Originally Posted by H22
Whew, read the whole thread. I am very interested in this amp, but need to finish up other projects at the moment.
I was wondering how this amp compares (sound wise) to a mini or mosfet max? ,I have built both and really, really like My Mosfet-Max, and wish i had not given the mini away as a gift.
just wanted to know what differences there were, if any.
The best way I can answer in terms of sound quality is my standard blurb: Beezar's prices are proportional to sound quality.
That said, I guess it depends on your definition of sound quality. The MiniMAX, IMHO, assembles into one of the nicest packages around and is a great value. The MOSFET-MAX can be built as a real power brute and has a lot of flexibility with the onboard DAC, etc. Both can be built with dead silence. As you've probably read in this thread, however, there may be a very slight hum with certain headphones using the Torpedo. I think we've gotten that down to no more than a nuisance and it's completely inaudible when the signal is amplified, even with those phones that can pick it up.
Basically, you may notice that the Torpedo's bass is not as strong and punchy as the hybrid amps above, but the mids and highs are to die for. There is no lack of detail whatsoever, but at the same time - harshness simply doesn't exist with this amp. In particular, connect any Grado to this amp and you will never experience harshness, yet the detail and transients come through - same for HD600's as well. As for the rest of the sound quality, I believe I stated this earlier in the thread - there's an airiness imparted that seems to define a real soundstage relative to hybrid and SS amps. Some people would say that's simply the "friendly" even-order harmonic distortion that pure tube amps seem to present. To the extent that the Torpedo is a "real" tube amp*, maybe that's true - I don't know.
What I do know is that Dsavitsk has designed a true, transformer output coupled tube amplifier all based on a PCB. There is no wiring at all, except for a small safety ground wire from the PCB to the case and the ubiquitous ground wire for the Alps RK27 volume pot. There is no turn-on or turn-off thump whatsoever, gain is perfect (middle of the dial or slightly less for almost every headphone I own), and low impedance phones (Grados especially!) are outstandingly driven. (High-impedance affinity is already expected with a high-voltage tube amp). To add to all of that, the tubes are extremely plentiful, extremely varied, and dirt-cheap - I mean, REALLY dirt-cheap. If you are willing to buy in volume (several hundred), you can get them for a dollar or less! With some of the bigger tube dealers, they may number into the tens of thousands.
Anyway - hope that helps!
* Some may take issue with all the "sand" devices in the amp, but those are common in many "real" tube amps, yet perhaps unique in their implementation by Dsavitsk - CCS, rectifiers, biasing circuit. The essence of the pure signal input-to-the-tube and transformer-coupled output is not corrupted.
Edited by tomb - 2/2/13 at 6:45am