tube amps and electrostatics


What kinds of experiences have people had mating tube amps to electrostatic speakers (full range and/or hybrids)? I love the sound of both separately, but am concerned about the reactance of electrostats with tube power. I already own the CJ CAV-50 and am looking to upgrade my speakers with something in the $2500 range. Thanx, Dave
dabble
Bruce, I would not loose heart!

The issue that makes ESLs hard to sort out is that their impedance curve is related to a capacitor rather than drivers in a box.

But the allure is of course that ESLs are very fast and revealing, and if set up right, not painful for all that extra detail.

I agree that some things about ESLs can be counter-intuitive. For example many magazine articles have been written about how hard they are to drive, difficult load yada yada, but that really isn't the case.

OTLs, as you know, have a reputation about being load sensitive, but oddly have also been the preferred combination with ESLs going back to the 1950s. We have made that even more difficult for ourselves (since we make OTLs) by removing the feedback from our amplifiers, yet still they are able to drive ESLs quite well. So the 'difficult load' thing is really a common myth not supported in the field.

What *can* make an ESL hard to drive is when the manufacturer of the ESL decides he wants the speaker to be more transistor-friendly. MLs are a good example- 4 ohms in the bass, 0.5 ohms at 20KHz. Now there are many who would say that is a difficult load, but there are no crazy phase angles, so with proper matching (a set of ZEROs) such speakers become quite easy to drive with tubes since its more about impedance than anything else.

If you are contemplating going from a box speaker to an ESL, you may have to deal with things like having the speaker further into the room to make it play right. However the energy that comes off the back of the speaker is used by the human ear/brain system to get a better idea of where the sound is coming from; IOW to improve the soundstage imaging.

So I would not write off ESLs just because some things about them are counter-intuitive. If you have questions about whether a certain ESL will work with your ARCs, all you have to do is ask... I can tell you though that the combo will be good with Quad ESL57s and 63s, you will want the ZEROs with their later models, similarly with nearly all MLs. You will be able to drive Sound Labs directly no worries (however you will want the latest version of the backplate as it corrects a crossover error, making the speaker a lot better sounding and easier to drive), also King, Audiostatic and Accoustat. You will need a set of ZEROs with the Sanders ESLs as they are low impedance.

Also, your amp will be able to keep up with solid state amps, often with the ability to play with as much power as solid state amps of considerably higher power rating. This assumes the match is good (meaning that even if a set of ZEROs is needed, this will still be true).
Es speakers are special and worth any special effort needed. Plus you have some good sidekicks here that can help to get them singing.
Wouldnt two ohm or less impedance at high frequency be much easier for a ss amp in particular to deal with than if it were low? Way less power needed for high frequencybthan low. Or is it more complicated than that?
^^ yes. But then you are dealing with 20 ohms or more in the bass. A 600-watt transistor amp just became a 250-watt amp.

This is why tubes work so well- the higher impedances are not as challenging. In the case of the Sound Labs, this means a 150-watt tube amp can keep up with a 600-watt transistor amp no worries.
"I will say this. Any interest I had in trying ESLs is gone. It seems that amp/ESL compatibility is counter-intuitive. So I'll stick with what I have." Bifwynne

If you have not experienced a well done ESL system, you are missing out on the best! If you are located close enough to be practical (N. California), you are welcome to come hear mine.