Fosi Audio 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.

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.

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.

Zakupiony do współpracy z Wiim Ultra, spisuje się doskonale. Opcja trigger działa idealnie, wzmacniacz włącza się razem ze stramerem. Bardzo dobra jakość dźwięku. Bez problemu napędza kolumny zarówno podstawkowe jak i podłogowe. Szczerze polecam!

A critical part of what is becoming a very beautiful sounding system. I have an older set of kliptsch tower speakers and sub. This amp(s) drives sound that is clean and true. I have since purchased another ZA3 and am driving them in mono mode. Very good quality Very user friendly Very highly recommended

where to begin! My previous setup was Marantz PM6007 with WiiM Ultra & Elipson Planet L Speakers. I was ok with the setup but I knew, was missing something on the higher frequencies & details. just heard about this product on youtube channel "VirtualHiFi" - found many good videos with sound test comparing with 10k - 15k USD costing amps. I took the decision & bought this today with 48V power supply & right now its been playing for 3 hours replacing the marantz PM6007 only with rest of the same setup. I have no words to say - Man! it's blown away the marantz right out of the box and my elipson planet L speakers have come to life. it's a night & day difference. I kept the volume at 75% position & controlling the volume from wiim ultra and it's running cooler now than at 100% position. i am seriously thinking about the reason why it is sounding great than the marantz. Hmm.. may be one reason - the frequency range with 0.1+-DB? I don't know but it's sounding fuller, detailed, airy high-frequencies & analogue kind of texture. ZA3 changed my mind to join in the class D era as I have ordered another now to try as Monoblocks. I am totally happy & the value for money is top of the roof! I really appreciate the FOSI TEAM behind this to design such a great product! Best of luck for your next musical invention!!! Got the second one & set them as monoblocks - sound stage is wider now & details are more cleaner especially the vocals & mid range. I started enjoying my setup now with peace of mind!

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.