i am planning for an arduino with 16 piezos as drum surfaces.
i hope to use the 4051 multiplexer in order to get the extra ins.
the 4051 multiplexer has an input impedance of 1.2k ohms.
arduino’s dital pins have an impedance “equivalent to a series resistor of 100 Megaohms” in front of the pin.
i couldnt find specs on arduino’s input impedance on its analog pins.
in the comments of this thread: http://todbot.com/blog/2006/10/29/spooky-arduino-projects-4-and-musical-arduino/, todbot says that the multiplexer…
must have really high input impedance (around 10 Mohms) so you can sense the piezo’s output voltage.
is it possible to raise the input impedance of the 4051, with, as the arduino literature describes, “a series resistor of 100 Megaohms in front of the pin?”
any guidance on the issue would be much appreciated.