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Author Topic: Old Potentiometer markings - antilog pots?  (Read 7354 times)

Circuitbenders

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Old Potentiometer markings - antilog pots?
« on: September 16, 2010, 12:40:51 PM »

I have a studiomaster series II desk from the early 80's that i've been using for years, which has started to develop some really annoying problems on the EQ frequency pots. In their infinite wisdom stuiodmaster chose to use dual 40 click, 100K pots labelled C100K.

With the annoying click stops they actually give you 1/3 of the resolution of midi and a lot of them have started to pop and squeal like the EQ is possessed, so i'd like to replace them all with normal pots, but i can't find dual anti-log 100K miniature pots anywhere without making a special order from some manufacturer.

According to some sources i've read, C used to be the code for a log taper rather than antilog, but i'm assuming this desk isn't old enough for that to be the case.

Anyone got any ideas? I've checked all the normal suppliers.

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noiseybeast

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Re: Old Potentiometer markings - antilog pots?
« Reply #1 on: September 18, 2010, 06:34:34 AM »

Is it true that you just reverse the lug connections to get antilog as I've read in a few semi-reputable places?
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noiseybeast

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Re: Old Potentiometer markings - antilog pots?
« Reply #2 on: September 18, 2010, 06:36:48 AM »

http://www.freestompboxes.org/viewtopic.php?f=42&t=2200

For example (there are 2 opinions that both seem believable on this page)
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Circuitbenders

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Re: Old Potentiometer markings - antilog pots?
« Reply #3 on: September 27, 2010, 02:31:46 PM »

a log potentionmeter wired the other way around won't give you an antilog curve, it'll just mean the response direction will be reversed but vast majority of the pots response will be spread over about 10 % of its rotation. That is, if you had to use a log pot to give an even response in the first place.

Check out this disgram from: http://sound.westhost.com/pots.htm



what i'd like is a drop in replacement that doesn't have click stops.
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Circuitbenders

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Re: Old Potentiometer markings - antilog pots?
« Reply #4 on: October 01, 2010, 07:05:30 PM »

i think i've got this sorted. You can get dual C100K pots off ebay from a chinese seller. I haven't tested them yet to see just how 'antilog' they actually are but they're going to have to do.
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