Series or Parallel Gain Control at the Front of a Circuit?

[Blackbeard]

Hello All,

I am in the midst of building a Jordan Bosstone and stopped myself when I got to the "Attack" control. I know this circuit will likely have lousy input impedance and I know that a higher input impedance is usually better. My question is this, will putting the Attack control in series with the input have any different effect on the impedance? Sound?

Here is a crude diagram below to show what I mean. The one on the left is the original Attack control, which if I'm not mistaken, acts like a voltage divider ? The series resistance would be like using your guitar's volume knob right?

3
l                                                                   2------
>2--------Input Cap           VS            __3_/\/\/\__1__Input Cap
l
1

Thanks in advance everybody!

[GGBB]

A guitar's volume control is also a voltage divider.  A pot acting as a series resistor will not do the same thing, although it will affect the input level as it is turned down (increasing resistance) and other aspects of the sound since it does increase the input impedance.  Try both and see what you like.  You could even add a toggle switch to move the pot's lug 1 from ground to lug 2 so that you can switch between the two modes.

[Kesh]

The right hand's effect depends on the impedance the comes after it.

Basically, if you don't have a lug to ground like you do on the left hand pic, then you still have something else going to ground coming after, and that forms the lower part of the voltage divider instead of the lower half of the pot.