Any of my existing amps work on Quad ESL-57's


Hi All,

I just purchased a pair of ESL-57's and will be keeping my eyes open or suitable amps. I'm not sure whether what I have in house are suitable.

Currently working, I've got a super high power solid state Classe Omega and a 300b SET amp made by Quicksilver Audio. For the Omegas, besides the impedence mismatch that hampers some solid state amps, do I need to be worried about too much power? If I'm careful not to blast them, should these be OK? Per the 300b's - is this too little power? Risk of clipping? The room is 14x18x11high.

I have a pair of EL34 amps: Cary SL70's - but they need some tuning up. Seems like they could be a good match. I may send these to Cary for tuneup. Any thoughts?

Finally, I have a CAT SL2, but I want to replace the fuse resistors in it prior to using it. It's an older production model, and the newer fuse resistors are safer.

If neither of my currently working amps are recommended, I may purchase an inexpensive amp to keep me going. A Rogue Atlas Magnum, a rebuilt ST-70, maybe look around for Heathkit UA-1's or other not too expensive solutions.

Good advice appreciated. Thanks, Peter
peter_s
Russell and Terry - thanks for you good input. I've read that the Rogue is a good match, so I'll wait until one shows up. The speakers do have the snubbers installed on them. In fact, the previous owner did push them too hard and stressed the diodes on one snubber, causing distortion in that speaker. He got a replacement snubber from WP and all was restored to normal.

It sounds like as long as I'm careful, I will be fine with what I have. The Cary may be an excellent fit too.

Best, Peter
Hi
I've had plenty of 57's including stacked. Best amp was the 8417 Quicksilvers.
Do NOT use high powered transistor amps - you are asking for trouble.
For solid state the old Electrocompaniet 25 watts pure class A was excellent.
So I would recommend any medium powered valve amp around 60 watts. Of what you have the Carey sounds most promising. I would try and pick up a pair of EL34 based Quicksilvers.
If you lift them off the floor ( I used small tables about 14" high ) and tilt the speakers so they are more upright, the imaging and bottom end improves significantly.
"Do NOT use high powered transistor amps - you are asking for trouble."

The ASR Emitter is known as an excellent match for PK-restored 57s. (With, of course, the clamp boards.) Considered the very best match by some gentlemen out east who have spent months or years auditioning dozens of amps of all types on them.

Of course, this is a matter of taste as always.

The Emitter is indeed a great match, but I have found that OTL tubes in the 20-30 watt range are also superb and really do give all the speaker is capable of in terms of dynamics. Which is actually quite a lot - the PK-restored Quads being around 90 dB/W. There is a Graaf GM20 for sale here now - unfortunately from Asia, though, so risky shipping perhaps. That is a fine amplifier.

Tranformer-couple tube amps of course can be great as well and most people do find 20-40 watts to be enough power (in a high-quality amp with stiff PS, anyway). But, OTL architecture seems to be tailor-made for the Quads' rather peculiar impedance.