Parallel Universe starve circuit question...

[digi2t]

Hi all,

I'm planning on building a Parallel Universe (version 2), and I noticed that the original PU (V1) also had a 1k pot in addition to the 2k2 resistor to vary the starve voltage. I was wondering if I could do away with the 2k2 resistor, and just run a 5k pot as my starve circuit, would that work? I imagine that it would be a bit more flexible sound-wise, but has anyone tried this?

Thanks,
Dino

[emstin1]

I think the resistor was there so that the pot never went to 0 resistance, making it so there was always some power making it's way to the circuit. 

[digi2t]

I'm not too sure of that... on the V2 schematic the starve function is either on or off. The 386 pin is fed either +9vdc direct or the reduced voltage from the 2k2 resistor. That's why I'm thinking of nixing the 2k2 for the b5k pot to make it variable.

Here is the old PU;

http://www.experimentalistsanonymous.com/diy/Schematics/Fuzz%20and%20Fuzzy%20Noisemakers/Parallel%20Universe%20Schematic%20(old).gif

And here is the new one;

http://www.experimentalistsanonymous.com/diy/Schematics/Fuzz%20and%20Fuzzy%20Noisemakers/Parallel%20Universe%20Schematic.gif

The old one went to 0 resistance when you chose to go through the pot. The new one goes to 0 when you kill the starve function. I'm convinced that simply running through a 5k linear will allow me to find "sweet spots" in between. No?...... Maybe?.......

[PRR]

> just run a 5k pot

Yes.

You may find that anything over 3K or 4K is "starved to death"... that supply voltage at the LM386 gets so low that the LM386 won't pass signal. No disaster, but that may be why the original values are what they are.

[digi2t]

Thanks PRR. You're probably right, at 5k I probably will starve it to death. But, the idea is to just have a bit more flexibility insofar as the starve resistance is concerned. Just to experiment with the zone inbetween 0 and 3.3k, as the version 1 PU allowed. I figure if it works well enough, I'll put a graduated knob on it (as I did for my Uglyface LFO speed) and keep track of the settings when something interesting pops up.

Thanks all.

Cheers,
Dino

[digi2t]

Thanks for your input guys. Just finished the build, and it's mucho nice with a 5k pot. I tried a 2k as well, but I couldn't get quite as low as I wanted. You get a little past 1/2 way with the 5k before you kill it though. I guess a resistor bridge on the pot could fine tune that a bit more, but I can live with it.

Thanks again,
Dino

[jacobyjd]

Thanks for your input guys. Just finished the build, and it's mucho nice with a 5k pot. I tried a 2k as well, but I couldn't get quite as low as I wanted. You get a little past 1/2 way with the 5k before you kill it though. I guess a resistor bridge on the pot could fine tune that a bit more, but I can live with it.

Thanks again,
Dino

I'm pretty sure that's why Colin redesigned the starve control in Version 2--there wasn't a whole lot of usable adjustability to be had.

[digi2t]

Thanks for your input guys. Just finished the build, and it's mucho nice with a 5k pot. I tried a 2k as well, but I couldn't get quite as low as I wanted. You get a little past 1/2 way with the 5k before you kill it though. I guess a resistor bridge on the pot could fine tune that a bit more, but I can live with it.

Thanks again,
Dino

I'm pretty sure that's why Colin redesigned the starve control in Version 2--there wasn't a whole lot of usable adjustability to be had.

Well, I wouldn't throw that baby out with the bath water. I've been playing with it for a couple of days now, and I find that being able to tweak the resistance is great for getting jumping octave sounds, as well as down right sputtering. It's a niffty pedal to have in the arsenal.

Cheers,
Dino