[LAU] oh yoshimi, one more time

[David Adler]

I posted this to the wrong list first, thus now forwarding to LAU.

---------- Forwarded message ----------
From: David Adler
Date: Sat, Jan 30, 2010 at 9:18 AM
Subject: Re: [LAU] oh yoshimi, one more time
To: yoshimi-user at lists.sourceforge.net


david wrote:
> Folderol wrote:
>> david wrote:
>>> Folderol wrote:
>>>> Emanuel Rumpf wrote:
>>>>> I don't know if this is known:
>>>>> Yoshimi 054 pre2 and pre4 both disconnect from jack, when pressing
>>>>> many keys (~10) at the same time on my midi keyboard.
>>>>> This does not happen with yoshimi 038
>>>>>
>>>> Cant repeat that here. Are you using jack-midi or alsa-midi? I'm using
>>>> alsa-midi.
>>>> I can stick both arms down flat across the keyboard without it
>>>> disconnecting - get rather a lot of xruns though!
>>> Hmmm, I've noticed that if I have a lot of notes going (play fast scales
>>> with sustain pedal down), adding new notes will cut off existing ones.
>>
>> That's normal behaviour and dependent on the number of notes of
>> polyphony set at compile time ( haven't a clue what the default is) and
>> the release time of the notes.
>
> Yoshimi is set for 256, I think that's the default.
>
>>> Last night I was playing something into Rosegarden, and noticed that
>>> sometimes a run of notes simply wouldn't happen - appear in Rosegarden
>>> or play through Yoshimi.
>>
>> If they don't even appear in Rosegarden then I wonder if you've got
>> MIDI set up correctly. Is it a USB keyboard? I believe they are
>> inclined to have latency problems and you might just be overfilling the
>> 'pipe' :o
>
> It's a MIDI keyboard (Yamaha PSR225GM) without USB capability. The
> XMidiPort provides 2 standard MIDI cables at one end and a standard USB
> connector at the other. It is connected into a USB hub that has a number
> of other things connected to it (none in active use).
>
>>> I didn't get any xruns, and didn't see any messages from JACK about any
>>> problems.
>>>
>>> Using JACKDMP using alsa-midi (E-Mu XMidiPort 1x1 over USB 2 port and an
>>> external USB sound card hooked to a different USB port). Yoshimi 0.053.2.
>>
>> Looks even more like a straight MIDI problem.
>
> I'll have to try it without Yoshi running.
>

I just did some 'play many notes'-testing with
yoshimi 0.053.3 and 0.053-pre4 and Ohh Choir.xiz.

Without sustain:
The first note is dropped as soon as I press the
16th one.
yoshimi continuously reacts on new notes.

With sustain (or long release time):
The 8th to 16th note. (depending on ? and
the patch used)

When playing fast, yoshimi reports 'to many notes'
and refuses to react on new notes until calmed
down.

This might not be yoshimis fault, as it happens
even with the default sine wave at << 10 % cpu
usage.
OTOH, when playing Aeolus in the same way (via
USB -> seq driver -> Jack MIDI) this limit does not
exist.


No xruns appeared during the above tests, so I
tried teasing a little more.

'Ohh Choir.xiz', without sustain:

-p 3 -n 64 (not used for real work)
Pressing many notes, hundreds of xruns appear
at ~ 50% cpu usage (as reported by qjackctl).

-p 3 -n 128
No xruns at all. When repeatedly pressing as many,
many notes as possible with my arms, the 'to many
notes' messages appear again, yoshimi interrupts
response on new notes for a while (as above).

I added some SUBsynth and ADDsynth to the
choir pad and was able to zombify yoshimi 0.053.3
at about 80% cpu usage. Still no xrun.

All this with an E-MU 0202 USB and a non-rt kernel,
quite pleasant.


best,
d