Class A SS vs. Class A/B SS

The '30 watt' Pass 30.5 is available in form of an integrated...the INT-30 and really puts out closer to 100 watts by 1% distortion. By than it is firmly in A/B.

So, if you can 'make do' with 30 'a' watts, the Pass may work
The INT-150 is an A/B design which is near 200 watts and about 300@4ohms.
I'd without hesitation have the INT-150 for my panels......and be willing to try the 30........

I'm running my rig with an ATC SIA2 150. The first 80 watts are in clas A then will move to class A/B for the rest. I moved from tubes (300b SET) to this simple, great sounding, staight forward integrated.
Good luck

I ran Monarchy SM-70 monoblocks for a number of years with great success. They deliver Class A sweetness in spades and drove with authority every speaker I threw at them. They were a bit noisy but the newer Mk IIs are supposed to be significantly quieter. Definitely worth a listen.

David

I own the INT-30A, have not heard the INT-150. Mark at Reno HiFi strongly recommended the 30A for my comparatively quiet listening habits, and I've been very pleased. But I assume Pass makes both models for a reason, and each involves a distinct set of compromises (see the detailed review of each in 6moons). In particular, it wouldn't surprise me if people with large rooms, thirsty speakers, and high volumes had "power issues" with the 30A. Here's a little test I did (from another thread):

"Just compared my new INT-30A (basically the 30.5 boxed with a minimalist pre) against the INT-30A pre-section running an Odyssey Dual Mono (180wpc) as amp. Speakers are 92/4, room 14x20 in an open plan. Obviously, "synergy" favors the INT running as intended, and it did sound conspicuously better than the combo with the Odyssey: more air, richness, texture, detail, etc. *Except* that the combo had conspicuously more authority on the lows. I listen to mostly "small" music at lower volumes, and I'm sold on the sweetness of the Pass, but I concluded that those who say many listeners will want more power than the 30 are likely on to something."

At present I'm very happy with my decision, but I doubt the difference between the 150 and 30A (or the corresponding separates) is a coin flip.

Enjoying the simplicity of an integrated, btw.

John

If you are going to go with Pass Labs, I would definately go with their Class A amps, like the newer 30.5 vs. their Class A-A/B amps.

My experience with Pass amps is that they are great as long as you stay in class A, but once you cross over into A/B, you suffer.

I would not rule out the Pass Labs Aleph amps (which operate only in class A) as well. The Alephs are SET based solid state amps. If the power they provide will be sufficient for your needs, you may very well find them quite enjoyable.

Also, I think a Mark Levinson amp may deliver both a sound you may like and enjoy. Even an older 23.5 or a 27/27.5 (which I believe is only 50 wpc) would also be considerations - of course used.

Assuming your 50 watt KT88s is plenty for the Adagios, I think you have some good options.

Finally, my experience is not that watts are watts. Oh, if it were only so easy.