negative half-wave no hotspot?!

[talrusher]

i converted my pads by myself and tried a couple of triggering things...

i found out, that if my piezo produced a negative half-wave i had no hotspot like on positive wave.... but why?

regards

[Sylv1co]

My two cents :

I think the module wait for the first positive half-wave to trigger a note.
If your first half-wave is negative it seems that when the head is pressed (by the hit of a stick), you have a negative half-wave, then when the head returns, you get the first positive wave. The foam under the piezo may absorb some energy and then the first positive half-wave is maybe less strong than the first negative half-wave.
I don't really know at which frequency a drum head could vibrate but at 500Hz, it take 2ms to get an entire wave, so if your module have to wait for the first positive half-wave, then it will wait for 1ms.

[talrusher]

noticed that roland uses in their pads or cymbals the negative halfwave. in my cy-5 the piezo is wired to produce a negative half wave, and thats produces on the trigger io less hotspotting, but what is with the megadrum?
should i wire my piezos that a negative or positive half wave come first? what is better for the megadrum module?

[Maylord.war]

If you put your cone/piezo on one side of the pad the hotspot disappear.

Btw you can decrease the distance of Foam cone from the mesh head, 0.8 - 1mm are good, in my pad i don't have any hotspot, i use the normal configuration (positive wire) .

Try to raise the Minscan value to 45-55 ( in my 12" tom works perfect ) , if you don't need the positional sensing use the negative wire to tip e positive to sleeve.

I use a similar roland cone with 35mm piezo, for better results i add in series a 10k resistor to "cold" the signals

Regards

[talrusher]

one 10k resistor? for my 35mm piezos i Need Minimum 200k and for my 27mm at least 159k...

can u make some Pictures of how do you mounted the piezo exactly to your pads? or describe it exactly plz...

[Maylord.war]

Hi Talusher

Sorry for the late reply.

Actually i don't have any pictures to show you how the cone is fitted.

Are you sure you need 200k resistor?

I mean 10k single resistor , perhaps you mean a 200k potentiometer ?

Wich "highlvl" and "gain" value do you have?