Advice on transformer coupled input / driver

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I am trying to come up with a suitable driver for the triode connected el34 amp shown in the link below. I would like to keep it simple and transformer coupled. I plan on changing the operating point of the el34s slightly to Va + Vrk =430, Rl =10k, Rk=250 (un-bypassed). Per the mullard data sheets, I need to swing 44 Vrms g-g.

The schematic is my first crack at it but Iâ€™m not much of a designer. Do you see any obvious problems or have any advice for improving it?
As far as the original schematic, it all makes sense to me with the exception of the small capacitor between the cathodes of the output tubes and the center tap of the input transformer secondary. Does anybody know what the purpose of this capacitor is?
Thanks in advance for any advice.
Marty

http://www.tube-amps.net/images/EL34_PP_NNFB_01/EL34_Schematic.jpg (Open in New Window)

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Topic - Advice on transformer coupled input / driver - martyh 10:04:52 03/03/07 (7)

Re: Advice on transformer coupled input / driver - Dave Davenport 22:26:59 03/03/07 (5)

The designer is Tadaatsu Atarashi - martyh 05:21:27 03/04/07 (4)

Re: The designer is Tadaatsu Atarashi - Dave Davenport 08:47:16 03/04/07 (3)

Thanks! - martyh 10:29:51 03/04/07 (2)

Re: Thanks! - Dave Davenport 13:56:35 03/04/07 (0)

Re: Thanks! - arend-jan 11:47:57 03/04/07 (0)

Re: Advice on transformer coupled input / driver - AndreasS 11:25:39 03/03/07 (0)

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