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Old 23rd February 2007, 07:38 PM   #1
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Default Bypass input resistor and use a 20k pot instead?

I was wondering if it would be possible to bypass the input resistor on the Charizle board and use a 20k pot such as the DACT in its place. It sounds like it would work in theory, but would it sound better? Thanks for your input guys.
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Old 24th February 2007, 03:53 AM   #2
Pano is offline Pano  United States
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I can't picture how that would work. The input resistor is part of the feedback loop on the inputs. It sets the gain along with the feedback resistor.

How were you thinking of connecting it?
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Old 11th June 2007, 01:24 PM   #3
Stanco is offline Stanco  Italy
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how it would play without feedback? mah....
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Old 11th June 2007, 05:34 PM   #4
Stanco is offline Stanco  Italy
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someone has tried to remove the feedback in input? ciao
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Old 13th June 2007, 06:05 PM   #5
xenob is offline xenob  Austria
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it should be possible
look at this thread

http://www.41hz.com/Forums/topic.asp?TOPIC_ID=582

"Input Gain = - Rfdbk/Rin. With Rin=22K you can trim Rfdbk from 50K (gain=2.2) to 1K (gain=0.04).

In theory that could replace volume control."
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Old 13th June 2007, 09:04 PM   #6
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I'd be careful with that!

The input stage of the amp is an opamp. Running an opamp at less than unity gain (gain=0.04) can cause all sorts of stablity problems.
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