

🎧 Tiny Amp, Massive Impact: Power Your Sound Like a Pro
The Fosi Audio ZA3 is a compact yet powerful Class-D stereo amplifier delivering up to 180W per channel in stereo and 235W in mono mode. Featuring balanced XLR/TRS inputs and a 12V trigger for seamless integration, it uses premium audiophile-grade components for exceptional clarity and low noise. Its advanced heat dissipation design ensures reliable high-power output, while swappable op-amps let you customize your sound. Perfect for desktop setups, home theaters, and bookshelf speakers, the ZA3 combines professional-grade performance with sleek, space-saving design.























| ASIN | B0CLP4T5L7 |
| Best Sellers Rank | #6,273 in Electronics ( See Top 100 in Electronics ) #18 in Audio Component Amplifiers |
| Brand Name | Fosi Audio |
| Customer Reviews | 4.6 out of 5 stars 998 Reviews |
| Included Components | Fosi Audio ZA3 Power Amplifier x1;48V5A Power Adapter x1;User Manual x1 |
| Item Dimensions | 6.1 x 7.24 x 2 inches |
| Item Weight | 1.2 Kilograms |
| Item dimensions L x W x H | 6.1 x 7.24 x 2 inches |
| Manufacturer | Fosi Audio |
| Maximum Supply Voltage | 48 Volts (DC) |
| Minimum Supply Voltage | 24 Volts (DC) |
| Model | ZA3 |
| Mounting Type | Surface Mount |
| Number of Channels | 2 |
| Output Power | 235 Watts |
| Package Type Name | Cardboard Box |
| Specification Met | FCC |
| Voltage | 48 Volts |
| Warranty Description | 24-month manufacturer |
N**O
Very satisfied but watch out for setup traps
I was replacing an older NAD integrated amp that I really liked. Decided to go class D amp for a replacement. WAY smaller. MUCH less expensive, and this unit has all the functionalities I was looking for at an incredible price (I bought mine for about $130 each on Amazon. Will be using two in mono mode. At first I thought they were defective. PAY ATTENTION TO THE MANUAL THAT WARNS YOU TO CONNECT ALL CABLING BEFORE YOU INSERT THE POWER CONNECTION. If you power the device first, then attach cables, it won't work at all until you detach the power cable and reinsert it. This is no fluke. It happened several times. Attach ALL cabling first, then insert the power connection. Secondly, if you're running it in mono mode the inputs for both units are inserted into the RIGHT side on the rear of the unit. The left channel is disabled in mono mode. This is all spelled out in the manual but it's counter-intuitive at first. As for sound, I'm pleased. I'm sending Tidal or Spotify digital signals to a Fosi ZD3 via bluetooth (works perfectly). The ZD3 is the DAC and connects to the paired Za3s. My speakers are very modest, a HSU powered sub that I've connected to the ZD3 (not the ZA3). Main speakers are HSU HB1 mk2. The ease of use with my iPhone is just fantastic. Essentially any song I want is at my fingertips. Sound quality is very good to my untrained ears. I'm very happy with this purchase. These amps have more than enough power to drive these smaller speakers even at higher volumes than I'd ever naturally want. The fit and finish of the amps is very good. No noise in the volume knob at all but I leave them in a fixed position adjusting volume either at the ZD3 "preamp" or even more commonly with my iPhone volume controls. I've been buying / building stereo equipment for about 55 years. I'm a huge music fan, but I can't hear all the mumbo-jumbo the experts can. I just know these are great little amps for an incredible price, and even one would work nicely in stereo mode. Very happy. Will see how they stand up to time and use.
V**N
Tiny but Mighty! Simply Awesome. BUY IT!
Tiny but Mighty! Simply Awesome. Incredible value for money. Performance, quality, power, clarity, resolution, size, look, ease of installation (hint: there is none; plug it in and go!) - all great! Using it for my desktop amp; sounds way better than my powered JBL studio monitors. They're so inexpensive, I think I will add another one, and make mono blocks of them. I first saw/heard about these from cheapaudioman on YouTube. For the price, I had to try it, and I'm glad I did. They drive everything I've thrown on them - including 4 ohm speakers. It's phenomenal; sounds really good! 180 watts per channel (will be 230 watts/channel in mono mode!) and it's the size of my Mac Mini. Crazy good. Hat tip to cheapaudioman - you were dead on, a great recommendation!
D**H
Plenty of power, sounds nice, good support (firmware updates)
Great little amp. My stack is a Wiim amp pro (for streaming and eq), Fosi ZD3 preamp, and Fosi ZA3 with the 48v power supply running in stereo mode. Mostly run from an apple tv sending hdmi to the tv then optical from there. The whole setup was easily under $500. I chose this setup in case I needed more power, I can simply add another amp and run mono, but it's definitely not needed. Runs a pair of Q Accoustic 5020s easily to unlistenable levels in a small/med size room (450sq/ft). I have the whole stack switched with a smart plug and haven't had any issues with powering off or on (unlike my last set of powered Swans speakers which blew up on power up). I was occasionally getting a little pop on power up and also a computerized "bzzzrt" very occasionally during listening. I just googled and found there was a firmware update for the Preamp (no issue with the amp). Just contact Fosi support and they give you the url for the updated firmware. Easy to install with a windows laptop and usb cord. Haven't had either issue since. Really nice to see firmware updates so quickly! So used to products this cheap being treated as "disposable" and not getting real support. I'm very happy with the performance and the support. I think it really helps that there seems to be a lot of love in the stereo community for this and other Fosi products. I hope it continues to get firmware updates in the future. The set looks really clean and very minimal. Used to do the whole rack or shelf system of components, but I'm over it. Most recently, I was using a set of powered speakers because I like not seeing the electronics. But when those failed you basically throw the whole thing away. I eventually had them fixed, but I don't like the idea of a failure being a total loss. So now I like having small separate pieces. I absolutely love the size. Even though the Fosi set looks very nice, I now have my entire multimedia set up hidden behind a small chest and subwoofer as shown in the last picture (please ignore my weird music choice). There is one downer on this product. It has a sub out which is great. But when you connect a subwoofer, it still sends full signal to the speaker outs. At high volumes you can hear the small bookshelf speakers trying to put out bass that's not really needed with a sub. Edit: I forgot my SVS subwoofer has a high pass eq! So now I have the preamp go into the subwoofer and pass through to the amp. The sub out should really be on the preamp not the amp. Weird choice.
R**O
Great little amp with WIIM Ultra Streamer
This thing is strong enough to power 2 KEF LS50 Metas to a loud level. Works great connected with WIIM Ultra streamer.
A**R
Great little Amp
So I waited to do a review on this item. To be honest first impression was horrible was basically thinking about sending it back. I had to down size my computer audio set up due to a move but wanted something better then computer speakers so I order this amp to power a couple sony home theater in a box speakers that my parents had and wern't using. The sound was horrible I was thinking it was due to the amp, I couldnt have been more wrong. Decided to dig out my B&W 685's which are my original computer speakers and hooked them up to the amp and wow night and day difference. Needless to say I made room to use my speakers cant use my original amp due to restrictions in space but honestly Im so impressed with this little amp im thinking about getting another one and running them in mono. If you want a nice compact amp to power some speakers I would highly recommend this amp. Pair it with some good speakers and it will serve you well. My set up is a audio quest dragon fly cobalt out to this amp, 10 inch svs sub and my B&W685's sound is really good and plenty of power. My pc now has the sound I wanted in the first place.
H**.
Desktop Amp for computer.
Since the end of June 2025, using the ZA3 to drive a pair of Polk Signature Elite ES10 Surround Sound Speakers from my Mac Studio M2 via the headphone jack. Volume on the ZA3 set to approximately 90% of max at all times as I am controlling volume from the MacOS. No audible noise when music is paused. Using as a desktop sound system with the speakers a bit above ear level, at distance of about 2.5ft, when I am seated at the keyboard. Plenty loud in this configuration with good imaging. I suspect it may not be enough to fill a large room. Prior to purchasing the ZA3 I was using an old Onkyo stereo receiver and I have no desire to go back. It's no audiophile system but easily beats cheap PC speakers. Just listened to Dire Straits Money for Nothing with the drum solo at the beginning and it is nice and tight. No regrets. Well OK not as good as my modded Hafler amp putting 450W/channel into Kef 104/2 Reference Series floor standers and a SVS sub, but that's a whole other league (and doesn't fit on a desk).
M**N
Great value piece
Amazing for the price. On a budget, this should be the go-to amp. It’s powering a pair of mid-range passives and they sound full and warm. It’s very simple, having only stereo, source, and power (which is also volume) buttons. Form factor is exceptional for a small space as well. While there are better units out there, for the price, this certainly punches above its weight.
T**R
Endgame (for now)
I dove headfirst into the hi-fi realm at the beginning of the year and not knowing what to expect. I come from a studio set up with active monitors (Adam A7) hooked up to an Audient ID44 audio interface. For my small but amazing bachelor pad, I was actually using an Echo Dot hooked up to a small pair of Presonus Eris 3.5 speakers (Don’t Laugh). Obviously knowing what good sound sounds like, I wasn’t satisfied with that set up. I started looking up amplifiers, Dacs, and bookshelf speakers. Of course people swear by AB amplifiers as better sounding, but I wanted a minimal set up that sounded good without using up too much space. Not that I don’t mind spending more cash, but I also know that you reach a point of diminishing returns. Do I really want to spend an extra thousand dollars for a 5% increase in sound quality? Not me, at least not now. So I began my research. At the beginning of the year I purchased the Aiyima A07 Pro with of course the infamous Sony SSCS5 that everybody seems to have; thank the Cheap Audioman for that. I wasn’t using a DAC, I was streaming straight from my iPhone paired up with Bluetooth. I thought OK this is cool, I can live with this. But then I started binging on more YouTube videos and soon realized that I wanted more. Sound was cool but not great. I would say that the turning point came when I found out about the WiiM Pro streamer. You wanna talk about a life-changing product, that’s it! It literally changed the game for me. From streaming from my TV, tablet, phone, everything... Chromecast, Airplay, Spotify connect, Tidal. You name it! They put all of the pieces together for me and made everything seamless. After a bit more research, I came across the SMSL SU-1 DAC everybody was raving about. As for speakers, I purchased a pair of Polk XT15 to go along with my Sony's. I liked the Sony's, but they were lacking a bit in bass and chose the Polk XT15 because they were on sale on Amazon for $135 and were also significantly smaller than my Sony's while still having a 5“ driver and a better frequency response in my opinion. The highs were crystal clear yet non-fatiguing, and the bass punchier and hefty while the Sony's sounded more boomy in comparison. Beautiful speakers all around and definitely recommend them. Of course you know I didn't stop there though! I started late night binging on YouTube and foaming at the mouth thirsting for more and better gear. Upon yet more research, I realized that everybody was swearing about the new Fosi ZA3, so on launch day, I jumped all over it and purchased it. I swapped out my Aiyima A07, turned on the Fosi ZA3 and my first impression was warmth, wideness, punch. Now don’t get me wrong, the Aiyima A07 Pro is no slouch, and it has served me well throughout the year. I’m still keeping it and putting it in the master bedroom. I love the tone controls, the Bluetooth connectivity, but the Fosi definitely had the “IT” factor. Music was immersive, I started bopping my head, tapping my feet on the ground and busting the nickel in the living room (for those that know about break dancing). I felt it was definitely an upgrade. I also like that it has balanced XLR connections which sound better than RCA and louder. Here's my setup: • Polk XT 15 Bookshelf Speakers • Fosi ZA3 Amplifier • WiiM Pro (Not the Plus) • SMSL SU-1 DAC • Audioblast Speaker Cables • Mogami 2964 RCA Cables • Gotham GAC-1 Pro SPIDF Cable Could you get a better set up? Of course! But then again, do you really need it? The diminishing returns factor kicks in really quick. I mean, It’s easy to become addicted to buying gear. FOMO is REAL! I found that out this past year. New gear is always coming out at a feverish pace, on a monthly basis it seems. but seriously, just go with what you need and sit back roll a fat one, break out the wine, crack open a cold brew and just enjoy the music! With my current rig, I dropped $600 and I’m at the point where I’m happy with my set up. It’s more than good. It’s great. Could I drop an extra thousand dollars on a better DAC and amplifier? YES. Would people notice the difference? Absolutely not! With my current set up, I get compliments all the time. The music sounds amazing, and the ladies love it. Good luck on your journey and remember, diminishing returns!
Trustpilot
3 weeks ago
3 weeks ago