diyAudio (
-   Pass Labs (
-   -   Pass Amps and ESL speakers (

G-Daddy 4th November 2001 01:40 AM

I've been posting in the loudspeakers section for a bit, time to try out another topic on the minds here . . .

In our research into electrostatic speakers, we've been told time and again (most notably by Roger Sanders in the Electrostatic Speaker Cookbook) that power is the most important quantity in choosing an amplifier to drive ESLs.

I come across people on the internet often who're building 200 watt amplifiers to drive their electrostatics. I am now considering an amplifier project to drive the set of ESLs I intend to build. My friends and I've cleared the major hurdles of ESL production, and am in the research mode of an amplifier now.

Now I'm also coming across people who've build various models of Nelson Pass paternity, rated around 10 watts or so, that "sound great on my ESLs". What's going on here? How can a 10 watt amp power an electrostatic speaker? What am I missing? If I'm right here, P=V^2/R . . . V = sqrt(P*R) . . . leads to a 10 watt amp on an 8ohm resistance producing about a 9V max output voltage. To power an electrostatic, you'd need a pretty large transformer to achieve the stator voltages necessary for proper membrane force. What's am I missing here? Should I be planning a 200W power amp, or should I be studying the elegantly simple Zen 10 watt-ers? Any help that can be provided would be immensely useful. Thanks.

- Jonathan

djk 4th November 2001 09:39 AM

About 30 years ago Audio Amateur published a 100W class A triode amplifier that was direct coupled for ES use.In push-pull a single pair of $10 each 811s will do 200W and swing 2.5KV P-P.

hakalugi 4th December 2001 01:13 AM

^^^bump to top^^^

anyone else run ESL w/ Pass (diy) amps?

Dave 4th December 2001 05:25 AM

Isn't the Quad ESL 57 designed to run off 15 watts?

jam 4th December 2001 01:44 PM


The answer depends on the electroststics you use. You could get away with 20 watts with the Quads but would need about 200 watts with Sound Labs to get any reasonable volume.

Several factors have to be considered in the design, one is the stator to membrane distance and the other is polarizing voltage, you have to juggle these variables and decide if you want to sacrifice bass response for efficiency. The other consideration is the turns raito of the transformer, there are pratical limits to what you can achieve.


All times are GMT. The time now is 06:10 AM.

Search Engine Optimisation provided by DragonByte SEO (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Resources saved on this page: MySQL 18.75%
vBulletin Optimisation provided by vB Optimise (Pro) - vBulletin Mods & Addons Copyright © 2018 DragonByte Technologies Ltd.
Copyright ©1999-2018 diyAudio