Axiom Home Page Forums General Discussion Stereo FOSI ZA3 MONOBLOCKS - GOOD!

I picked up a pair of Fosi ZA3 mono blocks (sort of) after watching some VirtualHiFi Youtube videos with Janusz Sikora, the designer of the Qualio IQ speakers. He is very interesting and loves these wee amplifiers.

I put them in my workout room, with a pair of Axiom M50 like Michaura M66 very large and excellent stand mount speakers, a Pure Audio Lotus5 DAC which I connected with XLRs to the ZA3s, an old Sony NS999ES disc player hooked with a coaxial cable. The ZA3s have sub outs, so I hooked each to its own Velodyne servo subwoofer.

Wow! Big sound. Pretty analog sounding, not that digital hash most class D amps produce. Mids are pretty darn nice. 235 watts into 4ohms, in mono mode. Beefy. They come with a 48 Volt, 5 amp brick. I think I got them from Amazon for about $130 each. A Joke!! These are really good.

They can be selected for stereo mode and are rated at 155 watts per channel. Mono is not a true mono, you just flip a switch and disable one channel. This ups the output to the 235 watts in mono.

I ordered some Sparkos 3602 opamps which I will roll as soon as they arrive. Opamp swapping is a snap out and snap in operation. This is supposed to be a sound quality upgrade, although, out of the box, they sound pretty darn good!!!

Axiom speakers are pretty easy to drive, and will be no problem for these little wonders. I also tried them with a pair of Dahlquist DQM905s, about 87db efficient. No problem, and the sound is excellent!!!

I may even try them with the Wilson SabrinaXs, a truly difficult load (down to 1 ohm!) I'll report back.

If you have or want to put together a second system, or want to save on an amp so you can go for better speakers, this would be a wise choice, IMHO.

The Fosi site is running a 20% off XMas special. Cheap and good. What's not to like?

Follow up on the Fosi ZA3 monoblocs.

I've tried them with the Michaura M66s and the Dahlquist DQM905s. The 905s have a richer sound, gorgeous midrange. The M66s are very nice, a bit leaner.

What is remarkable for a pair of ~$150 amps is their true timbre, attack and decay. Folks these things are the best kind of audio joke.

The Sparkos 3602 op amps and Gregor's Polish dual op amps have arrived. Audio nuts are coming over later. We'll listen to the DQM905s and then the Harbeth 30.2 Anniversaries with the stock op amps.

Then we'll do some swapping. Should be fun.