have none of these, so - it didn't crossed my mind
The first electrostatic speaker I listened to was at a co-worker's house. It was Acoustat model X which had a direct drive tube amplifier. The sound was very different from any other speaker and in a good way. The speakers are push-pull and the THD is on the order of 10X lower than voice coil magnet speakers.
That led me to build a pair of Roger Sanders DIY ESLs in the 1980s. They were driven using a pair of UTC tube transformers that I still have. I always wanted to listen to ELSs with a direct drive amp.
Now I have Stax Lambda and Stax Gamma ESL headphones with a Stax SRM-313 direct drive amp. It uses Toshiba JFET inputs a-la Pass but all the rest is garden variety BJTs which I would like to transform into SIT driven output stage a-la Pass F3.
The DC rails on the Stsx amp are + / - 300V and the bias on the diaphragms is something like 240V.
I think an F3 based design can be DC coupled for this application.
umm . . .
That was followed by what I am convinced is easily the single greatest perpetration of diyaudio in history.
donut-a-la-overkill
Called the Choky Susy F3 or Donut a'la Overkill
There is a pic in one of the threads where they were pouring the case at the foundry. Epic. Attached is one pic I keep and look at when I need inspiration.
For those who have been hording LU's or waiting for a balanced F3 amp, ZM proposed the following.
That was followed by what I am convinced is easily the single greatest perpetration of diyaudio in history.
donut-a-la-overkill
Called the Choky Susy F3 or Donut a'la Overkill
There is a pic in one of the threads where they were pouring the case at the foundry. Epic. Attached is one pic I keep and look at when I need inspiration.
Attachments
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It isn't X-ed, only bridged:
So, this is my Quad ZV9!
Once upon a time, I have listened it with Focal Jmlab Vega speakers, sound was comparable to a factory Pass XA30.5.
Of course that was better.
But I was not ashamed of my amp.
So, this is my Quad ZV9!
Once upon a time, I have listened it with Focal Jmlab Vega speakers, sound was comparable to a factory Pass XA30.5.
Of course that was better.
But I was not ashamed of my amp.
It isn't X-ed, only bridged:
So, this is my Quad ZV9!
Once upon a time, I have listened it with Focal Jmlab Vega speakers, sound was comparable to a factory Pass XA30.5.
Of course that was better.
But I was not ashamed of my amp.
Congrats on a very nice amplifier build.
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