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Pots for Tele w HB and stack

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9/15/1999 10:53 PM
David P	Pots for Tele w HB and stack I have modded an Am Std tele with a Ducan '59 in the neck and a Duncan vintage stack in the bridge. I have left the stock vol and (TBX)tone pots in it for now, but wonder if I should at least move to a 500K pot for the volume. Is there a "sweet spot" for pot values with this HB/stack configuration?

9/16/1999 4:32 PM

You may notice a slight increase in highs with the larger value pot. Most multiple coil pickups have higher inductance than simple single coil pickups. Single coil pickups sound way too bright, or even shrill, with pot values larger than 250k. They need to be loaded down a little to cut the edge. Most HB pickups use a 500k (sometimes higher) to help reduce the inherent high end rolloff effect of the higher winding inductance. Does SD recommend a 500k pot for best overall results with their pickup?

There was a time (I think when CBS owned Fender) when they were manufacturing telecaster guitars (sigle coils) with 1megohm volume pots. Talk about bright!! Do you like how it sounds now? If so, don't bother changing it. If you think you could use just a tiny bit more brilliance, then try the 500k pot. Actually, the pots are very easy to change in a tele. Another neat accessory is to use a TBX tone pot, or a DeltaTone pot for decreased loading and a clearer high end. (Your Am Std may have come from the factory with one of these special tone pots.)

Sorry for the rambling. You may be looking for a direct yes or no answer.

9/27/1999 8:28 PM
anonymous	Doc: I did post a question to the SD user group and a rep and they said to go with 300K pots for the combo. Hmm, when I told this to a local tech, he immediately responded "all 250K pots are really 300K anyhow"!! Anyone know of a source for such a beast?? SD did say that these are hard to find...

9/27/1999 8:50 PM

There is always the outside chance that a pot spec'd at 250K +/-20% falls within the specs of a +/-20% 300K pot, but I doubt whether you want to keep ordering them until you hit on one. My own experience, though, is that pots are more often likely to be UNDER the spec'd value than OVER it.

If you feel there is something magic about 300K of loading, AND you are one of those folks who rarely turn the volume down all the way, howzabout just sticking a fixed resistor between the ground lug of a 250k pot and ground? Given that you're looking at an estimated fixed resistor of 43K-68K (given the usual variation in values for pots) that still leaves plenty of potential range in volume settings, and a minimum setting that should be relatively quiet (e.g., 250k/47k is lots of attenuation), and possibly quiet enough for pinky volume swells.

Again, remember that the amp generally doesn't care where the loading comes from (pot, fixed resistor, coil, etc.), merely that when the input to the next stage can come from multiple cources (including its own input impedance) the guitar impedance have a certain relationship to that of the next stage. Unless I'm WAYYYYY off, 300k is 300k is 300k.

9/28/1999 7:34 PM

You're right, Mark. Gibson has some pots in their Les Paul guitars that are rated at 300k (or 350k?). I haven't come across a "strat-type" 250k pot that measured higher than 274k.

You could add a 47k series resistor between the bottom leg of a 250k pot & ground to get appx. 300k loading. It would never turn completely "off", but who cares. It'll turn down low enough.

The other alternative, if you must have a 300k pot, would be to buy a gibson-type pot with longer threaded bushing (needed to go through some thickness of body wood), and choke up on it with backup nut/washers to mount it deeper in a plastic pickguard.

9/17/1999 1:32 PM

An alternative is to go with the 500k, and stick a small value cap (<1500pf) between the two outside lugs of the volume pot to "tame" the high end. I have home wound single-coils and 500k pots to keep the brightness (I like the insect noises), but my tone control is a simple toggle that selects between a 1500cap to ground, nothing, and a.01 cap to ground. The 1500pf cap rounds off the edges nicely, while keeping the bite. I generally play with it set in this position, and only defeat it when I want mucho bite.

9/28/1999 11:11 PM

Let me share an idea of mine which I thought was brilliant. Although I could never get anyone else to try it, c'est la vie. I wired a HB/stack tele with a TPDT switch (thats triple pole or four pole if you can't find a triple, they come in mini's). I wired the HB for series/Parallel and the Stack for single/HB. So the combos are: HB in series with stack in single coil mode (this is the loudest/raw sound, think Keith Richards), the second position is HB in parallel and single coil in HB stack mode (this is a more even response,completly hum free, better with effects, etc.)
Give it a try if you think it will work for you. pg

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