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Re: [Doepfer_a100] Mixer: A-138a or A-138b ?

2017-02-27 by james.husted@mac.com

That is Really funny. “A” is almost universally used on pots to denote Audio Taper (exponential as in 100kA) and “B” is almost universal on pots for Linear response curves (as in 100kB). I wonder why Doepfer went with the opposite for the module names? 

Just goes to show they are exchangeable to me, I have both kinds and use them in both ways.
-James

> On Feb 27, 2017, at 10:13 AM, Diego Ragnini diegora@free.fr [Doepfer_a100] <Doepfer_a100@yahoogroups.com> wrote:
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> Yeah Christian, thanks, by the way we did realize that James inadvertently inverted the polarity… :-) 
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> Il giorno 27/feb/2017, alle ore 18:33, "christian ienni ienni23@yahoo.com <mailto:ienni23@yahoo.com> [Doepfer_a100]" <Doepfer_a100@yahoogroups.com <mailto:Doepfer_a100@yahoogroups.com>> ha scritto:
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>> "A"s are linear, "B"s are exponential  ;-)
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>> From: "james.husted@mac.com <mailto:james.husted@mac.com> [Doepfer_a100]" <Doepfer_a100@yahoogroups.com <mailto:Doepfer_a100@yahoogroups.com>>
>> To: Doepfer_a100@yahoogroups.com <mailto:Doepfer_a100@yahoogroups.com> 
>> Sent: Sunday, February 26, 2017 11:34 AM
>> Subject: Re: [Doepfer_a100] Mixer: A-138a or A-138b ?
>> 
>>  
>> Both the A and B versions will work for both audio and control voltage uses, the only difference will be in how the knobs “feel” when you turn them. The A has Audio Taper pots which make audio sound louder in a more familiar way as you turn the pots, the Linear Taper pots in the B versions will not get louder in the same way, with the same turning distances for instance, but will still mix audio signals. If you mix by ear and not knob positions, there won’t be any difference between them. The A version is not Audio Coupled (having caps in the audio line to stop DC), at least mine don’t and I don’t even know which ones I’m using when I use them. 
>> 
>> Oh, and they both have the normalized DC voltage on input #1, allowing a DC offset voltage to be added to the mix if #1 does not have a cable plugged into it. At least the ones made after 2004 anyway.
>> -James
>> James Husted, Designer, Synthwerks LLC • www.synthwerks.com <http://www.synthwerks.com/> • james@synthwerks.com <mailto:james@synthwerks.com> • info@synthwerks.com <mailto:info@synthwerks.com>
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