Kevin O'Connor master volume mod?

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Mark
Posts: 2982
Joined: Sat Jan 15, 2005 8:10 am
Location: Sydney Australia

Kevin O'Connor master volume mod?

Post by Mark »

I was wondering what the concensus is on the KOC mod where he puts a 100K resistor off the wiper of the 1M pot and into the phase inverter.

It was popular when he came out with it, but I notice it has been omitted from Dumble ODS amps.

What are your thoughts on the matter?

Thanks for your time and assistance.
Yours Sincerely

Mark Abbott
Roe
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Re: Kevin O'Connor master volume mod?

Post by Roe »

It depends on the circuit. some high gain amps benefit from a resistor, preventing blocking distortion in the phase inverter. others do not need it
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Mark
Posts: 2982
Joined: Sat Jan 15, 2005 8:10 am
Location: Sydney Australia

Re: Kevin O'Connor master volume mod?

Post by Mark »

The basis of KOC recommendation was bass and mids roll off. Without the resistor the amp sounds tinny. I vaguely remember encountering something like this in the past. I'll try looking for it in one of his books.
Yours Sincerely

Mark Abbott
frankdrebin
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Re: Kevin O'Connor master volume mod?

Post by frankdrebin »

I won't go on theory, I say just try it, I think you'll get the reality.
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roberto
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Re: Kevin O'Connor master volume mod?

Post by roberto »

With concertina phase inverters you can increase it as much as you want, but with LTP you have to compromise with the miller effect of a stage that has gain (so roll off of highs).
You will probably find a good compromise with something between 1/10 and 1/5 of the pot value.
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