work with Linux ?
> Tim Goetze <tim(a)quitte.de> writes:
>
> there's a difference though: the usb 1 ms is jitter, there's no way
> to reconstruct the original timing. this in contrast to midi, where
> you can extrapolate the exact event time quite well (provided you're
> looking at a stream of mostly isolated events). oh well, most people
> think 1 ms is below human perception limits anyway.
People who are into this topic might want to take a few minutes
to review Appendix C.1 (pp 66-70) of the MWPP draft:
http://www.cs.berkeley.edu/~lazzaro/sa/pubs/txt/current-mwpp.txt
It basically describes the three methods MWPP provides for coding
timestamps onto MIDI commands when packetizing a MIDI stream. The
goal is that whatever your MIDI source is (a MIDI 1.0 DIN jack,
an algorithmic composition program, etc), one of these three
methods will be the right one to capture the timing as best as
can be, into an RTP packet. Feedback is welcome on the topic,
we're starting to close in "Last Call" for the document, but
there is still a few months left ...
-------------------------------------------------------------------------
John Lazzaro -- Research Specialist -- CS Division -- EECS -- UC Berkeley
lazzaro [at] cs [dot] berkeley [dot] edu www.cs.berkeley.edu/~lazzaro
-------------------------------------------------------------------------
Hi,
I meant of sending midi events from the master keyboard via USB to the PC
which runs an internal soft-synth/sampler.
In that case USB should improve timing because of the bigger bandwidth,
(but will add 1msec of latency due to USB1 polling mechanism as far as I can
understand).
Correct me if I'm wrong.
cheers,
Benno
You wrote:
-----
> Ok if the Edirol keyboards support standard MIDI then there shouldn't be any
> problems using them under Linux, but since USB has a much bigger bandwidth
> than serial MIDI, I that the timing for notes that belong to large chords is
> more precise. Can someone confirm this ?
Not really, unless you are spreading those chords on several separate midi
outputs. If it just one, then it determines the bandwidth available.
Getting things faster to the interface will do nothing because it still
has to send the bytes to the external synth at the same old slow 31250
baud speed.
-----
--
http://linuxsampler.sourceforge.net
Building a professional grade software sampler for Linux.
Please help us designing and developing it.
there has been a massive spam attack against linux-audio-dev yesterday.
expect longer round-trip times and even more anal filtering while i'm
tracking this down.
regards,
jörn
--
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get the new "blue" version of rtsynth from:
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enjoy,
Stefan
P.S. An updated jackified version will follow as soon as i can
test it on my machine in RT mode.
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> AFAIK the Oxygen8 does not behave as a standard usb midi device, it uses a
> "Midiman protocol" instead, so the standard drivers don't know what to do
> with it. If you connect it and do an lsusb -v you don't see much...
Ok if the Edirol keyboards support standard MIDI then there shouldn't be any
problems using them under Linux, but since USB has a much bigger bandwidth
than serial MIDI, I that the timing for notes that belong to large chords is
more precise. Can someone confirm this ?
BTW: the Midiman site lists Linux as an OS in their driver search page but
nothing comes up when searching for product drivers.
Is their stance very closed ? Do they not even release specs ?
cheers,
Benno
--
http://linuxsampler.sourceforge.net
Building a professional grade software sampler for Linux.
Please help us designing and developing it.
> good god. know an alternative source for calculating the
> coefficients? Bill?
The classic article, in this context, is
"Digital Waveshaping Synthesis"
Marc Le Brun JAES 1979 April, vol 27, no 4, p250
Daniel Arfib, at the same time but independently, did similar work --
I don't know a reference. I think DiPoli wrote a good overview --
perhaps in Roads "The Music Machine"?
CLM has code both for the table-oriented and polynomial-oriented
approaches. There's an example "brighten" instrument in clm.html.
>From: Fernando Pablo Lopez-Lezcano <nando(a)ccrma.Stanford.EDU>
>Is anyone out there trying out this combination?:
>
> kernel 2.4.20-rc1
> capabilities patch
> low latency patch
> preemptible kernel patch
> almost current alsa cvs [20021028.170432 usa pacific time]
>
>If I start jackd and then use the freqtweak jack client I get a completely
>dead machine in a very short time (from a few seconds to 10 or 20
>seconds).
>
>...
>
>Interestingly enough just the jack server running is not enough to kill
>the machine. Adding a jack client (just tried alsaplayer, same problem as
>freqtweak) kills the machine really fast.
>
I have excactly the same problem since i upgraded my machine to SuSE 8.0,
which is based on: kernel 2.4.19-SuSE + capabilities patch + low latency
patch.
Stefan
_________________________________________________________________
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i don't want to blow my moderator points this time, so get busy. there
is lots of confusion, mis-information and general cluelessness in the
responses so far. get to it, provide me with some stuff to moderate
upward ...
--p
Havent been receiving any news lately, please help.
-----Original Message-----
From: linux-audio-dev-admin(a)music.columbia.edu
[mailto:linux-audio-dev-admin@music.columbia.edu]On Behalf Of
linux-audio-dev-request(a)music.columbia.edu
Sent: Saturday, July 27, 2002 9:00 AM
To: linux-audio-dev(a)music.columbia.edu
Subject: linux-audio-dev digest, Vol 1 #127 - 2 msgs
Send linux-audio-dev mailing list submissions to
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When replying, please edit your Subject line so it is more specific
than "Re: Contents of linux-audio-dev digest..."
Today's Topics:
1. Re: runtime / compiletime processing proof of concept (Paul Winkler)
2. Re: runtime / compiletime processing proof of concept (Juan Linietsky)
--__--__--
Message: 1
Date: Fri, 26 Jul 2002 13:00:10 -0400
From: Paul Winkler <pw_lists(a)slinkp.com>
To: linux-audio-dev(a)music.columbia.edu
Subject: Re: [linux-audio-dev] runtime / compiletime processing proof of
concept
Reply-To: linux-audio-dev(a)music.columbia.edu
On Fri, Jul 26, 2002 at 01:21:46PM +0200, Maarten de Boer wrote:
> Hello,
>
> Juan Linietsky (reduz on #lad) talked on #lad about an idea of
> Benno to have processing graphs generate source code, compile
> it on the fly, thus taking advantage of all compiled optimizations,
> as an alternative to runtime processing. Especially for sample
> based processing instead of block based processing this can be
> very useful and a lot faster.
John Lazarro tells me that sfront does something similar.
He says it's described here:
http://www.cs.berkeley.edu/~lazzaro/sa/pubs/pdf/wemp01.pdf
--PW
--__--__--
Message: 2
Date: Fri, 26 Jul 2002 14:38:40 -0300
From: Juan Linietsky <coding(a)reduz.com.ar>
To: linux-audio-dev(a)music.columbia.edu
Subject: Re: [linux-audio-dev] runtime / compiletime processing proof of
concept
Organization: Codenix
Reply-To: linux-audio-dev(a)music.columbia.edu
On Fri, 26 Jul 2002 13:56:55 +0200
Maarten de Boer <mdeboer(a)iua.upf.es> wrote:
>
> What i forgot to mention:
>
> The most interesting thing is that the code used for runtime, and
> the generated code used for on the fly compilation is actually the
> same! Which ensures that the result of runtime execution and
> compiling generated code -> execution is the same, and everything
> has to be written only once.
>
> maarten
>
Hi! Thanks for taking the time of writing a proof of concept program.
So far from what i've been reading it seems ok (didnt have much time
to check the entire code in detail) althought the real
advantage of compiling such graphs is when they are very large and
stack/buffer and indirection operations start to really slow it down.
Still, even whith this, i get (please tell me if these are correct):
realtime code: (./main)
real 0m1.005s
user 0m0.970s
sys 0m0.030s
runtime code: (./gen)
real 0m0.435s
user 0m0.370s
sys 0m0.060s
three seems to be quite a difference!
Juan Linietsky
--__--__--
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linux-audio-dev Mailing List Digest
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End of linux-audio-dev Digest
> -----Original Message-----
> From: Josh Green [mailto:jgreen@users.sourceforge.net]
>
>
> On Thu, 2002-10-31 at 19:09, Benno Senoner wrote:
> > Perhaps old news but I saw these interesting USB MIDI
> master keyboards
> >
> > http://www.harmony-central.com/Newp/2002/PCR-30-PCR-50.html
> >
> > I'm considering getting one so my questions are:
> >
> > - What's the status of USB MIDI on Linux ? Are such kind of
> keyboards fully
> > supported ? (eg transmit all the params as midi events or
> use special USB
> > message)
> >
> > - what kind of Note-on MIDI latency do these keyboards have ?
> > (standard midi keyboards 1.1msec)
> >
> > thanks,
> > Benno
> >
>
> New news to me! I was thinking of getting an Oxygen 8 for use with my
> laptop but was bummed about it not having a MIDI input or pedal
> controls. Both of which I see are included with those 2
> keyboards. Looks
> like I'll be getting one of those if they work in Linux of course :)
the specs say they have midi in/out (in addition to usb) so they should
work with linux, right?
quote:
"MIDI Interface (in/out), USB Interface"
erik