Has the notion of an F3X ever been discussed? I searched and did not find anything. The application would be direct drive of electrostatic headphones or even full-size ESL panels.
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.
it looks easy on paper (hell of a cascoding, plus converting a core to LTP, should solve most of puzzle) but certainly needing decent polishing time
so, lemme pass that one, no need to be wise-a$$ if I'm not planning to invest bench time
so, lemme pass that one, no need to be wise-a$$ if I'm not planning to invest bench time
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.
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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yup Kwayzee Danske MetalKid - Magura
later resorted to games making money
schematic was result of his insisting on concept and me making patches
these days I'll do it differently, most likely
later resorted to games making money
schematic was result of his insisting on concept and me making patches
these days I'll do it differently, most likely
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.