On Wed, July 18, 2012 10:14 pm, Ralf Mardorf wrote: > Using USB for MIDI is tough ;).
Testing it seems to be harder. There are things I can do where I can hear a problem, but anything I have tried so far to create a measurable problem has failed. While it is obvious to my ear that giving audio group access to the high rez timers helps, I can't say by how much. I want to stay away from subjective tests as much as I can. This is because as the MIDI timing gets tighter, I can't hear problems or fixes... so I need something I can measure. I know there are midi events that can be used for time keeping as the old 401 did. They had a so many ticks since the last event thing and when it overflowed it forced an event. This meant the software could always place the note where it belonged not matter how long it took to get to the recorder. I am thinking that hydrogen does the same thing and qtractor records it and plays it back negating the problem with USB MIDI IFs. The only time I have been able to hear the problem has been recording and playing back the demo from an old yamaha PSR synth (read toy with MIDI ports). Unfortunately, the demo seems to have been authored by someone who knew how to swing, so there are not that many on beat notes to look at. I will have to try using the march out of the beatbox part I guess. > However, to play MIDI events by external equipment I'm using jack2's > "-Xalsarawmidi" in combination with a2jmidi_bridge and PCI (Two Envy24 > TerraTec 24/96)/PCIe (RME HDSPe AIO) MIDI interfaces only. I'm not using > my swissonic USB MIDI. I don't normally use USB MIDI either. In fact I bought this one for testing MIDI timing and perhaps to use it a bit on my netbook (USB only). I am not much of a KB player, Like Holstein, I am mostly a Bass player, though not his caliber for sure. > Don't disable your ac97, perhaps it ships with a parallel port MIDI that > might be good. Unfortunately my machine don't has parallel port MIDI. As far as I know, my ac97 has no MIDI, certainly no MIDI modules load when it is the only audio IF active. I am instead using the game port of an old ensoniq card which seems to be very stable, even with cheap synth input. It is a 401 "compatible" IF. > Btw. are you subscribed to > https://lists.sourceforge.net/lists/listinfo/qtractor-devel ? Nope, I will keep it in mind, right now I am having trouble keeping up with this list and LAU (which I still haven't managed to post to yet). -- Len Ovens www.OvenWerks.net -- Ubuntu-Studio-devel mailing list [email protected] Modify settings or unsubscribe at: https://lists.ubuntu.com/mailman/listinfo/ubuntu-studio-devel
