Amp for Quad ESL 57

Franks,

I drove a pair of Quad 57's with an S-30 a few years ago. Since I'm a dealer for the latter I'll refrain from editorializing too much and just say that yes, it can be done.

For stacked Quads driven in parallel, in my opinion the S-30's output impedance is too high. The M-60 would be a better choice. If the stacked Quads are wired in series, I think the S-30 would work fine.

I know a speaker cable designer who used stacked Quad 57's (wired in parallel I believe but I can find out for sure if you'd like) driven by M-60's as his reference system.

Duke

Any of the Esoteric Audio Research amps will sound marvellous with the Quads, other than being built in the same home town, the designer, Tim De Parvicini voices his amps with Quads and winds his output transformers to optimally deal with the wild loads they present.
My single ended EAR 869 profoundly pairs with the 57's as if there was to be no better of a perfect match, this combo delivers the 4th dimension AND bass !!

Thanks to you all. Lots of good suggestions.

I've heard great things about the EARs. AS for the EAR 869, are 15W x channel enough? I have a small room right now, but I plan to move to a slightly larger one soon...and I am afraid I need a bit more power.

Any of the Esoteric Audio Research amps will sound marvellous with the Quads, other than being built in the same home town, the designer, Tim De Parvicini voices his amps with Quads and winds his output transformers to optimally deal with the wild loads they present.
My single ended EAR 869 profoundly pairs with the 57's as if there was to be no better of a perfect match, this combo delivers the 4th dimension AND bass !!

Well frankly it's not how much power you throw at the 57's, which is where many go completely wrong....they can only handle so much to start with, I've tried 80wrms PP tube grunt which did not even remotely do any justice to what these remarkable speakers can impart...as previously mentioned the EAR amps are optimally suited to the Quad load, this is more important than mere watt figures will tell you.
My room is 4.5m w x 6m open ended continuing into an open plan area, the EAR 869 was more than sufficient and the bass was superb...dynamics is relatively limited on any Quads regardless of how much power you try to bludgeon them with !
Having said that, I've spoken with other owners who swear by the pairing of 57's with the EAR 861, which is a PP version of the 869, delivering twice the output power per channel.
Whatever you do, if you can have the opportunity to audition the 57's with any EAR amps, I'm sure you will be very impressed.
From personal experience I think the pairing of 57's with the right SET amp such as the 869 is one of the very rare combinations which allows you to enter the 4th dimension of sound such is the tangible palpability...I sat a friend down to listen to Jazz at the Pawn Shop and he literally stood up and looked all around for hidden speakers saying how freakily present the ambience was, as if one was sitting inside the actual venue and partaking at the bar...indeed it is profound how betwixt these two items of electronics from Huntingdon, UK, music is conjured.