Re: Percussive dance sensors - request for any information

Mark Coniglio (troika@panix.com)
Tue, 1 Jun 1999 16:51:18 -0400

>My ideal would be to develop a complete instrument - a floor based
>'drum-pad' large enough to be divided into zones much as the steel-pan drums
>used in steel-bands.

What you need is an Alesis D4 (available for about $200 on the net) which
is a MIDI Drum machine that has the added feature of 12 inputs to which
MIDI Drum Pads can be connected. The sensors are simple piezo disks, which
can be bought at Radio Shack or an electronics supply store for $1-$2
each.I can look up a part number if you need it. Connect the leads to a
1/4" phone plug, plug it into the D4, and voila: your own drum pad. Of
course, it is a little more complicated than that because the piezo's are
brittle -- you will need to cover them with something.

>Particular questions:
>a) Has anyone done this already? They appeared to use a sequence of five(?)
>mats in 'Tap Dogs', each one triggering a single drum sample, leads for
>further info?

We have used this technology in one of the pieces I created for our company
Troika Ranch. There are two set pieces, each with two sensors each. When
the dancers move about on these set pieces, video and audio events are
triggered. The bit from Tap Dogs was almost certainly done the way I have
described above.

>b) There was a sequence at the end of the film 'Tap' starring Gregory Hinds
>where the sensors were built into the shoes and the sound was then altered
>at a sound-desk. Unfortunately, I believe this was just the magic of
>cinema, does anyone know?

The shoes were designed by Alfred Desio. He calls them Zapped Taps. Search
the web and I'm sure you find a site with his info.

>c) I've been told that the sensors in drum pads are binary (ie off or on
>when a certain threshold is reached), is this true? My problem is that
>percussive dance isn't this discrete...a limited number of levels would be
>fine but just on/off would be very limiting.

The system described above is velocity sensitive: the harder you hit the
pad, the higher the MIDI Note On velocity will be. Thus, harder strikes can
be used to produce louder notes, or differing timbres.

>d) Finally I've heard of an impact-sensitive peripheral for the Sony
>Playstation previewed at a Japanese trade-show for the home version of the
>Japanese arcade hit bust-a-move (basically follow the on-screen disco moves
>with your feet). Any more info?

No idea abou that!

Hopefully this all helps. Good Luck.

Ciao,
Mark Coniglio

================================================================
Mark Coniglio, Artistic Co-Director | troika@panix.com
Troika Ranch Dance Theater | http://www.art.net/~troika
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