Changing a pot value

[Bulinski102]

Hello everyone,
Right now I am building a firebird style guitar with onboard effects. I want to put in a tone bender style fuzz and use a stacked pot instead of two pots (I want it to look as normal as possible and already have three other controls). I have a dano-style 1m/100k pot, but I need the values to be 100k/1k. I am pretty sure that you can drop the value of the 1m to 1k by adding resistors between lugs 1 and 2 and lugs 2 and 3 of value 500 ohms. (Can someone check my math on this?)
The 100k is also supposed to be audio taper. Is it okay to use a linear taper one instead?

Here is my math:
1k/1000k+x=1k/1k
X=999k/1000k=1k=two 0.5k in series

[Govmnt_Lacky]

I am spitballing here and the TRUTH can be found at the Geofx link at the top of this page BUT....

I believe that both of the pots in question are used as variable resistors instead of voltage dividers. It is easy to modify the total resistance of a LINEAR pot used as a voltage divider but when changing a pot used as a variable resistor... you are going to change the taper or sweep on the rotation.

In the end, you can get the 1M pot down to 1K and you can change the taper of the 100K with taper resistor BUT... you may not like the sweep of the pots when you do it.

Once again, RG has a great article on "The Secret Life of Pots" on his Geofx website linked above.

[duck_arse]

and if you were going to do this, you would probably be better off shifting the 1M to 100k, and the 100k to 1k. still be wild tapers though. it might be easier [?] to mod the circuit to work with the pot value.

(only might.)

[Govmnt_Lacky]

A 110K resistor across lugs 1 & 3 of the 1M pot will get you 100Kohm

Also, a 1.1K on the 100K pot in the same manner will get you close to 1K.

YOu could always try and see if it works for you! 

[Bulinski102]

I am spitballing here and the TRUTH can be found at the Geofx link at the top of this page BUT....

I believe that both of the pots in question are used as variable resistors instead of voltage dividers. It is easy to modify the total resistance of a LINEAR pot used as a voltage divider but when changing a pot used as a variable resistor... you are going to change the taper or sweep on the rotation.

In the end, you can get the 1M pot down to 1K and you can change the taper of the 100K with taper resistor BUT... you may not like the sweep of the pots when you do it.

Once again, RG has a great article on "The Secret Life of Pots" on his Geofx website linked above.

http://fuzzcentral.ssguitar.com/mkII/mkIIlayout.gif

Here is the schematic. I am by no means an expert with these things but I think you are right. Switching the 1m to 100k and the 100k to 10k will probably be a safer bet in the end.