• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

HV Direct Drive tube amp.

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Just a quick comment- the ESL is a Push-Pull driver. Your amp, as shown here is a single-ended amp. One of the stators will be permanantly grounded, meaning that your ESLs will only be driven from one side. I undertand that this does not sound very good at all.

James

P.s. Perhaps you should look at scaling up John Broskie's second Electrostatic headphone amp (TCJ December 1999. Input on page 3, output on page 5).
 
And yes since were at it, the split load/ cathodyne phase splitter needs equal cathode and anode resistors, f.ex. 22k with a 6SN7, the lower cathode resistor I don't know how to calculate.
The capacitor value should be found by the usual formula, I guess a couple of uF's would be plenty....

But the whole simulation in the Push-Pull calculator shows extreme sensitivity to bias voltages etc., seems a little scary...
 
Hi Knubie,
Yes, You have noticed. We were talking about safety and no one to
offer help to calculate circuit. Well...
I think 6HV5 is much better than 6HB5 for this application since
5kV B+ is needed . 1kV output is not enough.
You really need 8-10kVpp for serious listening.
Until somebody with knowledge of tube circuits calculate
values for me I don't feel comfortable experimenting with this.
It's too risky .
Regards.
 
Hi Flavio,
My e-mails to You are coming back.
I guess You have some spam filter
not letting my e-mails go through.
Will try again.
> Hi Flavio,
> The mod to triode is simple. Omit R40, R39, C24, jump cathode to G2, no +150V to tubes
> increase R37 from 10K to 18K, no input amp& eq. Don't know how to use tube input stage
> but I was planing to do it with LM3886 ( no time yet). Ceramic bases from www.thetubestore.com
> It doesn't matter 2 or 4 tubes per board just leave enough space between HV lines and the rest.
> P to P is quicker and probably better since You can use HV wire where needed.
> If you have HF oscillation on output try to ground G2 of V2 with some small cap till You
> loose HF.
> Regards
>
 
Flavio

hi Sasha
thanks a lot to answered to my questions, I never thought that your mail back to you, I have a spam filter, but now I decrease the level (don't use spam and "sasha" as subject should be good)
The good thing is that you receive my mail and I'll tell you my
private email and my job email (try both)
1)You say "jump cathode to G2" you want tell jump the cathode of V1 to anode of V2 with 10K/15W R38 and anode of V2 to grid of V1 with 10K/4W R37, and you connect R36/C29 to grid of V2?
2)How much is the voltage of R43, r38, R37, R61?
3)Which high voltage diode rectifier did you use for the 2KV?
4)In a mail you said that you decreased the low resistors to obtain the maximum output current because the tube are triode,
which resistors did you changed and which are the new value?
5)May I eliminate the 12V circuit if I use manual turn on?
6)An update say to eliminate R22 and ground connection, is it correct?
7)Where do you connect the front plate driver?
8)About V68Z2, S 3217, SC 142D is there something better,
may I can eliminate something?
I'm new and I can't reply to you so I use the forum and I don't know how to find your next answer (but in some way I'll do it)
(sorry if my english is not good)
thanks again a lot for your help
Flavio
 
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