Is there a howto regarding samples (cylces looping) taken from a keyboard?

DSP, Plug-in and Host development discussion.
49 posts since 10 May, 2017

Post Tue May 08, 2018 9:55 am

I've been recording samples from a rompler keyboard, and certain samples go into "cycle looping" after about 2 seconds. Do you have something like an overview what I can do to get them "go on looping" on my PC with some software?

What I know is only that it is .. a static clycle thing, that I could try just a loop fine editor like in Renoise, a crossfade to get rid of the "cut points", interpolation, and to some extent I know I could create and play a spectrum like for example the earlevel code shows how to do. But I still need also the first part, the attack sound of pianos etc, to blend into it.

So, audacity is still recording the samples (for my personal use), they are all no more than 3 seconds, and I will need a cheap and easy (in terms of using free software, also gpl'ed) way to make them, as said, sound longer than 3 seconds.

I have no clue where to start. I mean, there must have been many people recording their home keyboards, no? ;-)

If .. you .. had a hint for me what to do, where to look, this would be so great.

Thanks a lot!

Oh and to be more precise, it's actually a JUNO-DS and I just think that most samples loop only the cycle and not much more, because some patches sounded like that, and the programming with the 4 parts and lfo makes them sound fluid. So, that would be not my goal for now. My goal now would just be "finding loop points" where no official documentation of the sample memory is. I assume there is nothing like that.

Edit: :ud:
The pianos are like looping the shortest possible cycle, the strings and pads seem to loop over more than one second. Two different things. From what I recollect about Renoise, it's great for the longer loops, and the loop crossfade would work great (it's some raw mono sound). But I'd still have to actually find good loop points because of the things going on in that second. The samples with tiny cycles on the other hand are good there, but will be out of tune compared to the non-looping portion, because .. well.. there's only integer loop points in Renoise and I did not make the JUNO play the samples at the frequency (don't know its sample rate .. uh, don't have to) that would give me integer loop points that would stay in the right frequency, I've just made it play C-4,D#4 and so on at its tuning set to 440Hz.

Soo.. I could just make music with notes that are not longer than the samples I record. :dog:

Regarding the frequency to ask the JUNO for... I can let it play at a divisor of the frequency at which I record it, by changing the master tuning or knowing what the pitch bend does. But then I cannot get many key zones, I believe. Well, I could trigger more keys, thus keyzones, and then pitch bend it immediately to a divisor. Or forget about it.

So, for Renoise or any sampler (?) I guess I could do this (?), if I have recorded just arbitrary keys from a rompler: pitch it down to the next frequency where an integer loop length will have the correct frequency. Then use the fine tune setting of the sample to get it back, so, the pitch down = resample.

But if I had my own sampler, I would not change the sample, I would just want a floating point loop length. And streaming samples from disk. That's why I haven't done anything yet.

145 posts since 12 May, 2012

Re: Is there a howto regarding samples (cylces looping) taken from a keyboard?

Post Wed May 09, 2018 5:37 pm

i learned some good stuff playing with fairlight samples. because they sampled with variable sampling rate the loops were always in blocks of 128, which usually always corresponded with period length. they seemed to take effort to maintain phase coherence too

before i figured that out i was having some success keeping the loop length ins samples close to the frequency and fine tuning indivudually per sample. if you think about it, keeping it close to period length you're less likely to run into clicks because most of the time the waveform is at a similar spot in phase. if there is a click, often you can just move the loop forward or backward a bit and it goes away. or add or subtract a few samples to the loop length which could knock it out of tune or even help it if the sample wasnt perfectly in tune

i would prefer to to knob adjust loop length centered on sample pitch live in reaktor than to try to find them flying blind in some audio editor any day of the week

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