I sure miss my Quad ‘57s!

Hard to live without ESL's when you've owned them. And yes very unfriendly to amps that had a go at driving them properly. Naim amps would blow as soon as they saw them, they just had to be in the same room, not even wired up!!!😉

Cheers George  

I built a poor mans HQD back in the day, have a pair of the 63 when that itch needs a scratch and a 303 amp ( along w others )

fun

@mglik, if you decide to try the ESL again, give Kent at Electrostatic Solutions in Kansas City a call. For an amp, the Music Reference RM-10 was designed using the ESL as it's load, and is perfect for it.

Roger's (rip) RM-200 was the best, as it has 1 or 2ohm output taped transformers, with the 2ohm tap it drove the ESL63’s to perfection, but it’s 100w gets knocked way down from the 8ohm tap figure, but still enough to get decent level out of the ESL 57’s

Cheers George

True George, and the lower the tap, the lower the output impedance, a very good thing with the ESL (it's impedance swing is brutal, insane). Interestingly, in my last email with Roger, he recommended I use the 8 ohm tap on the RM-10 with the ESL, not the 4 ohm. I asked about his "light loading", and he said yeah, but the ESL is mostly a 16 ohm load, so the 8 ohm tap IS light loading with that speaker. When I get my Quads up here I'll try both amps (RM-10 Mk.2, RM-200 Mk.2), and all taps.

My Emotive Audio Vitas drove my Quad 57’s for 15 years without any issues. But I have also moved on the other speakers and right now find my Bache Tribeca speakers to be more satisfying. Maybe I should connect my Quads again during this lockdown. 

I can’t say whether the rebuilders get more bass and treble from the speaker, but there have been improvements to the power supply and the Zener clamp boards allow you to use a wider selection of amps without the fear of arcing the panels. As previously mentioned Electrostatic Solutions is a good resource to learn about some of the design improvements.

As for the RM10 and the ESL 57 well it was somewhat by accident that the amp was designed with that speaker in mind. It just so happened that was the speaker Roger was using at the time so he certainly wanted an amp that could play well with it (actually right to the very end Roger had his ESL 57 running in the shop for our music pleasure). The RM10 is very balanced with the ESL 57, but most amps will have trouble keeping up with the rise in the bass frequencies and the RM-10 could be perceived to be a bit lean there, but overall it’s one of the best tube amps to use with that speaker.

OTL amps can deal with that rise in the bass, and along with the RM10 I have used the Atma-Sphere M60 with these speakers and even though their output impedance is much higher than the RM10, it plays quite well.

I find tube amps that only have 8ohm taps usually sound a bit soft and rolled off in the highs with the 57's, as they are a 2.5ohm load already at 10khz and falling to 1ohm at 20khz.
This is why I prefer a good stable 30-40w Class-A solid state that can do the doubling, I built quite a few of these for 57 owners based on the Nelson Pass A40 and they loved them.
http://www.firstwatt.com/pdf/art_a40.pdf

This is why they say they best amp ever for the 57's, was the Mark Levinson ML2 25w Class-A monoblocks, that could double down to 1ohm.
 https://img.ukaudiomart.com/uploads/large/2229206-mark-levinson-ml2.jpg

Cheers George    

I gave up on my Quad ESL 63s in the late 90's and don't miss them.
I'm definitely a dynamic speaker guy but I WOULD like to own a pair of ESL 57s as well.  I like them better than the 63s (though, ultimately, not as much as some dynamic speakers).

I bought my first pair of 57's back in '81. Along with a pair of Futterman H3aa OTL amps. And around that time a Bedini 25/25 class A amp. I alternated between those two amps. In 2001 I stupidly sold the Quads and the Futtermans. This I soon regretted! Now thanks to good fortune in the past few years I've acquired two pairs of 57's and three Futterman amps!

The 57's in stock form are limited to 20 volts input (50 watts). More than that they will arc! Stay below that and they will be fine! Do not expect to get floor-shaking bass and window-rattling spl's out of them! They are not JBL's!

I had Martin Logan CLSIIs with upgraded ladders, much later Magnepan 3.5Rs (I know not stats),but, both were frustrating in there own ways
DFor 3+ years now I have enjoyed Emerald Physics KCIIs (open baffle) with WireWorld and Clarity cap upgrades. They are very easy to drive, super efficient, glorious mid-range plus very good bass, seamless from top to bottom.

My main nit pics are both easy fixes
* the speaker face and base should have anchor bolts especially since the concentric driver at the top is so heavy

* the rear tilted face angle that EP chose is too extreme. I am using a hockey puck in the rear of the base and small Machina Dynamica springs in the front

hth

A main factor for me is that I am a single ended triode guy. Ever since I started using the magic of 1 1/2 to 8 watts of amp power I have been limited to highly efficient speakers. Fortunately, I finally found a great speaker that works great with my 8 watts of 300B-Tetra 506s. (worth checking out their website and the major musicians who use them!). They are 90db and a very flat 8 ohms impedance. However, I still do miss the ‘57s. Did speak with Kent at Electrostatic Solutions. I believe he has made significant improvements over the original design. Heard that his improved version has way improved dynamics, bass and treble. Does anyone know about this?