2. amps-preamps
  3. 139915-2206

Bypass capacitor position?

Hi all. I've had a pair of Coincident Frankensteins for a number of years and just opened them up to put in new capacitors.  In doing so, I discovered that the previous owner had installed bypass caps on the power supply capacitor bank.  Those bypass caps are, however, in different positions on the two monoblocks.  Obviously they're both within the same capacitor bank, just linking different parts of the chain, so perhaps that isn't an issue.

Sometimes I think I can hear a small difference in the two amps, but if it's there it's really subtle and I may be creating a self-fulfilling prophecy.

Can anyone provide input on if this fact will change their operation/sound?  I'm trying to figure out whether to cut one of them out and move it, and if so, which is the appropriate position...

Monoblock 1:  https://photos.app.goo.gl/NMGYvU1sdHbGLqb37
Monoblock 2:  https://photos.app.goo.gl/ogDkNio1DyqvM1rs6

Thanks...
cal3713
erik_squires
16,901 posts
 
@grannyring

Nope, just in crossovers. :)

Best,
E
johnsonwu
469 posts
 
small difference in the 2 amps....  the Frankenstein uses a "Hail Mary" type of biasing on the 300B as far as I can tell.  The sound is very dependent on the plate voltage of the 6EM7.  Good luck getting the 2 to sound the same.

cal3713's avatar
cal3713 OP
1,421 posts
 
Thanks for the input everyone. I went with the tinned copper cast option. Figured I might as well match the speaker cables... And just a step more expensive than the straight coopers. Not eye watering like the silvers.

@grannyring I read on one review (either that huge capacitor comparison site or jeffspace) that they didn't like the silver bypass on those tinned-copper caps. Might still give it a shot though... Thanks for the suggestion. (And the power cords sound great. I tried to go back to stock and it was a huge step back)
grannyring's avatar
grannyring
6,646 posts
 
I did not use the silver bypass caps  on the tinned copper Duelund caps. I only used them with the CAST. It may not sound good with the tinned copper caps, I  just don’t know. I thought you used the original CAST line.
atmasphere's avatar
atmasphere
12,180 posts
 
I agree. All looks fine to me.  Nice to see an all film cap power supply.  Not often done, but really is a nice improvement in SQ.
@grannyring

FWIW there are electrolytic capacitors used in this amp. There are 4 of them visible near the top of the photos.

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