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Where to get G&L 1M reverse log pots?


 
11/13/2005 1:04 AM
Chris/CMW amps
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Where to get G&L 1M reverse log pots?
Hi all  
 
Yesterday a customer did bring his G&L Legacy (Strat style guitar) when picking up his modified '59 Bassman Ltd.  
That guitar does have a volume-control, a treble-control (mastertone) and a bass-control (cap across 1M rev. log pot). The range of the controls was pretty good so I wanna try this circuit in one of my Strats just for fun.  
Anyone knows where to get a quality 1M rev. log pot with a "guitar-knob-style-shaft"?  
 
Many tia!  
 
Chris
 
11/13/2005 3:55 AM
Chris/CMW amps
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found this but...
http://www.glguitars.com/shopping/shopdisplayproducts.asp?id=4&cat=Electronic%20Parts  
 
The type (log, rev, whatever :)) isn't specified.  
 
Chris
 
 
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11/18/2005 7:09 PM
Steve A.
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Chris:  
 
    I really doubt that the pot in the link would be reverse audio. There's a 60% chance that it would be audio taper and a 40% chance that it would be linear taper- at least that is the odds in Vegas. :)  
 
    For a reverse audio taper you can always use a regular audio taper pot and wire it backwards; the rotation would be reversed but you'd set it to 0 to simulate 10 and vice versa. You might compare this to a linear pot to decide if you really need to get a RA pot.  
 
Steve Ahola
 
11/19/2005 3:27 AM
Chris/CMW amps
email

Hi Steve  
 
I did check some G&L wiring diagrams and the ones with the bass-control did show "R" on a couple and "1M reverse audio" on one.  
I've tried comparable circuits in amps and the reverse log did give the nicest range/"adjustment feel". Anyway: I really did like the working of the controls in that G&L Legacy.  
 
Back to a HotRod Deville.... :)  
 
Chris
 
11/20/2005 11:12 AM
Steve A.
email

Chris:  
 
    Here are some links I found for reverse audio pots (the Weber ones are the closest but they evidently have a rotary off switch on them):  
 
http://www.guitarelectronics.com/product/CPC500R  
 
https://weberspeakerscom.secure.powweb.com/store/potsord.htm  
 
http://www.state-elec.com/ModularPots2.asp  
 
    So is this the circuit that you are talking about?  
 
http://www.glguitars.com/schematics/Legacy_schematic_blockdiagram.pdf  
 
Steve Ahola
 
11/20/2005 4:24 PM
Chris/CMW amps
email

Hi Steve  
 
Many thanks! Hope it's possible to order "a couple" from G&L ($5/each).  
And yes, that's the diagram. Maybe it's also because of the used pickups but the adjustment-ranges of all pots were just excellent.  
 
All Weber pots I did use did have "amplifier-knob-shaft, just looking for such pot that can be used with Strat-knobs.  
 
Again: thanks!  
 
Chris
 
11/21/2005 9:46 AM
Steve A.
email
D'oh!
Chris:  
 
    I should have noticed this earlier, but... the bass pot is wired as a variable resistor, not a potentiometer (2 wires as opposed to 3). I believe that if you wire up the "top half" of a 1M audio taper pot, you will get the reverse audio taper. (Normally you would connect a tone control to the "bottom half"- the wiper and the CCW terminal- the terminal normally grounded on a volume control.)  
 
    However, I do suspect that G&L might be using a special taper for the bass pot- not just reverse audio but something different than a typical 10% taper. If you still have the guitar around maybe you can unsolder one of the terminals and then write down the ohms for each position from 0 to 10.  
 
Steve Ahola
 
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