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Old 18th March 2014, 12:50 PM   #1
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Default Guitar preamp, lowering output voltage

Hi,

I have built guitar preamp, which has too much output voltage swing. I measured with cheap DMM about 20V output swing. Where is the best place to put voltage divider 10:1 to reduce output voltage? I was thinking after the tonestack or after the presence control? It could be also after the mosfet buffer, but I think less voltage going into buffer more linear it stays.
Also what about replacing 470k/500K volume pot network with 1M/25k volume pot?

Thanks.
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Old 18th March 2014, 01:38 PM   #2
Ketje is offline Ketje  Belgium
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Why is this a problem? There is a potmeter between V1A and V1B,turn it dawn !
Mona
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Old 18th March 2014, 01:57 PM   #3
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You misunderstand me. Pot betwwen V1A and V1B controls amount of distortion not output level. I need to lower output voltage swing after the tonestack somewhere.
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Old 18th March 2014, 02:08 PM   #4
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Replace 220R/1M resistors on the output with a potentiometer or a fixed voltage divider.
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Old 18th March 2014, 03:38 PM   #5
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Default Solved

See attached schematic...
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Old 18th March 2014, 07:00 PM   #6
Ketje is offline Ketje  Belgium
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Quote:
Originally Posted by kacernator View Post
You misunderstand me. Pot betwwen V1A and V1B controls amount of distortion not output level. I need to lower output voltage swing after the tonestack somewhere.
Ah yes, you want the thing to distort
I am used to have amp's with as less distortion as possible
Mona
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