Pre-amp suggestions for Thiel 2.4/Pass Labs XA30.5

"without good solid bass response the Thiels can sound a bit tipped up." Explains a lot of the stereotype, but also what some swear by Theil as among the best speakers ever made - got to have the right amp:)

The Atma-sphere MP3 would match up very well with the XA30.5, although it also worked very well single-ended with the Joule LA-150 MKII and Signature edition, both of which can be set to a lower output impedance. If the 2.4 is anything like the 2.3 and 3.6s I think the combination of the rich tones of the Joule would do wonders with a speaker as neutral as the Thiel, a little warmth would not be a bad thing. The combo sounded pretty darn good with my Merlin VSMs which are also not particularly forgiving speakers. You would not have suckage with either the Atma-sphere or Joule preamp mated to your Pass amp.

Cmalak, all part of the learning process for OP, and sometimes you just have to hear things for yourself to know for sure. The XA30.5 is a magical amp, but not magic, the Thiels simply need more power to play their best. It is a conondrum, I often consider 20-30 watts Class A amps since I think they sound great with the right loads (Luxman for example)but I always fear I'm forcing the power issue and I should know better, even on my easy to drive and relatively sensitive Merlins. If I owned Maggies or Thiels, I simply would not consider driving them with the undoubtedly wonderful Pass XA30.5 and other "low" wattage SS amps, as much as I would like to since those amps sound so darn good at their power rating - but for those speakers give me a 200 watt MAC!

Owned the Aleph 3, 2, and J - and loved them, but I would describe them as amps that do best with speakers that are tube friendly - highish and smooth impedance - non are real current monsters, which is what I think a speaker like the Thiels or Maggies need.

Just out of curiosity, does anyone know what amplifiers Theil has used at shows the past 5 - 10 years? Likely a good match. I actually heard 3.6s with ARC VT100s a few years back and that sounded pretty darn good, so even a well designed tube amp with enough power should work.

Yup, there is that side of it too:)

I bet the Belles MB-200 Monoblocks up for sale right now would drive the heck out of them.

Yes, I was mighty impressed with the ARC VT100, and I assume the Ref 110 would be better yet. ARC seems to also work well with Maggies - so difficult loads and tube amps that do seem to work well. I have never heard the combination, nor heard others comment on it, but it would seem the that the stereotypical sonic flavors of Thiel and MAC (6600 integrated would do) would make for a pretty good combination - detailed neutrality with smoothness, power and autoformers for handling impedance swings. Again, never tried it, but would be curious.

I thought the point of the autoformer was to provide the same watts into any load from a give tap? Load tolerant?

"but I thought the use of autoformers prevented doubling down into halve impedance's?"

That what I thought, the point being that you would get more linear/constant power output throughout the bandwidth without variances caused by impedance swings.

Al, do you think that McIntosh is on too something that other SS folks are not addressing? Obviously they have been doing this for a long time - is it a difference that makes a difference and all towards the positive, or a just a tradeoff like so many other things in audio design?