[sdiy] Dual-gang reverse-log pot group buy ?

Andre Majorel aym-htnys at teaser.fr
Mon Nov 17 14:44:50 CET 2008

Regarding the recent talk of a group buy of Alpha pots...

Parametric equalisers often use anti-log pots for the frequency
control. Would anybody be interested ?

If Kevin orders direct from Alpha, minimum order is one thousand
of each reference, meaning we'll be lucky to reach MOQ for *one*
value. Here's what the circuits I've seen use :

  Moog 3-band http://files.muziq.be/schematics/moog_pareq.jpg :
    100 k dual for each band

  Rane PE 15 http://rane.com/pdf/old/pe15sch.pdf :
    100 k dual ("100KE" antilog assumed)

  Rane PE 17 http://rane.com/pdf/old/pe17sch1.pdf :
    100 k dual ("100KE" antilog assumed)

  Speck ASC http://www.speck.com/asc/asc_2.shtml :
    500 k single for the low band (simulated inductor, peak/shelf)
     50 k dual   for each mid band
    500 k single for the high band (simulated inductor, peak)

  Ethan Winer's SVF http://www.ethanwiner.com/spect-1.gif :
     50 k dual   for each band (SVF)

What would be the best value ? 50 k ? 100 k ?

Don't know how much duals cost but the prices Alpha have quoted
for singles are pretty good (0.22 USD). At that kind of price, you
wouldn't need to stock both singles and duals...

No promises, though. This is Kevin's group buy, it's his decision !

André Majorel <URL:http://www.teaser.fr/~amajorel/>

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