Mmmm lots of tasty iron.I'm thinking about building a 205D Phono with a combined line stage. I'm possibly interested in some nickel or amorphous core chokes, output transformer, and maybe the transformer volume control
I can do chokes for both LC and LR riaa, but the high Rp of the 205 will not make it easy.Do you also do a RIAA equalizer out of chokes?
Iirc, the 205 only has a gain of ~8, so my guess is three of them will not get the job done. With an input step-up, 3 of them might get you close to .25V output, but then you will need another stage to get that to the 2V "standard". Thomas Mayer did a all DHT phono stage and used 4 stages of 801's and I think it was an article in sound practices, maybe you could dig that up for a starting point. I must admit the idea of 8 205D's in a phono stage would surely get some attentionAnyway could you give me any recommendations? There would
probably be a total of 3 205D tubes per channel, two phono and one for line
on each channel.
Tossing a high mu DHT in the mix like a AV-30 or 841 sure would help keep it to three stages, but you still have the high impedances to deal with.
dave