Timo Rozendal

I just discovered a weird problem with overdrive~ in combination with a few things. The problem exists with the latest max 4 (mac and pc) and max 5 (I checked only pc) as well.

-if and only if the incoming signal contains clicks (or abrupt changes)

-if and only if the signal is routed through a [freqshift~ ] object (the shift itself is irrelevant, even shift 0 'works')

-if and only if that signal is routed to an overdrive whose drive is controlled by a signal (not when it is controlled by a float)

--> then the output becomes really dirty, even with drive = 1.

i noticed the problem because this output can blowup biquads (resulting in a 'nan' output)

you can check this situation for yourself with the patch belowing and trying out the various situations, you will find out that it will only result in a dirty output when you have clicked all three green message boxes

placing a [bitsafe~] or [el.killdc~] object before or after the [freqshift~] doesn't help

can somebody explain this to me? what is [freqshift~] doing to the signal (inaudibly) that causes an [overdrive~] to behave like this? does it mess up the phase for wideband (click) signals? And why is this only a problem when the [overdrive~ ] is controlled with a signal object?

-if and only if the incoming signal contains clicks (or abrupt changes)
-if and only if the signal is routed through a [freqshift~ ] object (the shift itself is irrelevant, even shift 0 'works')
-if and only if that signal is routed to an overdrive whose drive is  controlled by a signal (not when it is controlled by a float)

--> then the output becomes really dirty, even with drive = 1.
i noticed the problem because this output can blowup biquads (resulting in a 'nan' output)

a-really-weird-problem-with-overdrive

I can confirm with Max 4.6.3 on Mac OS X Intel, the output sound goes wild. Seems quite buggy to me.

Did you check in the latest version of Max 5 (currently 5.0.4)? Some msp stuff has changed there, recently.

good point about the latest version, I still had to update to 5.0.4

I just did and... the problem remains (at least on a pc running xp)

good point about the latest version, I still had to update to 5.0.4
I just did and... the problem remains (at least on a pc running xp)


This should be fixed for the next incremental update.

a really weird problem with [overdrive~]