Crash Sync / Bandwrecker

[bean]

I started drawing up a layout for Mark's deluxe version for 125B with top or side mounted jacks.

I'm considering one change, though. Rather than have the "Sense" pot be a variable resistor, make it a volume control inserted b/w C14 and D3. This would allow you to turn off the envelope completely when using it to dynamically control the Rate for the LFO. I think it will work fine since it's basically the same control I used for the "Glitchee" project on my website.

What do you guys think?

Here's the progress so far.

[Mark Hammer]

Makes sense to me. (no pun intended  )  You don't want fluctuations in the sweep rate when you don't want them.

I am humbled by the speed with which you can turn my hairbrained idea into a workable layout.  All hail the bean!

[bean]

Please, haha. I've been wanting to add some kind of envelope control to this project for a while so your contribution is prescient. It's my pleasure to put it through the final stretch.

I'll get it finalized over the weekend and get the new project doc up.

[bean]

Had to etch some faceplates anyway so I decided to etch this board as well. I'll go ahead and build it up first to check everything out and then put the doc up later this week.

I thought after the fact it would be cool to include an expression pedal input for the Frequency pot. I should be able to kludge it with the etched board then add the extra pads for the final one.

[Mark Hammer]

Is the expression pedal intended to replace the Frequency pot directly, or intended to directly vary the brightness of the LED?

[bean]

Is the expression pedal intended to replace the Frequency pot directly, or intended to directly vary the brightness of the LED?

I was thinking of just wiring it as a TS control directly in parallel with the freq pot. But, I can think of a few ways it could be done. It wouldn't be too hard to have the LFO disconnect when an expression pedal is plugged in and have that drive the LED brightness. Or, maybe having the LFO and expression pedal at the same time would produce some interesting effects.

[Mark Hammer]

I doubt it could be implemented via a simple T-S jack/plug, since the Frequency pot is not a simple resistance-to-ground.  I mean, you could use a plastic T-S jack, with no ground connection, but I think that requires too much understanding on the part of the end user, with respect to what expression pedals are usable.  As much fun as it might be, here I think it best to leave a fairly simple circuit as uncomplicated as it can be.  I think we've pretty much topped out what is easily done by an average builder/user.

[moosapotamus]

Would a pot instead of a switch between LFO and Envelope control work?  I think a blend of the two would sound cool.  For example, full CCW for LFO only, full CW for envelope only, and a blend in between.  Envelope control with an expression pedal for frequency at the same time would probably be pretty fun, too!  If you don't want either, I assume you can just turn the depth all the way down.