6AS7 black Magic Voodoo amp

 

Will present this amp at the Paris Hi end Show

SOFITEL PARIS PORTE DE SEVRES
16-17 AVRIL 2005 - 10 h - 19 heures

Well once a while we get tired of 300B's and KT88 and EL type tubes and high voltages and just want something cheap but still very good.

Thats the other design challenge, as good as possible and as simple as possible and as cheap as possible .........................

So Stephan started thinking, sub 500 euro tube amp, is it possible! Without EL84 or EL34. And offcourse something original as well!

And suddenly he had the answer, 6AS7 , 2 double triodes each can handle 13watts, thats like 2 EL84 but 1 watt more and its TRIODE.

The other big advantage is that its Rp is low, so its easy to get a good output transformer.

Will work with LL1664PP and also with a toroid. ( which i still have from my old days of EL34 and 300B push pull amps )

The Schematic :

 

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Direct coupling, needs 2 powersupply voltages and EF86 driver tubes in long tail phase splitter. Very simple and more then enough gain.

Ef86 is also a very musical tube with excellent audio characteristics.

 

The Pcb


A few pictures


All parts can be supplied, PCB on demand and transfomers toroids while stock lasts.

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