Grateful Dead Music Forum

A place to talk about the music of the Grateful Dead 

 #157257  by GeneralGoldilocks
 Fri Jun 30, 2017 10:38 pm
Hey all, just built my first jerry caster with a troy post body, wald buffer, and david allen voodoo 69's, warmoth neck, no obel. I used a 25K "audio taper" pot off of ebay, but the volume drops out severely to almost nothing after about a quarter turn of the pot. Did I get the wrong pot? I couldn't find any logarithmic taper 25k pots, if anyone knows of any good ones, let me know! I'll try to attach a pic so you all can check it out in a bit. It is an awesome guitar and sounds great! Thanks for all the help, this page is a huge resource and I couldn't have done it without you all!
Last edited by GeneralGoldilocks on Fri Jun 30, 2017 11:19 pm, edited 1 time in total.
 #157259  by ac4468
 Sat Jul 01, 2017 4:34 am
Audio Taper and Log taper are the same. Check your pot and/ or wiring. It's possible you got a linear pot. Outside of the mil spec pots (Leo might still sell them) CTS makes a long shaft 25k audio taper pot. Alpha makes short shaft ones as well in mini or regular size.
 #157263  by GeneralGoldilocks
 Sat Jul 01, 2017 8:24 am
thats what i thought. i tried to install a dpdt mini on on switch to bypass the active circuit in case the battery goes dead and the active circuit worked, but with the wrong taper, but the passive makes no noise. i am wondering if a long wire run could attenuate the signal from the 5 way switch to the wald preamp? it is a longer run in the cavity, but shouldn't make that much difference. I also unsoldered the dpdt and go straight to the preamp now, but still with a good 3 or 4 inches of braided shielded cable.
 #157276  by waldo041
 Sun Jul 02, 2017 10:31 am
You are not really telling us all of your wiring. Your first post says the 25k does not work, then in you last post you are saying that you installed a switch to bypass the active circuitry. Does the 25k pot work with the active circuitry? It will not work with the passive circuitry, your missing a piece to get both the active and passive circuit to work independent of each other. You need a dual 25k log/ 500k or 250k log volume pot and need to wire it accordingly.

 #157282  by mgbills
 Sun Jul 02, 2017 1:13 pm
25k Log pots can be difficult to find. I personally haven't found RAV/Mil-spec other than combing eBay auctions.

Alpha makes one that is widely available. Recently I found them at WD Music. This is a standard 3/8" thread & came with resistance tolerance better than shown on the site.

Always looking for a steady supply of Mil-spec.