How to choose pots?

[kristoffereide]

When cooking my own effects, how do I choose which resistance pots to use?
And what would happen if I use a 10k instead of a 25k or 50k pot?

[punkin]

For me...when breadboarding and experimenting...I use wide range pots...big numbers. Later, after the circuit is finalized, I look at the "useable range" and get something that fits. After the circuit is finalized, I put an ohm meter across the pot and sweep the "useable range and order something close".

[kristoffereide]

ok thanks! So what happens if I replace a pot with another of less ohms is I narrow the field of tuning?

[punkin]

Well...the idea is to select a pot that provides a useable range to the effect. If you use something too wide, only a narrow range in the middle may be pleasing. The upper and or lower range useless. Suppose a tone pot...when you get down low to the bottom of the useable/audible range, nothing is gained but the pot may continue to turn. That's about it I think. From a user standpoint, you want a pot that has affect on the control from the left to the right of the pot...not just a little narrow range in the middle. Again, for breadboarding and testing I have several wide range pots. When I know what's useable, I order accordingly for the final circuit.

[kristoffereide]

again good sir, thanks.

But in the replacement-issue, I thought about replacing a pot in an already existing circuit.
I have about a billion 100k and 10k, but this circuit requires a 50k and a 25k.
Will I only be able to tune (100k) only on a small range on the pot, or (10k) only on a small range of the tone etc?

Can I in any way insert a resistor to a pot-leg and change the pot-value? 

[ollie]

Put the resistor in parallel with the pot i.e. solder them between the lugs that are connected to the circuit. When in parallel, the overall resistance is always smaller than the smallest resistor.

[kristoffereide]

awesome! thank you for all the answers guys!

[MohiZ]

I'm going to paste the same links I posted in an earlier topic about a similar issue.

This article is very informative and well written:
http://gaussmarkov.net/wordpress/parts/resistors/resistors-6-mods/

This calculator will be a handy help for you:
http://www.diystompboxes.com/analogalchemy/emh/emh.html (choose linear pot or tapered pot from the menu)

I just breadboarded an IC into my heel by accidentially stepping on one  ouch

[kristoffereide]

Thank you so much! Good reading! Sorry about your heel man, I soldered my ass the other day... and my beloved chair, at the same time! The cable to the soldering iron, should be rubber and not plastic. It has to much material memory... Fell on my chair while I was reaching for some part on a shelf.. ouch

[Solidhex]

Yo

  You should make note that when using a pot at the end of a circuit as a volume control the value of the pot interacts with your output capacitor and creates a high pass filter. Choosing a lower value pot in this position will make for a brighter sound.

--Brad

[kristoffereide]

yes, I read this in the gaussmarkov article.

Thanks though