9V Spike When Using Stereo Jack For On/Off Switch

[KazooMan]

Using a stereo jack as the power switch works great but I have often wondered if there might be a problem.  As you insert the mono plug there is a point where the tip makes contact sending 9 volts back up the cable.  Are there any input devices that might not tolerate this?

[GibsonGM]

Honestly, I wouldn't think it's a problem. It's been going on for years, after all....
besides the folk-knowledge of no reported problems, we have to consider the input impedance of most devices, which are relatively high - so they don't draw much current and therefore I see no real 'burn out' danger there.   My .02.   

[KazooMan]

Yeh, I've never heard of anyone having their humbuckers go up in smoke when they plugged into a pedal.