Re: Loopable percussion (was: Tabla...)

[Matthias Grob <matthias@grob.org>]

>hey matthias, i'm not a doctor, at least not in the proper sense ... :-)

what a pitty, mylord :-)

>> Dr. Cummings wrote:
>> >sounds like fun - i've been "attaching" piezos to cymbals with 
>plumber's
>> >putty. they also work great on kalimbas, pieces of wood ...
>>
>> Yes, serious solutions. What is "plumber's putty", please?
>
>plumber's putty is basically a gray lumpy sticky mass - maybe we should
>call it playdough for profis ;-)
>the german word for it is "Kitt" (du kommst aus der Schweiz ja?)

Ja genau!
Unfortunately Kitt has his own acoustic properties and in some way isolates
the pickup from the real vibes. It helps in case of the pickups that use a
mass on their back side to measure the vibrations against.
But I found its better to hard glue the pickup into the flow of the 
vibrations.
This may not be very easy to understand, but after talking to manufacturers
of piezo pickups, I felt that we all do not know quite so exactly what is
really going on... :-)

>> >- swallow a piezo with a vey long wire attached (don't laugh, it's been
>> >done)
>>
>> and then what, hit your belly? Listen to the stomac?
>
>legend has that the finnish band pan(a)sonic did this at a performance -
>i have no idea what it would sound like - i don't think i'll find out
>any time soon ... ;-)

I thought about installing a wireless under the skin to capture my leg
percussion...

>> >be careful not to get any between the piezo-element and the drum/cymbal
>> >surface. the key to a non-distorted sound is to have the piezo-element
>> >completely flush with the vibrating surface. the other thing you may
>> >want to consider is a preamp circuit.
>>
>> Very correct. I usually drill a 3mm whole and glue it in to make shure 
>the
>> waves pass THROUGH it. The element is blinded but as naked as possible. 
>It
>> works nice on any solid material. The preamp needs to be close because 
>so
>> far I could not find a flexible fine cable that is suficiantly blinded 
>and
>> the cable itself transmits sound waves to the pickup.

>what do you mean by "blinded" - do you mean insulated (deutsch
>"isoliert")?

Nein, "abgeschirmt". Sorry, I confused portugese "blindado" with 
"shielded".

>do you drill a 3mm hole directly into the piezo or do you drill the hole
>into the object to be amplified?

Into the object. The piezo is a ceramic material that is very hard but
breakes easily. So you have to be carefull to install it where it can
receive the pressure of the sound (like between bridge and string), but
without forcing it in other ways (like bending).
You may read more about it on my site http://matthias.grob.org where you
find some story about the PARADIS piezo pickup and the link to its patent.