[glynnw]

I just received a pair of Sound-Lab A-3 speakers and while they sound superb, they are extremely power hungry.  My abt 90 watt tube amp will drive them to moderate levels, but no hard core rock.  I am considering one of the high powered Class D amps, but my electronics knowledge is limited (OK - it's non-existent).  Are there some characteristics of a class D combined with electrostatics that simply make them incompatible?  I am thinking 500+ watts will really open these sweethearts up.  BTW, what I do hear is some of the best sound I have ever had.

[opnly bafld]

Have you read the review in Stereophile?
Sounds like they might blow up if you try to use all of a 500 watt amplifier.
Class D or AB solid state, the speakers will reward use of a quality amplifier.

[richidoo]

If speakers are not playing loud enough then they need more voltage. Make sure your source/preamp signal is high enough voltage output to drive the amp to full power. Make sure the preamp gain + amp gain is sufficient to drive the speakers to your desired loudness. Less sensitive panel speakers usually need more voltage than typical box speakers to play as loud. They usually also have lower impedance so the higher voltage demands more current, and the resultant voltage x current = power, and applying more power than the speakers power rating will break it. This is why Lin is cautioning you to be careful. The speakers may not be capable of playing as loudly as you desire them to play due to their limited power handling.

The trend these days is towards lower voltage gain electronics, so it could be your amp/preamp doesn't have enough voltage gain to play as loud as you want, even if the speakers are capable.

If it is just too soft and no distortion then you need more voltage gain from preamp, amplifier, or both.

If you hear distortion when you turn it up then either the speaker is distorting because you are pushing it louder than its capable of playing (speaker power rating exceeded) or the amp is distorting because it can't source enough current for the voltage requested and you need amp with higher power rating.

^That's the electrical basics.

The finer point is that amps are not power-rated with any kind of standard. So a "100W" class AB "high end audiophile" type amplifier often sounds stronger and more refined into the same speaker load as a "600W" class D consumer amp that is optimized for price and low energy consumption. The 100W amp will probably cost more than the 600W based on the real world music performance and sound quality.

[artur9]

The pricing of Class D amplifiers is compelling.  OTOH, the Sanders MagTech was explicitly designed for panel speakers.

https://www.enjoythemusic.com/magazine/equipment/0719/Sanders_Sound_Systems_Magtech_Amplifier_Review.htm

[Freo-1]

The pricing of Class D amplifiers is compelling.  OTOH, the Sanders MagTech was explicitly designed for panel speakers.

https://www.enjoythemusic.com/magazine/equipment/0719/Sanders_Sound_Systems_Magtech_Amplifier_Review.htm

I like this option for ESL speakers as well. 

[I.Greyhound Fan]

PS Audio M700 or 1200 amps.  700 wpc at 4 ohms for the M700 and 1200 wpc for the M1200.  Read the Stereophile reviews.

[ACHiPo]

I just received a pair of Sound-Lab A-3 speakers and while they sound superb, they are extremely power hungry.  My abt 90 watt tube amp will drive them to moderate levels, but no hard core rock.  I am considering one of the high powered Class D amps, but my electronics knowledge is limited (OK - it's non-existent).  Are there some characteristics of a class D combined with electrostatics that simply make them incompatible?  I am thinking 500+ watts will really open these sweethearts up.  BTW, what I do hear is some of the best sound I have ever had.

Not an answer to your question specifically, but maybe it will help...

I drive my Majestic 745s with either AtmaSphere MA1 monoblocks (140W OTL tube power at 8 Ohms) or Benchmark AHB2 Class H monoblocks (380W into 8 Ohms, 480W into 6 Ohms).  Both are adequately powerful, but struggle to get above ~95 dB A-weighted SPL.  The Sound Labs are great speakers, but have definite limitations when it comes to realistic sound pressure levels.  That said, I find listening at ~80 dB is more than loud enough for me.

[Blackmore]

I've had inexpensive class D amps buzz and shut down when trying to drive my Innersound Eros stat panel.  The Eros are very sensitive, but the impedance drops near 1 ohm in the treble which some D amps may find troublesome.  I would certainly check with the manufacturer to see if the amp you are considering can drive such low impedances. 

I drive my Innersounds with the Innersound ESL amp (Magtech's predecessor) or a BAT VK60 and they have no issues.  But again, the Innersound is quite sensitive, so that doesn't address your problems with the Sound Labs.

Hope this helps a bit.

[Jazzman53]

I would say YES.

My speakers are fairly large homebuilt bi-amplified hybrid ESLs which I normally power with a pair of vintage class G  Carver TFM-25 (225w/ch) amps.  Whereas most commercial ESLs are an all-capacitive load, mine are a partially-resistive / partially-capacitive load, so bear that in mind.  The Carvers drive them with aplomb.

A built a pair of these same ESLs for a friend who powers the electrostat panels with a pair of these VTV NC2K class D mono-blocks:  https://vtvamplifier.com/product/vtv-amplifier-monoblock-hypex-nc2000-ncore-amplifier-2000w-with-vtv-buffer-input/
 
These VTV amps use Hypex NCOR NC2K class D amp modules, which have PRODIGIOUS power and sound fantastic.  My friend barely cracks the throttle on these monsters to make the ESLs really sing. 

Obviously, these VTV mono blocks have headroom that lesser class D amps would not have, but I can tell you that these sound as good as any amps I've ever heard, regardless of type/class, and they don't break a sweat driving my my ESL design. 

BTW; the ESL's referenced above are shown on my website here:  http://jazzman-esl-page.blogspot.com/?m=0

[whydontumarryit]

Move the speakers closer to the listening position or vice versa. 4 times the power for free.

[mick wolfe]

I just received a pair of Sound-Lab A-3 speakers and while they sound superb, they are extremely power hungry.  My abt 90 watt tube amp will drive them to moderate levels, but no hard core rock.  I am considering one of the high powered Class D amps, but my electronics knowledge is limited (OK - it's non-existent).  Are there some characteristics of a class D combined with electrostatics that simply make them incompatible?  I am thinking 500+ watts will really open these sweethearts up.  BTW, what I do hear is some of the best sound I have ever had.

  I have a friend who at one time (years ago) owned the largest of the Sound-Labs. He had an extremely difficult time finding an amp that could properly drive them. He finally settled on a very expensive and powerful pair of Bryston mono amps. This said and depending on the vintage of your particular Sound-Lab speaker, all this may be a moot point. I would simply contact Sound-Lab and ask them for advice and what they use as a reference. This specific to your particular speaker of course.