[LAU] setBfree: Gain sweller from lin to log characteristic

Will Godfrey willgodfrey at musically.me.uk
Wed Dec 15 09:31:41 CET 2021

On Wed, 15 Dec 2021 02:06:19 +0100
Robin Gareus <robin at gareus.org> wrote:

>On 12/14/21 11:02 PM, Gerhard Zintel wrote:
>> Now I have the following questions:
>> Does anyone of you know if the original swell pedal of the B3 is 
>> changing the volume in a linear or logarithmic way?   
>Neither, and it is complicated.
>Since the gain is applied before the pre-amp, many refurbished B3s use a
>lamp and photo-cell/resistor to reduce hum, so any mapping is possible
Exactly! That was very common with a lot of 'portable' electronic organs of
the 1960s too, and a bit of a nightmare. There was quite a wide range in
photocell responses, along with changing output from the bulb depending on age
and supply stability.

Will J Godfrey
Say you have a poem and I have a tune.
Exchange them and we can both have a poem, a tune, and a song.

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