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High-End Tube preamp with ECC88

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BTW, B+ at 220 Volts seems a "bit" low, given the voltage on the base of the BF459 at 204,7 Volts and the upper 270K of the voltage divider....


Please be more concrete, in this case, what needs to change!
Maybe I should be like this:
thank you!
 

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Please be more concrete, in this case, what needs to change!

Where to start?
Sorry to be a curmudgeon but try the usual suspects.
a) get rid of the silicon PN rectifiers and replace with quieter types. Schottkeys or valve diodes.
b) replace the anode follower with a current source or inductor or output transformer (eg LL 1660/10mA or better)
c) change the capacitor input filter to a choke input filter.
d) replace resistors in RC circuits with inductors.
e) 6DJ8 is a good tube but nowhere near the best - even a 6SN7 would (on average) be better.

Finally, a bit speculatively, replacing the series B+ regulator with a shunt regulator (eg. 0A2 ) is widely recommended by those who try it - if not so easy to clearly stand behind technically.
 
and why change the 6CG7 mu follower to ECC88 SRPP :confused:

Because the idea of the REDD DI is to add tube tone to a bass guitar. The 6CG7 is a very linear tube and the mu follower is a very linear topology - not much tone there. The 6922 is a less linear tube and the SRPP is a much less linear topology so both changes add tube tone.

Cheers

Ian
 
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