|What's the point?
What we're doing here is combining
a standby switch (aka a silent switch) and a
switch, only with a twist. See, a conventional kill switch only
cuts the signal when pressed. However, some readers of this site
have requested an option by which the switch could be used in the opposite
fashion. In other words, what if the guitar was silent except when
the button was pressed? Musically this presents some new options,
but it also makes the guitar difficult to operate if you aren't actively
pressing the momentary push-button to allow the signal to pass through
it, and who wants to play like that most of the time?
What we're going to do here is have a SPST
in the circuit that by default throws the signal to a "normally open" push-button
switch. At this point, we have effectively created a standby switch
for the guitar. When the signal is sent to the push-button, the signal
will be cut... but only until the push button is pressed. You now
have both options available to you.
You'll need a SPDT* to function
as a standby switch. In this case we aren't cutting the signal so
much as re-routing it to the push-button.
*A DPDT will work as well if you have one
of those or a push-pull pot lying around.
As mentioned above, you will need a "normally-open"
push-button switch. A normally-closed switch would allow the signal
through unless it is pressed. If you installed that, the "standby"
switch wouldn't accomplish anything without the button also being pressed,
so it would be redundant.