Power requirements for Acoustat 2+2s

I used to own Acoustat 3's with the c mods and drove them fine with a Hafler 220, which if I remember was 100 watts per channel. The Hafler wasn't a great amp IMHO but it drove the stats to any level I desired.

I successfully ran a pair of 2+2s with Blue Medallion transformers with a pair of VTL Tiny Triodes ( newer version with 45 wpc in tetrode mode). Not too loud but up to the power limit, the sound was AMAZING. The TT 25s have a super deep stage and are very transparent. The MB 150s should have no issues with the 2+2s as long as you are not looking to have them at huge volume and dynamic swings. I am assuming the 150 monos are running either KT-90s or EL 34s? The later versions ( MB 175s) run the 6550c and will have an advantage in "PRAT" but not be a sweet in the mids.

Sweet speakers. I used to drive 2+2 medallions with ARC VTM200 monoblocks (6 6550C's / amp). They did the trick, sounded very good, but certainly were not overkill. It may come down to your room size and desired listening levels.

I had good results driving a pair of Acoustat 3 medallian mods with a Conrad Johnson MV75A-1---75 watts-6550 tubes.

Where I wasn't so lucky was trying to drive Martin Logan CLS11z with a 75 watt VTL tube amp.

The best sound you will ever get from any of the old Acoustats is to find the old tubed servo amps(nothing like conventional tube amps)and wire them up.

I have several friends who still run 4, 3 Panel Acoustats with the servo amps, and one has the Acoustat 2+2.

I have yet to hear any Acoustat sound as good as the servo amp powered versions.

I have 2+2's and can tell you from experience that many amps can drive them without blowing up or sounding obviously wanting in any department. However, until you have tried several amps in rapid succession you won't appreciate how different each sounds, and therein lies the challenge.

I ran my 2+2 on the following: Macintosh MC7300, Acoustat TNT-200 (stock and later modded), Hafler 9505, and PS Audio HCA-2.

Each sounded great and could reach ear-splitting levels without breaking a sweat. But until I tried the TNT-200 I had no idea my Mac wasn't doing the bass region of the 2+2's justice. The TNT-200 had bass slam; the Mac didn't. The 9505 was even better in that department.

But I finally found contentment with the PS Audio HCA-2. It simply does everything well while being completely silent and cool.. the amp you just forget is there. I think if these class D amps had been around in the early 1980's when Acoustats hit the market they would have been a natural match. 25 years too late..!