HPA-nxV200 Stereo Amplifier

Hi Anthony!

After building my new power amp, I would like to give you a short description of the unit itself. Due to the fact that these amp modules are so incredibly small, I decided to go for a rather small amp. So I was able to go for a smaller transformer, less smoothing capacitance, smaller heatsinks and, of course, a smaller enclosure. I used a fully encapsulated 250VA toroid transfomer with 2x24V secondaries, a 15A/200V bridge rectifier, 4x 10.000uF/50V Panasonic TS-HA caps and two heatsinks with 1,7k/W each. The enclosure is a very rigid steel case of Monacor International.
I decided to build the amp without any input coupling caps at all, because I like to do some "cap rolling", and this way it will be possible to change the caps whenever I want to. At the moment the best I have to hands are some Black Gate N 4,7/50, 2x2 of them in super-e configuration. Sounds almost like no cap at all.

The result is an amplifier, which is, after about one week of burn in, able to deliver a very wide soundstage, a powerful, controlled and well articulated low frequency range, smooth and liquid mids and very detailed but never fatiguing highs. But much more important, this amp has a very own but yet very natural sound signature. It really shows me something about my source equipment, but remains playing everything in a very musical manner. I think this is an outstanding product. It has its own signature, not trying to copy any other amp, and it plays just tuneful, full-bodied and convincing. I really searched for some drawbacks here, but wasn't able to find any!

My reference for comparison are some Rotel integrated amps (RA-935, RA-931mkII) and some Naim Audio power amps (NAP 140 and NAP 160). My speakers are some MM Serie Master by Reference 3a, an early version of the current model MM de Capo i.

Thanks for offering such a great product to the diy-oriented!


Kind regards!
Martin Balszuweit