Need Help with Acoustat Model 4 speakers

Newbee, On the contrary, your experience is invaluable to the OP and anyone else thinking of buying vintage electrstatic speakers.

I have owned 3 pairs of Acoustat 3's, one pair of 4's, 2 pairs of Model 33's, one pair of Model 3300's. The Acoustats were a 4 ohm speaker that would dip to 2ohms around 14k hertz. No problem. If unplugged, of course there will be no sound output. If unplugged for a few days, they need to be powered on (capacitors charged) at least one full day before they reach their sonic potential (good sound). Of course they will play after charging one hour, just don't expect great sound. I drive them with PASS Labs X250.5 amp (250wpc 8 ohms, 500wpc 4 ohms.

I drive a completely refurbished pair of Spectra 44 with a Coda 100 watts class A amp. High current at 50 A up to peaks of 100 A.

All the electronics are new with V caps, caddock resistors and the rest. The panels have been soaked to remove all particles accumulated over the years.

And they play beautifully, lots of impact at medium level. So the most evident question is : are your interfaces and panels top notch in full potential condition ?

Skykomish, I used to own Model 3's with the 121 c interfaces. As others have said, the speakers need to be plugged in all the time. Acoustats are fairly difficult to drive, although a 50watt tube amp should do the trick. One other thing about these speakers is that they could be damaged by arcing, like most stats. I had a friend with 4's who managed to arc them severely and that was as they say that..:0(
After about ten years with the 3's, I gave up on them and now I never look back.

Guys:
I just bought a pair of Model 1 +1 with the Hafler Medallion 141C transformers. Like the OP, I could only get faint volume out of 'em, even with a very good 150w amp. (I did plug them in). I opened the transformers up, and the fuses all appeared intact. The guy I bought 'em from, who appears honorable, claims they worked perfectly, but hadn't been used for several months. Being largely moronic about electronics, could it be something as basic as the capacitators needing charging? Your help is most appreciated.
Clueless in Chicago