Question about resistor in boost section of LaVache

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Question about resistor in boost section of LaVache

Postby fishfude » 08 Apr 2017, 12:22

Hi Folks,

I have a question about the purpose of the 3.3M resistor (R5) in the boost section of the LaVache pedal from Madbeans. Its a variant of the Lovepedal Les Lius Overdrive which I believe is built upon the Electradistortion.

Here is the schematic

When the switch is open its just a huge resistor in parallel with R4 and when the switch is closed its bypassed completely.

What am I missing!?

Thanks!
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Re: Question about resistor in boost section of LaVache

Postby marshmellow » 08 Apr 2017, 13:20

C2 has very low impedance for audio frequencies, it bypasses R4 for AC signals in order to maximise the gain of the stage. With the switch open, R5 is in series with C2, so C2 is practically out of the circuit. The resistor is there to connect the second leg of the capacitor to ground, otherwise it could plop when the switch is engaged.
Last edited by marshmellow on 08 Apr 2017, 13:21, edited 1 time in total.
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Re: Question about resistor in boost section of LaVache

Postby phatt » 08 Apr 2017, 13:20

it's just there to discharge the capacitor otherwise you would get a loud pop when you close the switch. :thumbsup
Phil.
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Re: Question about resistor in boost section of LaVache

Postby fishfude » 19 Apr 2017, 15:34

Thanks for the info folks!!
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