5G9 electrolytics in powersupply question

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jezzbo
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5G9 electrolytics in powersupply question

Post by jezzbo »

Hi all,

I'm building a 5G9 Tremolux amp.
http://www.thevintagesound.com/ffg/sche ... _schem.gif

I have allready a question about the elco's in the powersupply.
According the schematic there need to be 4 20uF 500V electrolytics.
But I noticed that the first two are connected in parallel.
So that would make a total of 40uF right?
Is it ok if I used two 80uF in series instead?
Also for a total of 40uF.

Would there be any sound difference you think?

Thanks!
Roe
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Re: 5G9 electrolytics in powersupply question

Post by Roe »

should be ok, minimal difference in sound. the quality of the caps matter more
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ToneMerc
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Re: 5G9 electrolytics in powersupply question

Post by ToneMerc »

I usually will substitite two equivalent caps in series with balancing resistors. So for 40uf, I would run two 80's with 220k resistors.

TM
jezzbo
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Re: 5G9 electrolytics in powersupply question

Post by jezzbo »

Ok, thank you guys. Just wanted to make sure.
PaisleyTube
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Re: 5G9 electrolytics in powersupply question

Post by PaisleyTube »

2 e-caps in parallel gives lower esr

tubeampdoctor.com sells nice 20u/550V caps (you can also try Sprague 20u/600V ones but they're HUGE)
Chris
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jezzbo
Posts: 171
Joined: Fri Jan 04, 2008 12:05 pm
Location: Lebbeke, Belgium

Re: 5G9 electrolytics in powersupply question

Post by jezzbo »

I did not know about the the lower esr.
I do have 4 20uF caps, but at 500V.
Just was wondering about if it was possible to use 2 80uF @ 450V wouldn't be better. (2X 450V in series = 900V right?)

So is 500V caps in parallel enough for this amp?
PaisleyTube
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Re: 5G9 electrolytics in powersupply question

Post by PaisleyTube »

2 x 80u in series will give a tighter low-end (be sure to put a 220k resistor across each one)

500 V is enough but the "series-thing" does something else regarding "energy"

to stop making it too complicated: just use those four 20u/500V ones and enjoy the amp!
Chris
Love, peace & loudness!
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