Good Re-sampling tool for single cicle waveforms?

[Juan Mendoza]

Hi all!

I'm recording some analog waveforms from my HW synths and i need to take single cicle waveforms (i.e. one cicle of a saw or a sine wave). Then i need to re-sample each wave so that it matches exactly 4096 samples.

Do you know of an app or tool to do this acurately?
32 or 24 bit support?

Thanks in advance!

Juan


PS: I've searched in the forums and i've found some topics about this but none with an app that supports 24 or 32 bit

[Juan Mendoza]

bump!

[chroma]

does it really have to be exactly 4096 samples? that's like 10-40 Hz.

if you just want some basic waveforms.... there are easier ways to do this. i used to have a C program to do stuff like this, dunno if I still have it but that was years ago and I've seen at least 3-4 other tools since then that do the same thing, + things like Alchemy which support that sort of thing natively, or ableton live's additive support. pure waves are pretty easy to reproduce additively at any frequency.

If you're trying to sample a HW instrument to reproduce it, especially an analog... you could sample at 192K and lower to ~40Hz and sample it, and you'd get a single cycle about 4096 samples (you could probably tune it, though it would be hard to get it exactly!) For analog especially though, the oscillator shape at a higher octave will be subtly different than one at lower octaves. If you sample at, say, A4 (=440Hz) and stretch it to 4096 it's going to sound terrible (we're talking pitch shifting 3-4 octaves!)

Especially for analog as well, you want to get some of the drift in the oscillators, so you really want to sample a whole bunch of cycles, not just one.

hope this helps some... really, it depends on what you are trying to do though.

[Kriminal]

Mathematica

[Juan Mendoza]

does it really have to be exactly 4096 samples? that's like 10-40 Hz.

if you just want some basic waveforms.... there are easier ways to do this. i used to have a C program to do stuff like this, dunno if I still have it but that was years ago and I've seen at least 3-4 other tools since then that do the same thing, + things like Alchemy which support that sort of thing natively, or ableton live's additive support. pure waves are pretty easy to reproduce additively at any frequency.

If you're trying to sample a HW instrument to reproduce it, especially an analog... you could sample at 192K and lower to ~40Hz and sample it, and you'd get a single cycle about 4096 samples (you could probably tune it, though it would be hard to get it exactly!) For analog especially though, the oscillator shape at a higher octave will be subtly different than one at lower octaves. If you sample at, say, A4 (=440Hz) and stretch it to 4096 it's going to sound terrible (we're talking pitch shifting 3-4 octaves!)

Especially for analog as well, you want to get some of the drift in the oscillators, so you really want to sample a whole bunch of cycles, not just one.

hope this helps some... really, it depends on what you are trying to do though.

Hi and thanks for your reply!

I know how to create single cicle waveforms (inside Mulab i can create any kind of waveform of exactly 4096 samples and save it as .wav), but what i need to do now is sample some hardware intruments, and take a single cicle waveform to use it with Mulab's oscillator. It needs to be exactly 4096 samples long, and the problem is that some of the hardware i want to sample doesn't go even close to this value. I.e. I want to sample acidlab bassline but it's a 2 octave synth only . Same happens with a sidstation, it has more octaves but the lowest note is around c0, too far from a single cicle of 4096 samples.

Same applies to other HW i want to sample, so what i need is a tool or something that can resample this kind of waves acurately.

[Juan Mendoza]

... also i'd want to take existing single cicle waves already recorded and avalaible on the net and convert them so that they match 4098 samples as well.

[chroma]

ok, i actually installed mulab (free version) so I could see what you are talking about. short version - don't use the wavetable oscillator, use the multi-sample oscillator. I didn't look at it enough to really know what its capabilities are in this area - you will probably need to use something like audacity or maybe the free version of acid? to record, trim, and loop the wave files. But I did manage to throw a bunch of files into the multisamples (the 'aeon strings' posted around a few places a while back) and it automapped by name and looked OK. That would be the way to go, and with its modular interface (which is pretty cool... reminded me of jeskola buzz with a more modern sequencing interface) you still keep all of the programmability of the synth.

[Juan Mendoza]

ok, i actually installed mulab (free version) so I could see what you are talking about. short version - don't use the wavetable oscillator, use the multi-sample oscillator. I didn't look at it enough to really know what its capabilities are in this area - you will probably need to use something like audacity or maybe the free version of acid? to record, trim, and loop the wave files.

This all can be done inside Mulab (with a just a bit more development will be the best sequencer for composing ever, IMO). But really, what i want to do is import these waves inside those awesome oscillators. There are some good reasons to do this. Those osc work 100% alias free. You have a lot of control over the sound plus you can stack voices to make the sound fatter easyly. But one of the most important features, is the AIPS parameter

From mulab docs:

AIPS means AddInvertedPhaseShift. Simply put: with a Saw, this causes Block PWM. But it can be used with any waveform! And it can be modulated, e.g. by an LFO.

... with this parameter you can achieve very interesting effects and you can, as an example, emulate some charachteristics of the sound of a sid chip.

I know i can make multisamples and i also plan to make some for mulab, but this is a totally different project and what i need is just resample some waves, it couldn't be so much difficult but seems to be


B

ut I did manage to throw a bunch of files into the multisamples (the 'aeon strings' posted around a few places a while back) and it automapped by name and looked OK. That would be the way to go, and with its modular interface (which is pretty cool... reminded me of jeskola buzz with a more modern sequencing interface) you still keep all of the programmability of the synth.

... just give it a try! this app has changed my music in an awesome way

Again, thanks for your help

[chroma]

well, if that's really what you want... i remember cool edit could do this. you used the timestretch function. I don't remember if you could actually give it a number of samples, but you can probably give it a time corresponding to exactly 4096 samples (it did support time IIRC).

but you can simulate that (I know the saw technique you are referring to, it really is just add inverted + phase shift) by inverting the sample and mixing too, even with multisamples... you can't actually control the start phase this way, but if you're modulating it and it's moving it will sound about the same. Most samplers can't do inversion I don't think, but yours should be able to handle that.

there's no good reason the multisample oscillators shouldn't also be aliasing-free... after all, both the wavetable oscillator and the multisample oscillators are being pitch-shifted the same way, it looks like. Unless it is really an additive phase-accumulator oscillator (like Alchemy), which would make it interesting.

i'm too tied up in live to switch now

[teempee]

Sample your single cycle, measure it, take your calculator, pitch the percentage. If it's off by few samples then trim it.

[nix808]

I can give you a tool, but I think it will only be 16 bit? You can do it in SM with float array resample. you just punch in your final sample length. I think it has more than one kind of interpolation perhaps.

[Juan Mendoza]

Sample your single cycle, measure it, take your calculator, pitch the percentage. If it's off by few samples then trim it.

Thanks!

Do you know the formula i should use for this calculation?

[Juan Mendoza]

I can give you a tool, but I think it will only be 16 bit? You can do it in SM with float array resample. you just punch in your final sample length. I think it has more than one kind of interpolation perhaps.

That would be awesome

Even on 16 bits should be fine

Please give me a link or something.

EDIT: sorry, with SM you mean Synth Maker right?

[Juan Mendoza]

I've downloaded and installed synthmaker's trial but i dont find the resample component or the Float Array Resample. I'm a noob with this app, if you know where it is please let me know,

Thanks

[nix808]

Sorry man for the late reply. I'll wire the .osm now.