Sample Loop editor

You're new to the LinuxSampler world? You don't know where to start and nothing works? Here's the place to ask for help.

Sample Loop editor

Postby wdubois » Tue Mar 25, 2008 6:35 pm

Forgive what may be an incredibly stupid question, but...

Can anyone point me to a linux-based sample editor that will allow me to tune and tweak the loop parameters? And, once established, write those into the wav file so gigedit/Linuxsampler can read them (probably in a 'smpl' chunk)?

I've been fruitlessly searching for such an editor for several days know and I've come to the conclusion that one doesn't exist in the Linux world. Barring this... can any of you sample-guru's explain just how you go about tuning the loops? (Yes, I know about the sliders in gigedit.)

- w
wdubois
Newbie
 
Posts: 7
Joined: Mon Feb 18, 2008 5:38 pm

Re: Sample Loop editor

Postby dahnielson » Tue Mar 25, 2008 8:09 pm

Hmm... I would like to know that too. I'm a little bit frustrated in some way with all the various editors available on GNU/Linux. IIRC, doesn't Rezound support loop points? Bear in mind that I haven't looped anything extensively since my hardware sampler days (why I omitted it in my "How to sample" post). But the basic process is as follows.

Finding loops
The important thing is to listen, the use of headphones is advised at this stage. What loop points will sound most natural without any further processing? A good loop editor should be able to suggest a number of loop points for you to judge and nudge. What to look, eh, listen for:

* As long as possible.
* With the smallest possible amplitude difference between the start and the end.
* The start and end should be at zero crossings (easily found by hitting Z in Audacity for example).

Processing
If the sample can't be looped without processing; only then process the loop portion.

* Compression to even out any variations in amplitude.
* High-pass filtering to remove annoying repetitions in the lower frequencies that only will be audible when looped. Think about it like the high-pass filtering of a texture to seamless and repeatedly texture a wall in a computer game.

Release tails
One problem with long loops is that there might be a long delay between releasing the note and getting to the release tail (the part after the loop's end point) of the sample if you choose to keep it and instruct the sampler to use it. Some samplers let you jump directly to the tail when a note is released or, as in case of LinuxSampler, let you provide a separate release sample. If you decide to use the release tail portion as release sample then you must make sure it will sound natural when being played back upon note release. That is, matching the release samples start with the loop itself in terms of amplitude and frequency content.

Modulation
Modulation have a bad reputation because of all badly programmed sound modules and SoundFonts being released. But during looping modulation is your best friend that let you cover up rough edges. As long as you understand the whats and hows of the sampled instruments, it can bring back some of the qualities removed by all looping and processing. Don't fear the modulator!
Anders Dahnielson

Ardour2, Qtractor, Linuxsampler, M-AUDIO Delta 1010, Axiom 61, Korg D12, AKAI S2000, E-MU Proteus 2k, Roland R-5, Roland HP 1300e, Zoom RFX-1000, 4GB RAM x86_64 Intel Pentium Dual 1.80GHz Gentoo Linux
User avatar
dahnielson
Moderator
 
Posts: 632
Joined: Wed Jan 23, 2008 11:25 pm
Location: Linköping / Tranås, Sweden

Re: Sample Loop editor

Postby wdubois » Wed Mar 26, 2008 1:13 am

Anders, Thanks for the reply.

I thought I'd run across a looping capability in Rezound (it does let you play a loop in the editor), but I have yet to find a way to mark it and save it. As far as I can see, it will let you loop on your selection (or the entire sound if you wish) so I wouldn't think it would be that far of a leap. Perhaps if I get brave enough to delve into the source, I'll add it myself. Dunno if my programming chops are quite up that, though.

Thanks BTW, for the tips on looping. Your posts are almost always fascinating and informative. One of these days, we should collect them and package 'em up in a 'Sampling How-To'. Thanks for taking the time to write some of this stuff down. It really helps (me, anyway) to read the techniques of someone far more experienced. While I've been involved with analog (& digital) synthesis for quite awhile, somehow I managed to miss the entire sampling thing. Now, with such an excellent tool as LS to play with, I can't stop! :lol:

- w
wdubois
Newbie
 
Posts: 7
Joined: Mon Feb 18, 2008 5:38 pm

Re: Sample Loop editor

Postby dahnielson » Wed Mar 26, 2008 1:31 am

I'm glad to help. :-)
Anders Dahnielson

Ardour2, Qtractor, Linuxsampler, M-AUDIO Delta 1010, Axiom 61, Korg D12, AKAI S2000, E-MU Proteus 2k, Roland R-5, Roland HP 1300e, Zoom RFX-1000, 4GB RAM x86_64 Intel Pentium Dual 1.80GHz Gentoo Linux
User avatar
dahnielson
Moderator
 
Posts: 632
Joined: Wed Jan 23, 2008 11:25 pm
Location: Linköping / Tranås, Sweden

Re: Sample Loop editor

Postby dahnielson » Wed Mar 26, 2008 7:10 am

wdubois wrote:Thanks BTW, for the tips on looping. Your posts are almost always fascinating and informative. One of these days, we should collect them and package 'em up in a 'Sampling How-To'. Thanks for taking the time to write some of this stuff down. It really helps (me, anyway) to read the techniques of someone far more experienced. While I've been involved with analog (& digital) synthesis for quite awhile, somehow I managed to miss the entire sampling thing. Now, with such an excellent tool as LS to play with, I can't stop!


BTW, a proper manual for Gigedit is on my ToDo-list.
Anders Dahnielson

Ardour2, Qtractor, Linuxsampler, M-AUDIO Delta 1010, Axiom 61, Korg D12, AKAI S2000, E-MU Proteus 2k, Roland R-5, Roland HP 1300e, Zoom RFX-1000, 4GB RAM x86_64 Intel Pentium Dual 1.80GHz Gentoo Linux
User avatar
dahnielson
Moderator
 
Posts: 632
Joined: Wed Jan 23, 2008 11:25 pm
Location: Linköping / Tranås, Sweden

Re: Sample Loop editor

Postby wdubois » Wed Mar 26, 2008 4:55 pm

Fantastic! I look forward to it.

Meanwhile... back to the source... :shock:
wdubois
Newbie
 
Posts: 7
Joined: Mon Feb 18, 2008 5:38 pm


Return to Newbies & Support

Who is online

Users browsing this forum: No registered users and 7 guests

cron