Gate to trigger idea

[StephenGiles]

http://electro-music.com/forum/viewtopic.php?t=66526&sid=c73aee4839579b4597d27b74f3326dbb

Could be useful for triggered auto filters and the like. 

[Kipper4]

Thanks for sharing Stephen.
Saved a copy, I'm sure it will come in handy in the future.
Cheers
Rich

[atwas2112]

That should work with a 40106 instead of a 4050, right?

[bluebunny]

40106 is an inverter (Schmitt).  4050 is a buffer.

[anotherjim]

You'd need to test, but if you wanted to use Schmitt trigger devices, adding R1 & R2 might over-ride the chips own input thresholds for similar results. If your device is inverting, 2 of them in series with R1 from input to final output as if it was a single non-inverting device - it must be a non-inverting function for this to work.
If you leave it to a Schmitt trigger devices own thresholds, it might be ok at that. you wouldn't need R1, but I would still fit an R2 to limit current in the devices input protection diodes because C1 will place a negative voltage on the input when the gate goes low.
In synth world,  the Gate is a "key down" or "note-on" control - it's high as long as the key is pressed. Translating to guitar, given an envelope follower, a comparator that provides a high output when the envelope is high enough to signal a "note-on" would be the Gate control. Given a good match between the trigger thresholds and the envelope followers amplitude, the envelope itself could be the gate. You can manipulate the thresholds by changing the relative values of R1 & R2.
The short trigger pulse should only occur at the moment the gate goes high. Trigger starts an envelope shapers Attack phase.  The point of it would be to give you an artificial sweep that has little to do with the real envelope.

[StephenGiles]

The short trigger pulse should only occur at the moment the gate goes high. Trigger starts an envelope shapers Attack phase.  The point of it would be to give you an artificial sweep that has little to do with the real envelope.

Think about it - "an artificial sweep that has little to do with the real envelope." For that read EH Space Drum envelope generator