[LAU] Sustain pedal issue with undesired repeated notes (m-audio keystation 88es + qjackctl + qsynth)

[david]

Nicolas BERCHER wrote:
> On 06.06.2010 23:44, Ken Restivo wrote:
>> On Sun, Jun 06, 2010 at 10:15:03AM -0400, Dave Phillips wrote:
>>   
>>> Nicolas BERCHER wrote:
>>>     
>>>> I have a problem I can't face alone on the digital piano I made on
>>>> Debian Lenny with qsynth (v0.2.5-2.2), qjackctl (v0.3.2-1) and an
>>>> m-audio keystation 88es keyboard.
>>>>
>>>> When I play the piano, some notes will repeat themselves after a few
>>>> seconds only if I keep the sustain pedal pressed, just like a delay
>>>> effect would do.
>>>> I reported that only 4 notes are concerned for the moment, they have
>>>> different repeat delays:
>>>>   G  : ~7.5 sec (G4)
>>>>   G# : ~7 sec (G#4)
>>>>   A  : ~6.5 sec (A4)
>>>>   A# : ~6 sec   (A#4)
>>>> Note that the notes above, relatively to the middle C of a piano
>>>> keyboard called C3, goes from G4 to A#4.
>>>>
>>>> Could this be due to an hardware issue in the m-audio keyboard?
>>>>
>>>> Thanks a lot for any idea on how to track down and correct this (if
>>>> possible).
>>>>        
>>>
>>> Try putting a MIDI monitor program between the keyboard's MIDI output
>>> and QSynth's input port in QJackCtl. Look for the repeats there.
>>>
>>> If you have KDE: http://kmidimon.sourceforge.net/
>>>
>>> For Gnome/GTK: http://home.gna.org/gmidimonitor/
>>>
>>>      
>> For none of the above (my preference): aseqdump :-)
>>
>> -ken
>>
>>    
> Thank you for answers.
> Yes, I also prefer command line tools! ;-)
> So, I checked what's going on:
> $ aseqdump --list
>  Port    Client name                      Port name
>   0:0    System                           Timer
>   0:1    System                           Announce
>  14:0    Midi Through                     Midi Through Port-0
>  20:0    SB Live! Value [CT4870]          EMU10K1 MPU-401 (UART)
>  24:0    USB Keystation 88es              USB Keystation 88es MIDI 1
> $ aseqdump -p 24:0
> Waiting for data. Press Ctrl+C to end.
> Source_ Event_________________ Ch _Data__
>  24:0   Control change          0  64 127
>  24:0   Note on                 0  82  82
>  24:0   Note on                 0  82   0
>  24:0   Control change          0  64   0
> 
> The above sequence dumped by aseqdump shows only one note event (lines 
> 2+3: press+release) but I heard a delayed note as mentioned in my first 
> mail.
> The keyboard seems to do things right, so I think it comes from qsynth.
> Isn't that strange? I mean many people around there use qsynth, am I the 
> only one to have this kind of problem?

Hmm, have never had QSynth repeat a note unless I actually repeated a 
note. Interesting. I don't know the innards of MIDI events, so don't 
know what the various numbers above mean.

WAGging around: Is your USB MIDI connection sharing a USB bus with other 
USB devices? Maybe some other USB device is doing something weird with 
the bus and something isn't getting handled right?

-- 
David
gnome at hawaii.rr.com
authenticity, honesty, community