Anyway, MtA looks quite neat. I do think that the lower impedance of the Grado cans ought to be driven w/TX coupling. I am examining the RK34 for a linestage valve. It looks like ~2W is available with 250V and 10k a-a. More than enough power I think. Put a CCS under the cathodes and Class A is insured. Now to find out if these things are matched section-section. This would be a voltage gain of ~1/2 and would be the PP eauivalent of the 'Spud Amp' One twin element valve per channel and the PS. Probably get another Heyboer 8039. The amp will consume less than 80 mA in total.

My general MoO has been to step out with my own design, and THEN do some more research if the design does not show any promise. The traditional methods will no doubt yeild traditional results. I am seeking more. Now to find a proper 10k:32 OPTx. Perhaps the low power will allow me to ratio a 10k a-a into 20k by running the Grado's on the 16R tap.

regards,
Douglas