walters said:
Does a BBD chip create degrees or phase angles?
because 40us=360 degrees
so if the BBD time period delay it 40us would that be 360 degrees?
Sounds like you're confused, first off, "degrees or phase angles" refer to the same thing, degrees is just a measure of phase angle.
Since you don't give much context, I feel I need to make sure you realize that 40us = 360 degrees ONLY for a signal of 25KHz, since 40us is the period of a 25KHz signal. In the case that you were dealing with a 25KHz signal, yes, a time period delay of 40us would be a 360 degree phase shift... if you fed any other signal frequency into it, the phase shift would be different.
if the difference between a phase shift and a time delay isn't intuitive, perhaps you should play around with some graphing software, and graph some sine waves of varying frequencies with different phase shifts and/or time delays. without an intuitive grasp on that, I think it will be hard to really understand how this system idea of yours will actually be working.
I can't speak with any real experience on the kinds of guitar effects systems it seems are the subject here. so I will provide my view from the standpoint of my knowledge of the theoretical/math side of it, which is about all they give you in college :lol:
for instance, do you understand why the time delay system will produce notches? it is because for certain frequencies, the particular time delay in use corresponds to a 180 degree phase shift. in a feedback system, if you feed back a 180 degree phase-shifted version of the input, the two signals cancel each other out, it's destructive interference.