Subject: Re: [linux-audio-dev] Reverse-engineering files
From: Jay Ts (jay_AT_toltec.metran.cx)
Date: Thu Nov 30 2000 - 02:11:59 EET
Paul Winkler wrote:
> <exposition style="rant">
> I recently bought a Yamaha SU700 phrase sampler.
> While it has some really cool features [...]
> ... it has so many really stupid limitations
> that I'm determined that this will be the last piece of dedicated
> digital hardware or closed-source software I will buy.
I could say the same about my new E-mu Xtreme Lead-1 sample playback
synth, except that I would really like to have about 10 more E-mu
products. I like them, even with their limitations.
> One of the big dumb issues is that its support for working with a PC
> is unbelievably limited.
> All you can do is import and export AIFFs on a floppy disk,
The XL-1 doesn't even have that. The way to get sounds into it is
to spend about $2000 on an E-mu Ultra sampler, plus another $300 on
a flash SIMM! The designers could have included either an ethernet
or USB interface pretty easily, but they didn't.
My intention here is not to complain, but to point out that in the
future, I'm expecting synths and other music electronics to be increasingly
computer-enabled. Right now, there are a few products like the Clavia
Nord Modular (programmed on the computer and downloaded into the module
as its intended manner of use). And there is serious competition developing
by the likes of Gigasampler. In a few years, the dedicated hardware
makers will *have* to be selling equipment with good computer interfaces,
or they'll be history.
In the meantime, we're dealing with the intermediate, not-quite-there-yet
products, and that's just life on the leading edge, as far as I can figure it.
Anyway...
> So I'm sneaking in the back door. I've got about 90% of the sample
> file format figured out and I can now read and mostly write its
> proprietary file format [...]
Yee Ha! Paul, good for you! That's the spirit.
> Now my question:
> I don't suppose anyone else on this list has one of these samplers?
I doubt it, but we'll see. While we're at it, anyone else have an E-mu
Proteus family synth module? I've been thinking about writing something
like Emagic's SoundDiver (for preset programming and management) but it
doesn't make sense to put in all the work on my own.
> And I don't suppose anyone has the time or inclination to help me
> figure out the last bits of the file format?
I'm way too busy and don't have one of the units, but maybe I can
waste some of your time with suggestions... ;)
> There's about 10 bytes of the header that I have no idea what they do,
Interesting. If they are checksumming, you could be SOL if you can't
figure out how the sum is computed.
From what you wrote here, I'm not sure what kind of working functionality
you have. If you have the ability to use some kind of software to
create floppies that the unit can read, starting from your own sounds,
then try creating incredibly simple "sounds", like a single sample.
Then use different values of that sample, and see how the file changes.
Then go on to a 2-sample square wave, or something like that.
But of course you probably tried that already, right?
- Jay Ts
This archive was generated by hypermail 2b28 : Thu Nov 30 2000 - 04:11:49 EET