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massively stuck with circular buffer reverse real time sound thingy


Feb 03 2010 | 8:51 pm

i can’t quite get this right in my head, i am sure there is a way to do this with just buffer~ count~ poke~ index~ but i cannae quite get there captain

had a look at some of the tapin/tapout things but can’t figure them out, i’d like to understand them, not just copy paste.

any help greatly appreciated

Feb 03 2010 | 9:38 pm

Did "having a look at some of the things" include a little quality time with MSP tutorials 26 and 27 on delay lines? I think they’re quite clear at explaining what’s going on, and might at least provide a decent baseline for your next questions….

Feb 03 2010 | 9:45 pm

You can do the reversing with a [!-~ ] right before index~. Just send the length of the circular buffer into its right inlet and it will output the reverse sample index. I’ve made a couple of circular buffer patches with count~ poke~ and index~, and I’ve found them very interesting with modulated feedback loops (I’m still not entirely sure I couldn’t do it all more simply just with tapin/out~, but ne’er mind…….it’s interesting to experiment). You will run into clicking problems if the "record head" crosses the "play head" so to speak, which is likely with reverse stuff.

Feb 03 2010 | 10:05 pm

…but those clicks are features, not bugs.

Feb 03 2010 | 10:16 pm

: ) a bit of nicely timed glitch can sound great

Feb 03 2010 | 11:50 pm

here’s what i’m messing about with


-- Pasted Max Patch, click to expand. --

Feb 12 2010 | 10:56 am

Hi Raja thanks for taking the time to look at it

I’ve highlighted the problem with the clicks, most of the time this isn’t that evident but with a sine tone its easy to hear


-- Pasted Max Patch, click to expand. --

Feb 12 2010 | 11:32 am

Hi Mike,

I can’t get your patch to click/pop either. I created a simplified version here and I still can’t get it to glitch:

— Pasted Max Patch, click to expand. —
Feb 12 2010 | 2:51 pm

Hi Sixtin, this is my code from above with the sine wave but this time with a loadbang! I definitely hear clicking in the reversed (right) channel, which must be from the write head crossing the read head or something like that. i have on one occasion had no clicking but i presume that was a fluke as i’ve tried many combinations of vector sizes. obviously doing this with the count~ method is going to require a bit more than this simple approach


-- Pasted Max Patch, click to expand. --

Mar 08 2010 | 6:47 am

Cool patch!

At least some of your clicking (that at the "loop points") is simply caused by waveform discontinuities, which are exaggerated by the choice of such a pure source, I tried a few samples in your original patch and did not here any clicking.

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Forums > MaxMSP