Tom186;649217 Wrote: > Most certainly. Is it going to run with Async USB at all? No luck with > my current setup (an Arcam rDAC with USB), with any of the current USB > Audio solutions out of the SBT, including the one in soundcheck's tools > and the one John Swenson proposed. > > Best, Thomas
I've been working on the USB DAC issued again this week, its getting better but still not perfect. There are a couple different issues, most of which relate to 24 bitness not async per se. One issue is that most USB DACs that use 24 bit use a different 24 bit format than the The Touch uses, this requires you use the PLUG interface, which adds an extra layer and messes things up. I have a custom jive_alsa which supports the other 24 bit format, which allows you to not use PLUG, this helps a lot but isn't perfect, I still get occasional clicks and pops. I have been playing a lot with thread priorities and can significantly change the pattern of clicks, but so far I have not been able to get rid of them entirely. Another thing that helps is the udev script that was posted here a while back, this makes sure that the USB DAC winds up with the same card number. Unfortunately it doesn't go far enough and sometimes it can still wind up in conflict with existing devices (S/PDIF or one of the two DACs). This can cause some issues as well. I need to get some time to revamp the udev script so it handles all sound devices and makes sure all devices are always unique and the same name. I don't think its hopeless, sometime we will figure out how to get modern USB DACs to work well with the Touch. I don't think its a driver issue, the existing one does seem to handle async properly, it seems more like its interrupt priority/latency issues more than anything else. Its actually very dependant on what else is going on inside the Touch, so all the stuff Soundcheck has been working on helps a lot. I just think I have not found the right combination of priorities and buffer sizes etc. The interesting thing is that when I go back to 16 bit mode everything works fine, no clicks or pops, but the moment I turn on 24 bit mode, problems start happening. IF your DAC supports 16 bit, and you are listening to 16 bit music, and you have the volume set to 100 then there should not be a problem going to 16 bit mode, BUT a lot of modern DACs will not run in 16 bit mode, which means I need to get this figured out. John S. -- JohnSwenson ------------------------------------------------------------------------ JohnSwenson's Profile: http://forums.slimdevices.com/member.php?userid=5974 View this thread: http://forums.slimdevices.com/showthread.php?t=84742 _______________________________________________ audiophiles mailing list [email protected] http://lists.slimdevices.com/mailman/listinfo/audiophiles
