[sdiy] Measuring Input and Output Impedance

[Justin Owen]

-----Original Message-----
From: David G. Dixon [dixon at interchange.ubc.ca]
To: 'Mark Rivera'; 'Synth DIY'

>> I was looking at the following page and wondering...
>> http://www.learnabout-electronics.org/ac_theory/impedance73.php
>> Can I substitute a (modular's) module for the 'amplifier' in these
>> examples and know what my module's i/o impedances are?


> Alternatively, you could just look at the input resistors.  The impedance of
any input through a resistor into an inverting opamp (which describes most
module inputs) is simply the value of the input resistor.  If there is a
attenuator pot in the line, then this creates a divider into a parallel
resistance, depending on the pot setting, and a bit of algebra is involved.


Based on the '1K resistor' conversation we've had recently - what impedance do you use for inputs and outputs?