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previous: Scroggins Okay I was wrong.When I mix... -- 7/21/2003 11:19 PM

Re: NFB - PI Question

7/22/2003 12:04 AM
jbrew73	Re: NFB - PI Question i'm planing on building a very similar amp and was wondering about the same problems you are having. i was thinking about using 470k mixing resistors although i don't know if it would help but it should give better isolation between channels. my plans are to use a master volume on the dirty channel after the tone stack(just before the mixing resistors) and use a EF86 on the clean side with the volume in the same position. hopefully the mixing resistors will provide enough isolation allthough i think if i turn down the MV on the dirty channel to low it will probably lower the clean channel some. i would like to use both sides of the PI but my signals will be in phase with each other. let me know how this project works out maybe it will save me time and heartache.

7/22/2003 12:04 AM

jbrew73

Re: NFB - PI Question

i'm planing on building a very similar amp and was
wondering about the same problems you are having.
i was thinking about using 470k mixing resistors
although i don't know if it would help but it should give better isolation between channels. my plans are to use a master volume on the dirty channel after the tone stack(just before the mixing resistors) and use a EF86 on the clean side with the volume in the same position. hopefully the mixing resistors will provide enough isolation allthough i think if i turn down the MV on the dirty channel to low it will probably lower the clean channel some. i would like to use both sides of the PI but my signals will be in phase with each other. let me know how this project works out maybe it will save me time and heartache.

Replies:

Scroggins I'll let you know what happens. The... -- 7/22/2003 2:04 AM