ZA3 Balanced Stereo/Mono Amplifier HiFi with TPA3255 Chips, Mini Audio Amp Monoblock with XLR RCA Inputs and 12V Trigger-in for Desktop Bookshelf Passive Speakers with 48V5A Power Supply

So...in my opinion...this is were Class D now defeats Class A-B amplifiers. I have these with the ZD3 - running in mono. The installed NE5532 op amps in the ZA3's are ok but after doing research I found the best op amps that are inexpensive. The LM 4562 Op Amps...provide stunning clarity and resolution. Even without this modification..the ZA3 is a truly innovative product. The ZA3 has dual amplification chips...not a single unit. This provides the greater resolution and fidelity. The ZD3 already has these installed and the resolution is superb. Don't forget the ZA3 has balanced XLR inputs..which is class leading in terms of inputs. In such a small unit ! The sound is so refined and detailed. Buy yourself a power supply filter for your wall sockets and some ferrite cores and this further improves detail for any sound system. I did buy a second ZA3 - added the LM 4562's of which 3 are required for left - right & XLR input. 5 - if you have a subwoofer. The 12v trigger is so convenient...just by a good length 3.5 jack splitter cable to control both ZA3's with the remote. So I purchased the extra ZA3 and upgraded to mono. Each dual amp chip in each ZA3 - now controls one speaker - providing greater power and detail. I'd say it has boosted speaker detail and power delivery by 40%. What's interesting is that this isn't just about volume/gain...it increases depth and detail greatly. Is it necessary? No. Other amps in Class D - have only one amplifier chip and can't match the resolution of the ZA3. What's interesting...if you check vastly more expensive amps - check what op amps they are using. Very often it is the standard NE 5532's or OPA. The LM 4562 chips are sort of a hidden gem in op amps...fast and detailed and the fosi ZA3 is hardware compatible with their greater resolution and depth. It's only £10 for two chips...but make sure they are genuine. I have wharfdale 9.1 diamond speakers...and for the first time..I modded the crossover to film foil capacitors which I didn't think I would be capable of doing. Just takes a little time and I have never soldered before...but I gave it a go and it improved the quality of output greatly. The ZA3 is a power efficent and small device with just about everything you'd want for a high end audio system. I think it is a genius product that is vastly underrated. Even prestigious audiophiles are using the ZA3 in mono configuration.

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!

Very smart little device which I combined with a Fosi pre-amp. Surprisingly powerful with good quality sound. Looks v cool.

Second edit: Fosi Audio saw my message below and has contacted me to offer a free replacement without me having to ship the other one back. Really good customer service. Warning: Everything I wrote below is true, but now I'm having scratchy noises while adjusting volume, just like an elderly amp with an analogue pot. Not sure how to get it fixed without shipping to China. Extremely disappointed. I got one of the first batch of these, so I've had it now since December. From the moment I hooked it up to my desktop system (usb out from computer, Dragonfly Red as a dac, Q Acoustics 3020s, REL TZero subwoofer) I was blown away. It has a rich, natural sound that reminded me very much of old Class A analogue, but cleaner. Notes have body and weight and presence, and it throws up a big soundstage with very precise placement of instruments and vocalists. I can easily say it sounds better than amps I might have spent over £1,000 on 10 years ago. There are a couple of annoying things about it, however. I'm not fond of using a volume knob as a power switch, and I hate having the stereo/mono switch in a place it could accidentally be knocked, though that's never happened in my case. (It seems a lot of people are really enamoured with the idea of using two of these as monoblocks, but I don't have that kind of power requirements.) Honestly, it's hard to imagine being able to use more power than it already has with the 48v brick unless you live in a detached house and have a very large listening room or very hard-to-drive speakers. This is a fantastic little bit of kit, and I've had a few through the door as I was working out which I liked best (Marantz PM6007, Aiyima D03 and A07, SMSL AO200 MKII, Topping PA5 II). None of them could quite match it. The Topping comes very, very close and would easily be my second choice because it's so beautifully clean and doesn't put a foot wrong. I just think I like a slightly meatier amp with a touch of warmth, and that's the ZA3. If you're after a less warm sound or if your speakers are really lacking in high end, I might go with the Topping, which also deserves a lot of praise. I listen to it every day, and I'm still shaking my head at how something so cheap could sound so good. I'm not sure if this is a sign I've been exposed to too much audiophile snake oil over the years or if the quality and implementation of Class D amps has just come astonishgly far in that time. I'll also add that the build quality is great, and it looks extremely nice in person.

Fosi Audio's best amp in my book, especially when paired with the ZD3 as I have it for my desk top system. Superb value for the money, I still can't believe how cheap it was and still is. The amp drives every speaker I have with absolute ease!! Great sound stage as well. Just a fantastic bit of kit as they say, TOP MARKS Fosi A Further UPDATE, as I have now purchased a second ZA3, I've been so impressed with the first one in 'Stereo', I thought it would be rude not try the ZA3's in 'Mono' so required a second ZA3. Boy oh boy, this set up is just fantastic, the sources are CD via coaxial, Laptop via USB, mobile phone via B/T for streaming. All three through the ZD3, acting as DAC & Preamp, with the ZA3's working in 'Mono'. I can't believe how much better everything sounds, more defined instrumentation, cleaner sounding mid range and treble, with a more powerful bass punch, with an even wider soundstage. Absolutely amazing, completely blown away, and I'd say this little set-up, drives my floor standing speakers just as well as my Cambridge Audio CXA81 MkII integrated amp does, for half the price. Now contemplating on the purchase of the ZP3 to act as pre-amp, with the ZD3 as DAC only, so I can incorporate my T/T into this 'little' combo.

These are an amazing amp for the money. There’s plenty of reviews on YouTube comparing them to £7000 amps they are that good. Brilliant as a stereo amp and even better as a pair set in mono connected via xlr. Great paired up the pre amp ZD3 if you’ve using a streamer or CD player as source. Ignore the audiophile snobs and the lack of reviews on sites like what hi-fi that depend on pushing big names to fund their site. What’s even better is you can crack these amps open and swap out the opamp chips for even better performance. There’s so much power in these that you could easily power big 100w speakers as well as 30W book shelf speakers. Sleek and clean look small in size so two fit nicely side by side. Easy to connect put blistering performance for the money. Only sight negative if used in mono it lowers the subwoofer volume . So you may need to up the gain to compensate.

Excellent. Originally used with a q6 dac feed via USB from a laptop and p4 preamp to a pair of wharfdale lintons. Swapped q6 and p4 for a topping velvet and the difference is tremendous. The za3 easily powers my wharfdales way beyond volumes I would need to get myself evicted. No hum , no noise whatsoever and great clarity and seperation. Incredibly clear. Now fed with the topping I have a stunning system

After much thought, I purchased two of these Amps to work in conjunction with the Fosi DAC ZD3 that I had previously purchased. I have both Amps set up in Mono to the DAC. The DAC does the channel separation. I have not lived with the system for very long, but initial impressions are that these are incredibly good amplifiers that really punch out good clear sound. They are also now possibly exposing the weakness of my speakers, but that could also be just another head rouse to purchase a different set of speakers. I like the fact that I can later play around with Op Amps, and that will take my Hi-Fi hobby into another dimension. I did have a little trouble setting up the triggers to both Amps, but that was easily overcome by purchasing a 3.5mm male jack headphone splitter that goes into two 3.5mm female ends. I have then added two short 3.5mm male to male cables to go from the DAC (now doubled) trigger to the amps. It works perfectly and the trigger does not seem to mind a double (stereo) 3.5mm lead for it to work. CEC works brilliantly on the DAC, so I can now turn on the whole set up from my smart television. The television is hooked up to the DAC via eArc HDMI, so a digital signal is received at the Fosi DAC, which is in turn doing all the heavy lifting to convert sound to an analogue signal, which it passes to the Amps. The Amps are turned on by the 12v triggers rather than the CEC signal.

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

He comprado 2 unidades del Fosi ZA3 para usarlos en Monoblock (mono) uno a cada una de las cajas que tengo JBL. Espectacular siendo un amplificador bastante económico la potencia que entrega. No altera el sonido y reproduce exactamente la calidad de las 2 fuentes que les he conectado, la interfaz de audio Focusrite por el RCA y una Denon Prime Go+ por su XLR. No se aprecio distorsión alguna y el balance es bueno. Muy contento. La fuente es voluminosa de 48V y con un solo amplificador en estéreo seguro que irá también como un cañón en rendimiento aunque no lo he probado todavía. Me hubiera gustado un interruptor para el ON/OFF fuera del mando de volumen, pero vamos.

Ho acquistato il Fosi Audio ZA3 con l'alimentatore potenziato da 48V per completare il mio impianto Hi-Fi da scrivania a componenti separati, e devo dire che il risultato finale è andato ben oltre le mie aspettative. Il mio Setup attuale: L'amplificatore è l'ultimo tassello di una catena interamente collegata sul mio PC desktop: * DAC: Fosi Audio ZD3 (collegato via USB con driver ASIO bit-perfect su Qobuz) * Preamplificatore / Amp Cuffie: Fosi Audio ZH3 (unito al DAC via RCA e collegato allo ZA3 tramite cavi XLR bilanciati) * Finale di Potenza: Fosi Audio ZA3 (questo modello, impostato in modalità STEREO) * Diffusori: Coppia di Klipsch R-41M + Subwoofer attivo Yamaha NS-SW100BL (collegato all'uscita SUB OUT dello ZA3) Prestazioni acustiche e potenza: In modalità Stereo (alimentato a 48V), lo ZA3 è un vero e proprio mostro di potenza. Ha una riserva di dinamica enorme. Pilota le mie Klipsch R-41M (che hanno una sensibilità di 90 dB) con una disinvoltura disarmante. Il suono è incredibilmente vivo, arioso e trasparente sulle medie e alte frequenze, tipiche delle trombe Klipsch. L'uscita dedicata per il subwoofer funziona a meraviglia: lo ZA3 gestisce i diffusori principali mentre il mio sub Yamaha copre le frequenze ultra-basse dal pavimento, creando un palcoscenico sonoro tridimensionale pazzesco per essere su una scrivania. Comodissima la presenza del trigger 12V: ho collegato i tre dispositivi a cascata e con un solo click sul telecomando dello ZD3 si accende l'intera torre simultaneamente e in totale silenzio (senza alcun "pop" o "bump" nelle casse). Conclusioni: Se cercate un finale di potenza compatto, dal design fantastico (che si sposa benissimo con gli altri componenti Fosi), dotato di ingressi XLR bilanciati veri e con una qualità sonora che rivaleggia con amplificatori tradizionali dal costo triplo, lo ZA3 è un best-buy assoluto. Consigliatissimo!

This little Amp surprised me beyond my wildest dreams. I thought about buying this Fosi amp for several months thinking. Theres no way this little Amp well do all the things they claim it well. Well I've had this little Amp for only a week but the music quality coming through my 40 year old speakers is beyond awesome. It's like whoever your listening to are sitting in the room with you. Don't overthink it buy this little at this price and it well change your music listening. A+

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....