Insanity Box success !!! and resistor switch question.

[syzygy]

I have just completed building the Insanity Box circuit.  At first it didn't work, due to me using a dual opamp in a layout that required a tl071 style opamp. So I replaced it, and wham-o!  A feast for my ears!  With the PCB layout, it wasn't a difficult build at all -- although I had to accommodate for different pinout of my J201s, and I noticed a resistor and cap were swapped in the layout, which probably won't affect anything, and I had to extend one of the leads on each of my trimmers to fit the different sized ones in the PCB.  So other than double checking the schematic on these slight differences, it still works like a charm.  The layout could be made even more easier by adding a diagram for wiring the pots.

Anyway after 2 hours of turning the trimmers in different combinations, I picked out several different sounds I liked, and I won't be satisfied with only one sound when I put this thing in an enclosure..

So... does anyone have any experience or comments switching out several different resistors in place of the 100k trimmers in this circuit to switch between my favorite resistance settings?  It would be nice to use a 3 way toggle switch for each node..  Do you think I'll have trouble with popping?

thanks!

[mongo]

where I can see this projet's  PCB??


Thanx!

Andy

[syzygy]

Go here and scroll down to "Insanity Box".  You will see the PCB there and the press and peel layout.

[Skidood]

Yes, you probably will get popping, or worse, as it apears you will be opening up the feedback path on op-amps while switching...no problem if you do it while the effect is bypassed of course

[syzygy]

Yes, you probably will get popping, or worse, as it apears you will be opening up the feedback path on op-amps while switching

I have read in the FAQ of ways to reduce clicking and popping when stomping the bypass switch or switching capacitors.  Does the same thing apply here with switching resistors?  (solution: adding a pulldown resistor? where would you add it?)

[Skidood]

No, I don't think so, because you'll be adding signal  paths to ground in the middle of the circuit by doing this. It will mess up the circuit.

[aron]

Do you think I'll have trouble with popping?

Do it this way. Use resistors in parallel to obtain your desired settings.

So put the trimmer at the max value (setting) that you want. Then use the switch to put another resistor in parallel to get the new (lower) value.

use this formula:

For 2 values: RT = (R1 X R2 )/ (R1 + R2)

So one setting is the trimmer by itself, the next with a resistor in parallel with the trimmer. Then perhaps another setting is an even smaller resistor in parallel with the trimmer. etc...

[syzygy]

aron,

That is a great idea!  It doesn't sound like I will get any popping that way, is that right?  ..since I won't be breaking the circuit, just breaking one resistor.

Anyway this is a great sounding circuit to me.  it has the ability to be modified  in several different ways, so it will probably be the most exciting to finish with added mods.

By the way, the first 4049UBEY I used worked fine.  One question about the purpose of putting the FET Minibooster in there -- was the intent to have the ability to crank up the level, or was it to change the distortion character?  To my knowledge a booster just amplifies, it doesn't mess with the sound signature, but I could be wrong... ?