OldSynths

Piezos cracked?
Definitely a possibility expecially if under a drum pad.
Possibly the pad needs to be a little thicker, and
maybe have a backing(another rubber pad) behind it.
i see so many piezos with the wire detached.
everyone tries to "solder" it back on..heh heh
you know, even a little piece of piezo material will
generate a voltage.  BTW, it's crystal not ceramic.
it's a property of crystals to generate a voltage when struck.
crystals can also be cut to resonate.
if U still have a piece of piezo on brass, take a wire, tin it
with solder then flatten it with a hammer.  Superglue or
epoxy this flat conductor to the top of the piezo material.
U should be able to tap it with your finger and see a spike
on a scope.  the brass is the gnd for your probe.

do like Mic Fleetwood did.
put a bunch of sensors in a shirt and play MIDI drums on your chest.

afn
tb





--- In oldsynths@yahoogroups.com, "ascii_me" <rmcdonald@w...> wrote:
> Piezo material is usually a ceramic (or crystal), so while it 
doesnt 
> technically "deterioate", lots of vibrations over time could cause 
> the piezo to become chipped or detached from the brass they were 
> mounted on.
> Rory McDonald
> Oldsynths Moderator
> 
> --- In oldsynths@yahoogroups.com, sasami@h... wrote:
> > tb22 wrote:
> > 
> > >Rubber 'does" deterioate.(maybe just needs cleaning)
> > >Piezo does not.(can crack, though)
> > 
> > You don't say. I have a couple of drum things here that use piezo 
> sensors.
> > Now they are just little brass disks - 90% of the piezo material 
> has been
> > bashed off. And yes, these were mounted UNDER the pads.
> > 
> > Ken
> > 
> 
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