
4.4 out of 5 stars 204
4.5 out of 5 stars 581
4.7 out of 5 stars 72
4.3 out of 5 stars 192
Price
$62.99$62.99
$79.99$79.99
$75.99$75.99
$99.99$99.99
$27.33$27.33
$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.)
8 reviews for 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
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Related Products
Original price was: €70.€63Current price is: €63.
Nobody –
A tenative review, we’ll see if it lives. Let’s give it the final star.
After losing five $20-30 headphone amplifiers in a row, within days or weeks, just because we’re tripling the cost here doesn’t necessary mean this will do better. In the q&a section one person warned me it died within two months, another person says it’s been running for two years. Why a solid state device should have any life is beyond me, my beloved 50+ year old Nakamichi RE-3 receiver is still running fine.My question was, since this does not have a 3.5 audio input, can it be fed by a PC into the coaxial input with a converter? Four people said yes, one said no. It’s no. So, what use is a 3.5 to coaxial conversion plug? Never mind. Since I cannot get my Dell running Windows 10 to put any sound into this through the USB route, it’s useless, to me at least, as a PC headphone driver. One of the days I suppose I should get the headphone jack fixed, it’s dead for some reason. Still working on that, the last headphone amp I had died, so my PC is going through the Nakamichi for awhile, rather clumsy.I also need an amp for my new Vizio TV. It also has a 3.5 audio out, forget about that. Therefore, I hooked up the optical input, and nothing, no sound at all. I checked all the connections, seemed to be okay, but just before I ripped it out to send it back to Azon, the darn thing turned on. Is there a warm-up delay?? It will be on all the time, so hopefully it will keep running.One other slight problem, the cords are absurdly too short, the optical cable isn’t even as long as my TV. No biggie of course, but if you’re going to put cords in the box, at least make them long enough to be useful.So, I’ll live with this for awhile, and then edit the review . . . one way or the other.Ed: One thing, normally I set the volume control at about 75% on everything, and adjust the volume to my earphones through an in-line control. When set like that, I was picking up sputtering sounds on some Youboob videos, but it was fine on video files played from a USB stick (the only two ways I use the TV). Youevil volumes are much higher than typical USB files, I knew that, and the USB files play fine. I was not picking up any problems on my PC, so I switched out everything, the in-line volume wheel controls, the earphones, both combinations, and it was definitely something in the TV audio.I turns out I had the volume set waaaay too high on the Fosi box, with the in-line control taken out, the headphones were blasting. I played around with the volume knob, and lo and behold, the sputtering sounds went away. I had to fine tune it so the in-line control had enough room with both Eviltube and USB sources, which worked out to be around 55%. If you’re having problems, you might try turning it down. Note, the variable audio output on my TV does not work if you plug in something to the optical output, so unless you want to get up off the couch every 30 seconds to adjust the Fosi volume, in-line controls are a must for my setup. They’re very cheap, but buy them by the handful, they wear out. They work very well with YT when you run into a commercial, you can cut the volume to zero instantly.Ed: I’ll bump it a star, for two reasons. First, the original unit I bought is still alive, and in the headphone amplifier world, that seems to be a real accomplishment. And, I bought another one for my 2015 Vizio, now relegated to the bedroom, and it fired up and worked as well, on optical. So now I have two of them, and I’ll see how long they last. Maybe someday down the road this will get the final star.Also wik: Two months now, one is on 24/7, the other with the second TV off and on. No problems. That should be long enough for any glitches to show up.
A & B –
Awesome Amplifier
Great cheap amp that is small and easy to setup. Bought this for my gaming computer as onboard audio just wasn’t enough. Great for music, gaming and you tube. Audio is clear and have no issues with distortion. It is small and good to stick underneath a desk or off to the side when it needs to be adjusted.
Amazon Customer –
Good if you’re planning on using S/PDIF or Toslink, not so much USB
The most important thing I want to note is that the USB-C 5V power input is REQUIRED. You will not be able to power this thing through the USB-B port used for data from a computer. Many other USB audio interfaces on the market, including large ones, can be powered from their host computer over USB in a pinch, but this one does not offer that feature. It also has pretty terrible isolation (which is probably why they split out power and data like that), so powering it from a second port on your computer will make it very noisy. Expect to have to dedicate an outlet (and a USB power supply, not included) to this thing. Also, make sure it’s not a USB-C power supply, because the USB-C implementation is flawed and it lacks the internal resistors necessary to activate a USB-C port.Given all of this, I probably would have sent it back, had I not unexpectedly discovered that my computer has a Toslink optical output, and the vendor of this product was so kind as to include a Toslink cable in the box. When powered from an old phone charger and given signal over Toslink, everything works great, and it’s really quite a decent amplifier once you get over the power hurdles. The knobs are smooth, bass/treble separation is decent, and it has plenty of power. I bought it mainly because I needed a way to keep my bass under control in a thin-walled apartment, and it works quite well for that.Bottom line: if you’re intending to use it with an optical or coaxial S/PDIF output, I’d recommend it, but if you want something quick and easy that can be run over one USB cable, this isn’t what you’re looking for.
H. Carter –
Having previously purchased two âcheapâ DAC Converter units and really struggled to get any decent level of sound through them, I decided to bite the bullet and pay a bit more for the Fosi Audio Q4 Headphone Amplifier DAC Converter. I am using this unit with a TosLink optical cable and it has exceeded all my expectations. This little device punches above its weight and delivers a remarkable listening experience that I think would be hard to match in its price range.It is a very compact and sturdy design, with a solid and premium feel to it.I am using this device with an LG Smart TV that is fitted into a bed unit (so TV rises from foot of the bed). As such, we only ever use this TV with headphones, so achieving decent sound through headphones is essential to us. As previously mentioned, I had struggled to get any decent level of sound through two cheaper versions of DAC converters (the sound levels were so quiet we had resorted to always using subtitles when watching TV), but I just left the cables in place that were used with those and plugged them into the Fosi unit â which clearly showed me there was nothing wrong with the cables I had been using and the issue was with the cheap DAC units. With the Fosi unit, everything works brilliantly and the sound quality and levels are awesome. I am not using particularly expensive headphones â they are wired and have an impedance value of 32 â which should have been good enough with the original âcheapâ DAC converter but simply wasnâtThe Fosi Audio Q4 Headphone Amplifier DAC Converter is an absolute gem â although it should be noted I have only tried connecting via Toslink optical cable so cannot comment on other connection options. Itâs hard to believe that such a small, affordable device can provide this level of audio performance. Highly recommended!
Fahad –
٠٠تاز
Victor A. –
Bonjour !J’ai fait l’acquistion de ce DAC Ampli car la carte son intégré de mon pc ne me permettait pas de profiter correctement de mon nouveau casque, le DT 770 Pro.J’ai commencé mes recherches en ayant aucune connaissance dans le milieu de l’audio, pour être honnête, je ne suis pas plus avancé à l’heure qu’il est mais, mon budget et mes critères m’ont amené à ce produit.Beaucoup d’avis internationaux, beaucoup d’avis assez incomplet, c’est pour cela que je vais essayer de faire de mon mieux pour vous décrire le produit.La première chose à savoir est que l’alimentation du DAC se fait via un cable micro usb, cela m’a déstabilisé au début, le câble USB-MIDI ne servant qu’à faire le lien entre le DAC et l’appareil utilisé (ici mon ordinateur).L’installation sur mon PC s’est fait automatiquement : une fois branché, le driver s’est installé automatiquement et mon pc l’a reconnu.Niveau connectique du casque, c’est une entrée Jack 3.5mm.Il y a 3 modes réglable via un petit “levier” : USB, Optique et Coaxial. Ne connaissant et n’uitilisant pas les deux derniers, je vous donne uniquement mon avis sur l’utilisation USB.Le produit en lui-même a selon moi un aspect assez qualitatif, finition en métal, les différents boutons sont solides et agréables à utiliser.NIVEAU SON maintenant, c’est là où mon manque d’expertise va entrer en jeu malheureusement, je ne pourrais pas vous donner d’aspects vraiment technique sur le rendu du son etc, je vais donc juste vous faire un comparatif entre l’utilisation de mon casque avant de faire l’acquisition du produit et une fois le produit acquis.Mon casque a une impédance de 80 Ohms, mais la carte son intégré à ma carte mère (Asus TUF B450M Plus Gaming), n’était clairement pas suffisante pour pousser le casque correctement : le son était très faible, il y avait des petites interférences, assez rares mais assez embêtantes avec un casque de cette qualité, le son saturait rapidement malgré un niveau de son en dB assez faible… et le son paraissait très étouffé.Une fois le DAC Ampli installé, sans même toucher aux boutons permettant de régler les basses et les aigus, le rendu audio s’est métamorphosé :- Son beaucoup plus clair, plus net;- Volume très puissant, réglable facilement via la “molette” de volume qui par ailleurs est très agréable à utiliser;- Le correcteur de tonalité (ajustement des graves et aigus) joue vraiment beaucoup dans la plus value de ce produit selon moi : il offre un très bon rendu, vous permet d’ajuster vos écoutes selon vos préférences et le type de musiques écouté;- J’ai enfin pu découvrir les basses de mon casque qui ont un rendu vraiment prenant.Conclusion :Je ne suis pas audiophile pour un sous, mais j’adore écouter de la musique, et ce DAC Ampli combiné à mon casque m’ont fait re découvrir des musiques que j’écoute depuis des années. C’est la première fois de ma vie que j’ai l’occasion d’écouter de la musique avec une qualité pareil, ce sont les petits détails qui changent toute l’expérience. Je ne peux que recommander ce produit au vu de son prix, sa qualité et ses fonctionnalités.Le seul “inconvénient” (qui n’en est pas un pour moi) du produit peut être l’alimentation, qui se fait par Micro USB.J’espère avoir pu vous aider via cet avis, ceux qui sont dans ma situation et qui cherchent un DAC Ampli pour driver un casque sur PC notamment, foncez !
Max –
Ordine gestito molto velocemente, arrivato perfetto e funzionante. L’impatto sonoro è stato buono, visto che il dac fà da tramite scheda audio-ampli anni 80. Poi il meglio sono state le regolazioni dei toni, che danno un boost all’amplificazione. Prodotto di una certa caratura,consigliato
Maria Puga Flores –
Lo use para conectar la tv a un estéreo sony genezi fst-2000, la tv al fosi audio q4 lo conecte a través del cable óptico y luego del dac fosi q4 al estéreo sony genezi vÃa rca. El audio mejor notablemente y lo mejor fue que se se pudo ecualizar los agudos que es el motivo principal por el que adquirà este equipo ya que el sony fst-2000 daba un sonido de audio con graves muy fuertes, con este equipo solucione mi problema de los agudos y se escucha muy bien. Ya puedo ecualizar la música a mi gusto graves, agudos y volumen. Recomiendo este equipo si lo buscas para un propósito similar, su diseño es pequeño cabe en la palma de la mano es bueno porque no es voluminoso y cabe en cualquier lugar para instalarse, los materiales son robustos y de calidad. Como fuente de energÃa utilice la entrada usb de 500mA 5v de mi tv y levanto sin problema al equipo dac fosi q4.