Pot values

[mr.adambeck]

I'm sure this is pretty basic, but I'm having touble finding an answer on the net.  What exactly do pot values mean?  For example, what is happening when I change from a 100k to a 500k, etc?  How does it affect the audio and why?

Thanks

[BAARON]

How does it affect the audio circuit?  It depends on the application it's being used in.  There's no single answer.

The value of the pot is the resistance between the outer two lugs.  The middle lug is just attached to a "wiper" that slides around the resistive band, giving you access to connections in the middle of the resistor between the outer lugs.

[Top Top]

Just to elaborate and clarify on this, the pot will range generally from 0Ω to whatever the value of the pot is... ie: a 500kΩ pot will give you resistance values from 0Ω to 500kΩ.

It functions the same as any other resistor in a circuit does, with the difference that the value is variable. Depending on where it is placed in a circuit and the design, it could be volume output, drive level, speed of an effect, sensitivity, and on and on.

Generally any control that you see on an effect controlled by a knob uses a pot, and the reasons for the values of the pot have to do with the application of the resistor within the design of circuit.

[mr.adambeck]

So it you have a pot that is essentially blending between two signals, is it still working as a resistor?

[BAARON]

If I understand what you're asking, it's like there are two resistors: one from the left lug to the middle, and one from the right lug to the middle.  Turning the pot changes the position of the wiper (attached to the middle lug), and therefore the value of the two resistors.

But yes, potentiometers are resistors.

[norbizzle2012]

Im not sure but i think they can also be used as a voltage divider by connecting one of the outer lugs to ground and the other to a positive supply and the middle will give you a different voltage depending on how much you rotate, correct me if im wrong.

[BAARON]

Yyyes, you can use them that way, but you won't have much current at that middle lug.

Any two resistors in series form a voltage divider.  Because a potentiometer acts like it has two resistors in series with the middle lug (wiper) between them, it acts like a variable voltage divider.  That's how most volume controls work, for example.  http://en.wikipedia.org/wiki/Voltage_divider