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    Building, troubleshooting and testing of these amplifiers should only be
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    the safety precautions around high voltages.

PS for GG - look for better channel separation

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I am trying to improve my scratch built GG's channel separation. Among other factors, the psu is a place to work on. Currently, it use a single psu for both channels. Reading from others posts, I understand that one way to improve is to let each channel has its own final stage in the ripple filter.

The current schematic is here. Zener is 100V each, B+ and B- required are 200V. All cap shown are each 3X100uF (i.e. total 18 cap). I am thinking of spliting the last stage cap (i.e. C9 and C12) and use the cap for each channel like in the "after" image. So C9 C12 become 2X100uF and new cap in the scheumatic is 1X100uF. Do you think it will work?

By the way, I found V drop across R17 R19 which make the B around (195V). Can I move it before the zenor?
 

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Thank you. Thank you. Thank you. I must have lost my head. Here is the correct one. To recap my questions:

1. Will spliting the last stage cap this way ok?
2. Should I move the R17 before the zenor to avoid V drop?

Thanks for your help.
 

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senderj said:
Nobody answer just because I made a mistake?
Oh dear :angel: I dont think its like that!

You may consider branching out just after C2. Each rail its own Zener string. C2>Rx2>C3x2>Zx2>C4x2 . What B+ are you looking at ? You can be comfortably in the region of 200~220 VDC. Do you have a CT Power TX secondary? Then you may consider using a bridge.
 
carbato,

Thank you for the reply. By C2, I guess you mean the second stage of the filter (i.e. C8 & C11). Am I right?

For the C2>Rx2>C3x2>Zx2>C4x2, do C3 and C4 be the same value as C2? Can they be smaller?

I don't know what is CT Power TX secondary. If it means another 220VAC output, then I don't have. There is only one set of 220VAC from my transformer, so I cannot use 2 bridges.
 
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