[font=trebuchet ms]Other than a few minor misconceptions, that's very good advice.[/font]

Originally Posted by: fastelvisPony - Check your wiring - a 1 meg pot should shut off anything. Check it with an Ohmmeter to be sure it's really 1 meg. Also, if a load resistor is used (read below) check its value. These can vary a lot in value.[/QUOTE][font=trebuchet ms]Actually, any value of pot should shut off completely at full CCW. In this position, the moving contact (the 'wiper') is connected to ground, or [u]should[/u] be.[/font]

Originally Posted by: fastelvisChanging pot values changes the "amplitude" of the pickup's peak frequency across the tonal spectrum. This is often called "sparkle" or "quack" with single coils or like Pony calls "bark" on his humbi.[/QUOTE][font=trebuchet ms]This is a bit unclear. The pickup is a signal source. The frequency content of the output signal changes according to the circuit conditions. The qualities called 'sparkle', 'bark', or sometimes 'openness' or 'detail' are the result of uper-mid and high frequency content. Lower frequencies are not significantly affected by volume pot impedance. Much of the frequency spectrum remains the same.[/font]

Originally Posted by: fastelvisA 1 meg pot loads the circuit more and allows the pickup to jump to the peak frequency faster. Smaller value pots spread it out or "tame" it.

[font=trebuchet ms]A higher resistance value imposes [u]less[/u] of a load on the pickup, particularly at the higher frequencies that determine a lot of the perceived tonal character of the sound. 'Attack' is a function of how quickly the 'envelope' of the signal amplitude goes from zero to max. A muddy tone may have a very fast rise in amplitude, but a tone with more treble content will sound like it has more attack, even if the envelope is identical.[/font]

[QUOTE=fastelvis]You can drop a resistor between the input and output of lugs on the volume pot to make the pickup think there is a smaller value pot. This will tame the pickup more. Experiment with 50k, 100k and 150k 1/2 watt resistors for humbuckers guitars loaded with 500K pots....

... You might want to install a 0.001µF (microfarad) capacitor in parallel with the resistor or trim pot as a treble bleed circuit to retain the highs when you roll off the volume. All my humbi loaded guitars have this.

[font=trebuchet ms]A resistor connected from the wiper contact to the CW contact will have no effect at the CW (up full) position, because it is shorted out. As the control is moved away from this position (turned down), the low value of this resistor is seen to be in parallel with the 'upper' portion of the pot between the wiper and the CW contact. With the values given, this would result in the ability to make finer adjustments in volume at the top end of the rotation, but would drastically roll off the high-frequency content of the signal, making it sound very 'muddy' at less than full volume. This makes the additional capacitor for 'treble bleed' necessary.[/font]

[QUOTE=fastelvis]Here on some tips on pots.

1. Don't buy cheap pots. Personally, I see nothing at Stewmac that resembles a quality volume pot and the majority of guitars on the market are loaded with crap electronics. Check with your local high-end electronics store (Radio Shack DOES NOT qualify). Pick out a good, sealed, plastic composite or wire wound, audio (logrithmic) taper pot. Have them check the values with an Ohmmeter right there. Make sure it is zero at full CW and very close to the rated value at full CCW. These high quality types will often have a rectangular case with small lugs a metal tab for ground. Overheating pots can ruin them. If you do not know the correct way to solder, have someone else install them. These will last a long time, are very smooth and very, very quiet. They will never need cleaning. Take your old one in with you to be sure you get the correct shaft/collar length.

[font=trebuchet ms]Yes!!

You should look for plastic composite or cermet (ceramic/metalic) element pots. The good ones are fully sealed, so they don't get dust in the works, and they are inteded to function at spec over many thousands of operations - much more than most guitars are ever likely to see. An audio-taper pot should show 10% of the total resistance measured from the wiper contact to the CCW contact at mid-rotation. Good manufacturers are CTS, Bourns, and Mu-Rata.[/font]