1n4001 vs. 1N4007

[mysticaxe]

I've looked at a few projects that call for 1n4007 diodes in the power section.  I have a bunch of 1n4001 diodes hanging around.  The only difference I can spot is the voltage allowance of 1000V vs. 50V.  Is there any way a stompbox powered at 9V will see a swing of more than 50V?  Are there any places where a 1n4007 would be needed over a 1n4001?

[midwayfair]

Anything in the 1N400X series is interchangeable for stompbox purposes.

Plenty of the parts of a circuit, especially an op amp design, never see more than five volts, never mind fifty.

[mysticaxe]

That is what I thought - how can a 9V supply generate more than 50V?  I just wanted to verify as I'm putting together a Tayda order and want to cover about 6 possible projects.