[Robin Hood]

This is the only info I could find:

Acoustat 2+2 loudspeaker Specifications

Description: Full-range electrostatic loudspeaker.
Frequency response: 28Hz–20kHz ±2dB.
Nominal impedance: 4 ohms.
Power capability: 500W.
Maximum output: 115dB at 20' in a 16'x24' room.
Minimum power requirement: 50Wpc.
AC power consumption: 5W.
Dimensions: 94" H by 20"W by 3.5" D.
Price: $2100/pair (1984); no longer available (2012).
Manufacturer: Acoustat Corp., Fort Lauderdale, FL 33315 (1984); Rockford Fosgate, 600 South Rockford Drive, Tempe, AZ 85281 (1990s).

[glynnw]

FWIW, I drove a pair for several years with a CJ 45 watt  tube amp  and never felt a lack of power.

[Rocket_Ronny]

I had Acoustat Model 3s and drove them with a Classe DR2. 25 watts per channel, but beefy current.

I believe the 3s were around, gulp, 76 db, maybe 78. So the 2+2s might be around 80 at best. That's my guess.

They never did like to publish the eff. and I believe it was because it was so low.

Still, the 2+2s are awesome. If you can snag a good pair you should be very happy. That is the Acoustat I would go for, unless you could get the larger version, or the original direct drive 3s.

Rocket_Ronny

[TONEPUB]

Great speakers, the more power the better, and they work great with tubes or solid state.  Used to use mine with a Threshold 4000A, also had great luck with an Audio Research D-79.  Had an MV-50 but that was a little wimpy.

[TONEPUB]

Levinson 23.5 is a nice choice too if you can find a clean one with a nice tube pre...

[MrAcoustat]

The most difficult Acoustat to drive as always been the 1+1  81-82db NONE LOWER THAN THAT

[satie]

The most difficult Acoustat to drive as always been the 1+1  81-82db NONE LOWER THAN THAT

I think the 2+2 is 84-85 db, I lived with one driven by a Transnova for a few weeks.

[josh358]

A friend of mine just scored a pair of 1+1's. I'm posting this so Satie no longer has to think that his listening room is messy.