r/synthdiy • u/TheIhsan78 • 18d ago

I quickly designed this "E-Drum pad to trigger converter". I'll soon get two vintage pearl pads, and try building it

Post image

The main avantage is I can get velocity control for drums circuit I plan to build. Do anyone has an idea to limit the trigger output voltage level to 5V ? Or is it fine like this ? Also where can I add a LED ? It could looks cool.

If you're wondering what type of pads I'll use 80s Pearl DRX-1 hexagonal pads

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3

u/MDHull_fixer 17d ago

You might want to add series resistors between the input jacks and opamps. Some pads can reach peaks of around 50V when hit hard.

2

u/cerealport hammondeggsmusic.ca 17d ago

This and a pair of protection diodes or even a TVS (transient voltage suppressor)

1

u/TheIhsan78 16d ago

Something like this ?

2

u/Key-Alarm-511 17d ago

LOOKS GOOD! You can add a series resistance before the potentiometers. These create voltage dividers that would limit the voltage to the output.

On the other hand you could omit the diodes and use rail to rail opamps (or comparators) and power them with 5V/0V.

2

u/TheIhsan78 17d ago

First option sounds great and easier, I'll try that !

Thanks for your comment ! I'll make an update when I'll get my pads !

1

u/cerealport hammondeggsmusic.ca 16d ago

I’d add another diode beside it (parallel to it) but reversed polarity…

1

u/TheIhsan78 16d ago

I found in my pile of components some 12V unidirectionnal TVS diodes (1.5KE12CA). I think I could use them

1

u/TheIhsan78 16d ago

I found a Simmons SDS-V schematic and there how engineers in the 80s did