Forum to discuss all matters relating to the MPC1000 and MPC2500 operating systems created by 'JJ' (all versions).
By pipper Wed Jan 06, 2010 2:40 pm
Ok trying to get my head round this i am using a reverse loop so it reaches the end of the sample then reverses . Im using a kinda chord sound and just need to extend ther end a bit . SO why should the sound click as it reverses cos surely theres no jump in the waveform . I have also set the endpoint using the zero crossing button and it still clicks .Could someone explain why?

Also in the loop window what is the button on the left that looks like a slanting line , next to the zero crossing buttons , thanks.
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By mp3 Wed Jan 06, 2010 2:55 pm
Looping is a fine art. Clicks are the norm. Patience and practice will overcome that. And if all else fails (because some sounds are all but impossible to loop), you'll have to use an audio editor on your computer to do a crossfade loop.

In the loop edit window, only one side of the stereo sample is shown, so it may be that zero crossings on one side of the sample don't correspond to zero crossings on the other side of the sample. Also, if you're using alt loop with zero crossing then there is a natural discontinuity as the waveform reverses direction (in other words if the waveform is rising at the loop point, it will reach zero crossing, and then immediately begin to fall as it reverses direction). In the case of alternate looping, the best loop point is often not a zero crossing point, but rather a peak or trough (high or low point) of the waveform.

Another option is, if its a stereo sample, making it mono (or making two mono samples out of each of the left/right channels) and then looping it (or them) should make it easier. If you need to maintain the stereo sample, then you can assign both of those mono samples to separate pads, pan one left and the other right, and trigger them together (either manually or using simult pad).

The slanting line is kinda hard to put into words, but basically you can select zero crossings that occur on a rising slope (/) or falling slope (\). Its much easier to just toggle it (and then continue searching zero crossing points) and see how the waveform changes.

Good luck
Last edited by mp3 on Wed Jan 06, 2010 3:09 pm, edited 1 time in total.
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By Lampdog Wed Jan 06, 2010 3:10 pm
mp3 wrote:it may be that zero crossings on one side of the sample don't correspond to zero crossings on the other side of the sample.

I was just about to say that but you got the floor, preach on.
By jimmie Thu Jan 07, 2010 5:32 am
Try FADE OUT by 10ms at the end of your sample.

This will work for stereo and mono samples if you just can't get rid of the click by normal nudging of the loop. Also do FADE IN by 10ms if you're looping the entire sample and can't get rid of a click by normal means.