ESL amp with 1:4 stepup transformer

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Hi Bas,
How would you maintain a constant plate loading?
I think you would need some kind of impedance compensation network.
Or maybe it`s not so importent?
There is another issue of high freq ringing that needs to be delt with,How do you plan to control the ringing?
 
More ESL stuff

Bas Horneman said:
Hi FB,


Yep, changed that to 0,056uF allready.



Yes, I thing you are right...what were you going to use again?
EL36 or something?


I doubt the transformer as well by the way...

Cheers,
Bas

Hi Bas ,
You could probably use an even smaller value for the couplers . Low value 1% toleranced Vishay polyprops are available very cheaply , the smaller the cap , the better if you ask me ! If using a low value , you could always just use the couplers as a simple 1st order crossover within the amplifier instead of an external one . The valves I was intending on using were EL38's , but these were for direct drive running at 480V as triodes . (EL38 have mu of 16 and Ra of 1.9k as triodes) However for step-up usage I would recommend a low Ra device such as 5998a , 6528 or triode strapped 12E1 , EL34 etc or better still a 2A3 . Mind you though , the 6EW7 would make an excellent starting point to build from ! Maybe not ear-splittingly-loud but there should be enough to get a working setup !

316a
 
just use the couplers as a simple 1st order crossover within the amplifier instead of an external one

Excellent idea!

better still a 2A3

Yep, was thinking that too...like you said..the 6ew7 might be a good starting point..



Hi Ben,
There is another issue of high freq ringing that needs to be delt with,How do you plan to control the ringing?

What do you mean?

Cheers,
Bas
 
Bas,
ESL panels are capacitive load and this couses peaking in the freq response,which on all ESL`s is being controlled with a serias resistor to the primery coil.
Do you have an idea for the tuning resistor position in your case?

It`s a fine expriment,let us know if there`s a solution for that problem.

BenY.
 
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