OLPC XO + LinuxSampler = poor man's instrument ?

[sbenno]

http://www.linuxjournal.com/content/mus ... t-releases

Dave Philips writes:

Is till owe you all some news about the LinuxSampler project, and did I mention that I'm now the proud owner of an XO laptop ? More about all that when we meet again.

Dave, this is interesting, a guy working with children which will get XO laptops asked about turning them into cheap a musical instruments.

It would be cool if you could try to run some tests by running LS on the OLPC (one laptop per child) XO machines trying to optimize parameters like number of voices, ram preload sizes, stream buffer sizes etc.
we can assist you in case questions do arise, just ask here.
From reading the specs it could become a quite capable cheap instrument. The XO uses a flash disk so one can probably reduce the RAM preload sizes as the disk should in theory
seek much faster than normal HDs.

Perhaps OLPC XO (or similar) hardware + LS along with free sample libs could contribute to providing access to high quality digital instruments for poorer populations, it would be a nice achievement.

MIDI master keyboards are getting cheaper too,
this one from m-audio for example, currently costs $129
http://www.m-audio.com/products/en_us/K ... -main.html
According to the informations I've read you can connect those MIDI keyboards to the PC via USB (no extra MIDI interface required therefore no additional expenses) and the hardware is supported by ALSA.


Dave, let us please know about the performance tests (without hurry)

BTW can you compile apps directly on the XO or due to the low specs does one have to compile it on a regular PC using sort of sandbox, cross compile environment etc ?

thanks,
Benno

[davephillips]

Hi Benno,

Sorry, I have to make this reply rather short.

I'll try doing LS with the XO as soon as I get past this week. I have a deadline tomorrow for the XO article, and I have to prepare for two different kinds of performances this weekend. I'm swamped right now.

But yes, LS on the XO should be do-able. I'm just now getting into working from the command prompt, but it's a Fedora Linux box, should be pretty easy to set up for development. I'll keep in touch with you about this topic.

Oh wait, I just remembered: No JACK on the XO yet, so that'll be my first step.

dp

[sbenno]

Hi Dave, thanks for the infos. As said no hurry at all, take all the time you need.
As for missing jack it would be interesting to hear if you succeed to compile and run it and what latencies you
are getting from it. Otherwise you could try with the LS ALSA driver. It is currently limited to 16bit audio but I don't think
the XO comes with a 24bit audio card, according to Wikipedia the audio chip is AC97 compatible.
But if you get jack working it would be better as it allows to add FXes to the LS output.
It would be interesting to know if the XO is able to load the Maestro Concert Grand v2 and what polyphony is achievable
both in dry mode and in conjunction with a not so CPU heavy reberb. (BTW what's currently the reverb with the best quality per cpu load ratio available on linux?)

Dave, if you succeed getting satisfactory numbers out of the XO it would be cool if you could write an acticle about it (steps to setup how to compile, tune the system,
perhaps provide a precompiled binary, recommended acessories like cheap MIDI master keyboards etc).
I think since the XO will have a very large user base this article will be interesting for many.

Thanks again for all your contributions to the linux audio world,
cheers,
Benno

[davephillips]

...you could try with the LS ALSA driver. It is currently limited to 16bit audio but I don't think
the XO comes with a 24bit audio card, according to Wikipedia the audio chip is AC97 compatible.

Oh yeh, I forgot that LS also does ALSA audio. That's good news.

Yes, the chipset uses the AD1888 AC97 implementation, which only goes up to 20-bit resolution.

But if you get jack working it would be better as it allows to add FXes to the LS output.
It would be interesting to know if the XO is able to load the Maestro Concert Grand v2 and what polyphony is achievable
both in dry mode and in conjunction with a not so CPU heavy reberb. (BTW what's currently the reverb with the best quality per cpu load ratio available on linux?)

The XO's installed memory is 256 MB, not a lot.

WRT reverb: jconv is pretty good, but I haven't compared CPU consumption of the reverbs available for Linux (there are some good ones). I use the CAPS Plate Reverb LADSPA plugin a lot, it's simple to control and I like its sound.

Dave, if you succeed getting satisfactory numbers out of the XO it would be cool if you could write an acticle about it (steps to setup how to compile, tune the system, perhaps provide a precompiled binary, recommended acessories like cheap MIDI master keyboards etc).
I think since the XO will have a very large user base this article will be interesting for many.

Well, let's see how far I can get. I'll have time to start working on it next week. First I need to upgrade the system software, then I need to set up a development environment. There's plenty of information on the Web that can help, I don't think I'll have much trouble getting started.

Thanks again for all your contributions to the linux audio world.

You're quite welcome. Thanks for yours !

[SteveB]

Hi

I found this thread and read it with great interest: I just picked up an started using an OLPC X0 laptop that had been sitting on the shelf here for most of last year. I am very interest in trying to use it to sample sounds in very difficult-to-get-to places and use it with LS and a USB keyboard to make music with those sounds (also in fairly remote places).

Did the experiment discussed in this thread go anywhere? I would love to experiment with putting it to use but I am just a fairly average Jo (not a Linux, or LS expert). I just want to use it as part of a music project in remote communities (if it can be made to work).

I really appreciate the work that people like you put into projects like this. I hope that someone with real brains has got it to work

[davephillips]

Did the experiment discussed in this thread go anywhere?

Alas, no. I still have my XO, but my time is severely limited and I'm unlikely to try the experiment any time soon. The memory and CPU for the machine are very small, I'm not very hopeful that LS will run in it. Of course, someone should still try.

Best,

dp