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Hi . i'm new in this spice simulators. I was wonder if i can make a pot sweep simulation like Duncan Munro tonestack calculator to analise the frequencies reache by the potentiometer behavior.

Thanks anyway

I used the search box at the top of this page to search for "tone stack" and came across a public circuit by @chrisrossi:

If you open that up and run the frequency domain simulation, you'll see that it's set up to show the frequency response sweeping on parameter "R10.K" from 0 to 1 -- that's like turning the potentiometer R10 all the way from one extreme to the other.

You can then change the sweep parameter and try "R3.K" or "R5.K" to sweep the other potentiometers. You can really see how R3 affect the bass gain, and how R5 affects the treble.

Thank you mrobbins. Your program rules. =)

An example from Duncan Munro's pages ...

thank you signality. May i ask the funcion of Rsource?

A guitar pickup is not a simple ideal voltage source nor an ideal current source.

It can be represented crudely as a voltage source with a series source resistance (A Thevenin source) or as a current source with a parallel source resistance (Norton source)

http://en.wikipedia.org/wiki/Th%C3%A9venin's_theorem

http://en.wikipedia.org/wiki/Norton's_theorem

In practice, the pickup is a much more complicated source which is not modelled in the above example.

Some background to guitar pickups:

http://en.wikipedia.org/wiki/Pickup_(music_technology)

http://www.muzique.com/lab/pickups.htm

https://sites.google.com/site/distorque/home/articles/spice-humbucker-model

The above model is reproduced in CL here:

You can cut and paste the pickup model into the Duncan Munro tone stack circuit to see what effect a more complex pickup model may have.

:)

Thats informative post again. More simpel version without Eddy current: the Reddy would drop away, and 1 inductance plus Rpickup would be enough (like in the muzique link)

I'm now trying to figure out the Eddy current thing. I know the general idea behind it, but why is it modeled with a parallel resistor and why between 2 inductance poles?