What kind of power wakes up electrostatic speakers

Bear, i have seen impedance charts for Acoustat's that show a dip below 1 ohm at appr 10 KHz. From other charts that i have seen, this is pretty normal for a LOT of E-stat's. While the dips may not be quite as extreme or at the same exact frequency, they all tend to frustrate amps at high freq's. The saving grace of all of this is that there is not a ton of recorded info up that high and what is recorded is not of a high current demand like low freq's.

I would also think that a speaker with an impedance of 6+ ohms ( even with a reactive phase angle ) would not be too tough for a decently built amp to deal with. The fact that Acoustat's put MANY, MANY amps to shame and can suck most "high powered" monsters dry somewhat contradicts your previous statements. What i'm trying to get at is, what info did you base your nominal 6 ohm impedance figure on ? As mentioned, i'm going by the test measurements that i've seen and the experiences of more than a few Acoustat owners. Sean
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I'm using a Innersound esl amp to drive my Magnepan 1.6's and with good results. Before I bought the Innersound, I was using a Odyssey Stratos amp. The Odyssey was quite neutral, but at the same time, compressed the soundstage when pushed at higher volume. The Innersound compared to the Odyssey exhibited tighter bass control, unrestrained dynamic swings, more air around voice and instruments, better micro and macro details, and overall better control of my speakers. I haven't looked back on my purchuse of this great amp from Duke at Audio Kinesis. I'm in no way affiliated with Audio Kinesis or Innersound audio, but rather a very happy owner of the Innersound esl amp! Thanks again Duke!

Sean, which Acoustat?? All of the Acoustats that used the 121 type interface - that included the II,III, IV, VI, VIIs
absolutely do NOT have any impedance dip below 6 ohms. I am not convinced that any did, unless they stopped using Jim Strickland's patented "bi-former" interfaces with the last of the breed - the hybrid Spectra series stuff.

This is the published data for those speakers. My own tests confirm this. Indeed it is the basis for the patent.

As far as the Acoustats "sucking" amps dry is more due to the large voltage swings required for peak output, and deficits in those amplifiers' design. Since ESLs tend to have lower distortion than many cone speakers, the onset of
"distress" is easily heard.

On the other hand, I know at least one person with a very nicely done 35 watt tube amp that drove them with no trouble at all.

Quite a lot of people ran them with receivers too - as long
as you didn't stress the amp (play too loudly) they sounded pretty much ok.

So, I'm not sure what sorts of problems you've encountered with Acoustats - again if it is the later "Spectra" series, all bets are off, as I have no idea what they ended up doing towards the end of the product's life.

I owned Acoustat IVs for many years. Anyone interested in electrostats should visit this site:

http://www.audiocircuit.com/

It contains all the original information on virtually every electrostat ever made. It includes a copy of the original paper "The technology of full-range-element electrostatic loudspeakers" by James Strickland, President of Acoustat Corporation.

This paper includes a discussion of the interface and amp requirements. It also shows the impedance curve for the Acoustats which dips to 3 ohms.

I'm very happy with my Mcintosh MA-6500. It sounds great, has more than enough power, and great features. The MA-6900 is another good one to consider.