VOLUME POTS: CHANGING A to B...

As I'd said in "POTENTIOMETERS: BY THE VOLUME", volume pots of the same correct value can effect a mic's output response in very different ways due to their designed-in response curves -or "TAPER". The most typical examples are "A" pots and "B" pots. Find the resistance markings on a given pot and often the designation of "A" or "B" will be present. "A" taper pots are logarithmic (sometimes called "log"), to match with our logarithmic perception of sound. Thus, "A" taper pots are commonly called AUDIO TAPER. "B" taper pots are known as LINEAR TAPER pots are their increase/decrease would graph as a straight diagonal line when used appropriately.
Above all, you want your volume pot to provide the results you expect. For lower resistance applications -say up to 100K (which includes the SHURE CM family)- the "A" pots work smoothly. However, up in the crystal and ceramic range (above 1MEG) I've found AUDIO TAPER pots tend to act more like an ON/OFF switch, either at the onset or end of its rotation. Some players will love this, sure, BUT if you're looking for smooth, even increases, I've found the higher resistance LINEAR TAPER pots are much more predictable.
What to do: Let's say your crystal-equipped harpmic currently has a 5MEG "A" pot and you find its volume curve has a very heavy 'bump' at one end of its rotation. Want to try smoothing it out? Get yourself a common resistor that's 1/10th the value of the pot (as close to 500K as possible in this case) and solder it between the two "hot" or non-grounded terminals of the pot. Wooooooo, smoooth!
THE KEY: Divide the "A" pot's resistance by 10 to find the value of the resistor that will make it behave like a LINEAR.
Clear as electric mud? Got questions? Want to know more? I'm here to help. Email or call me.