Fosi Audio ZA3 Balanced Stereo Amplifier Home Audio Component Mini 2 Channel Mono Amp TPA3255 for Subwoofer Desktop Home Theater Bookshelf Tower Floorstanding Passive Speakers with 48V Power Supply

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.

After already using the device on stereo with Fosi's Bluetooth DAC and P3 preamp, I am now using two ZA3s on my Klipsch RP600 biamplified (separate whoofer and tweeter), and a powered 100W subwoofer and the sound that was already great became magnific! The HiDef sound from my computer goes through the DAC to receive the warmth of the P3 tubes, then gets amplified with tons of headroom into my RP600 delivering a highly impressive soundstage and crispy clarity and depth to the sounds. I am hearing details that were only noise before. Even on extremely low volumes at night, the level of detail is very impressive. Highly recommend to any one who wants to enter into HiDef and wants to buy quality, easy to install, and use devices while not breaking the bank! I just wish it came with the 10a power supply

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.

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!

Great little Chi-Fi amp. Plenty of power for a desktop system or a system for a small room. I am running this with their ZH3 DAC\headphone amp, The only complaint I have, which is very petty, is it would have cost them a few cents to include a trigger cable, other than that, it works well, I did replace the Opamps with some high end Virtual HiFi Supersonic V2's which makes this amp sound amazing.

nice little amplifier; amazing price; super compact; blue tooth connectivity is great

First, let me say how impressed I am with the ZA3. It packs a huge punch for its size. I own a pair of PSB Stratus Gold i speakers, which are known to be difficult to drive. I bought a Yamaha A-S701 and the Fosi ZA3 just to compare the best I could get for the price in a Class AB and a Class D amp. I ultimately returned the Fosi just due to the amount of extra cables I needed in my particular setup vs the Yamaha 701. I would 100% recommend the Fosi though as it gave me 85% of the performance of the 701 for a small fraction of the price. The Yamaha and Fosi sound about the same TBH. The Fosi also barely gets warm at higher volumes where the Yamaha definitely gets toastier. The Fosi is clear at all volumes with no distortion that I noticed. About my only complaint with the Fosi is that you have to hold down the volume knob to turn it off and on. I would much rather they move the stereo/mono switch underneath and make that the power switch. Do not hesitate to get the Fosi if you are looking for a reasonably priced amp that performs very well. I think a perfect setup would be to have another brand preamp that has 12v trigger connected to this so it would turn on and off with the preamp, but also have a lot more options for inputs. I do have a lot of sources so that factored into my decision. This is a great amp you won't be disappointed with.

I had gotten two of these as a replacement for bulky stereo AB amplifiers that I wanted to part ways with because of heat, noise, and physical size in my setup. I appreciated the initial build quality, but within the first few minutes of use the main volume knob was becoming an issue with how little resistance it gives to adjustment. With an accidental bump or pets around, the volume could accidentally be brought to max in less than a second, which is concerning for the speakers that I have connected. Unfortunately my setup is rather hodge-podge, with a mixture of refurbished studio equipment and homemade solutions- notably two speakers that are well within the spec of the amp, proved very difficult to drive and has often tripped the internal protection, which will disable one speaker, not consistently but at random. While the confidence in my own construction is low, I didn't find myself relying on these amps to be a constant variable in diagnosis, given the sudden speaker drop-outs without any kind of indication on the unit. I had ended up switching back to my old amplifier for the meantime, considering it has never dropped audio, even with my wack configuration. One thing that I do appreciate about the design is the different inputs as I ended up using the balanced TRS ports through my audio interface, which was not a common feature to find with other options near this price point. I also did not have any issues with the sound they put out, even through my panel speakers which are very sensitive to amplifier noise. My recommendation would be to curb expectations for the level of output these can deliver. It varies significantly speaker to speaker but they can be very easy to trip and need to power cycle. The form factor can be great for desktops but be wary of the enormous brick of a power adapter that it comes with.

I purchased the za3 to power a pair of surround speakers in my HT rig. To test the za3, I connected it to a pair of older Polk RTiA1, Anthem avm70, and Sony SACD player. I chose Rickie Lee Jones Pirates SCAD to demo the Fosi. The sound was very impressive from the start and only got better as the amp continued to play. It barely got warm and the speakers were completely quiet when no source material playing and the Fosi volume set to max. Impressive! I connected the Fosi to surrounds, re-ran the sound calibration, and, again, the Fosi did not disappoint. This little amp proves that spending big dollars isn't always needed. The Fosi has a 12 volt trigger. Sadly, I did not have mono cable on hand with a male 3.5 mm connector on each end. The cable I had was stereo with 3.5 mm male on one end and 2.5 mm male on the other. Through a bit of simple improvisation, I spliced the 3.5 mm connector to a 12 volt DC power adapter, connected both the Fosi and power adapter to the same power bar. Now, turning on the power bar powers on the Fosi.

Excellent amp! Lots of power! Greeat sound quality! I love the styling, and even like the volume button being the on off switch, it makes a lovely noise when you turn it off lol... Mine came with a 48v 5a psu, couldnt be happier with this purchase, seems great value!

48v 5A adaptörü takıp kendi dahili dac.ı rca ile denedim evet ilgi çekiciydi fakat standart bi d -classtı. Daha sonra 3 adet muses02 opamp sipariş verdim ve elime ulaşıncaya kadar amfinin yanmasını bekledim. Nihayet geldi opampları değiştirdim ve sub opampı devre dışı bıraktım(kullanmadığım için) vee Xlr (cardas golden cross) ları bağlayınca vaaay müthiş ses!! Birçok pahalı amfiyi sınıfta bırakır çok net!! Opamp yükseltmesi yapıp güzel bir Xlr ile kullanınız şaşırcaksınız....

Klinkt echt prima. Aanrader. Werd ook tijdens een hittegolf nauwelijks warm.

These small class D amps are exceptional value for money! I have amps that cost 20 times more than the ZA3 but does not deliver even 5 times the performance. I tried this (just for fun) with my power hungry Sonus Faber Sonnetto I bookshelves and it managed to make them sing beautifully up to the max volumes I listen to (70-80 db). I use two of them in mono mode to power my desktop speakers mainly for nearfield listening. The only thing I miss is a high low pass filter for the sub output. This is honestly exceptionally priced HiFi! The performance makes the price a steal! And I am so inclined to build an entire system of Fosi products just to compare its performance to price against my other ridiculously priced higher mid-range systems, which I 'm sure this will give a run for the money! I heard some premium and expensive high-end amps, and this definitely does not compete with them (I mean, come on if you're expecting this!), but for mid-range and other entry level products, I believe this thing is a certified LGK!