Acoustat , Hafler TNT and Jim Strickland


I own Acoustat 2+2 speakers and right now powering them with a Panny XR55 receiver (dual amped) (not the ideal I know).

I know the Acoustat TNT amps are the best match but since they are tough to find, wanted to get which Hafler TNT amp's are also great (think Strickland moved to Hafler and did their TNT series) and also are there other amp's designed by STrickland that would work well.

Side question, what is it (technically) that makes the Acoustat amp's work well with Acoustat speakers, asking as if I can identify the characteristic can look for the same characteristics on other amp's.


The TNT amps work, but I wouldn't say are the definitive choice. You can also use Acoustat direct drive tube amps (Acoustat X et al.) with the speakers, bypassing the transformer system altogether, although the amps aren't that common and the 6HB5 output tubes are getting to be hard to come by.
I've used tube amps on my Model III's as well as solid state. The tube amps were magical. Solid state was amazing but tubes on those babies...whoa!

In fact, I found my Audio Research VT100mkII w/ ARC Ref-1 pre was better than my Acoustat Monitor IV's with their servo tube amps and the same Ref-1 pre.
I have Model 3's also. Although they're now packed away, I did listen to them for over two years. They had been powered by Haflers, Rotels, Acoustat TNT, and finally a Threshold T200 amplifier. Nothing touched the T200. It made the biggest difference in all the good ways. The TNT was just too "edgy".
I have an Acoustat TNT-200 and a Hafler 9505. Both do very well driving my Acoustat 2+2's.

The Accoustat and the Transnova from Hafler are the same design. They are designed to  take advantage of the advantages of Mosfets ability to self stabilize at high temperature. Other amps use the mosfets in topologies designed for earlier bipolar devices. So the transnova can gets most of gain in the final stage, and have less gain stages, only 3 a la Nelson Pass.  Most amps have 5 or so gain stages, the Transnova has 3. This also allows the input state FET to run in class A. FETs have characteristic gain similar to tube amps. This allows the amp to be very stable into terrible loads like one or two ohms which would send other amps up in smoke. It's a patented design. The other amps which are very stable into difficult loads are the new digital amps, or the NAD soft clipping amps   I use this amp to drive Quad 989's and have plans to use also for Original Ohm Walsh Driver, notorious for blowing up. I bought an old pair on Craigslist that needs reconeing. The other thing in general is you dont' want to run amps so hard, you get tons of distortion. 35-50% of rated volume keeps most amps and preamps in a very nice low distortion mode, which is what makes them sweet. I keep hearing how you have to have at least 250 watts per channel or bi amp, that's all a load of rubbish, no offense.