19 Nov
2008
19 Nov
'08
9:16 p.m.
On Wed, Nov 19, 2008 at 5:16 PM, Matthew Smith <matt(a)smiffytech.com> wrote:
Hi Folks
Whilst my 2.6.24.7-rt17 kernel and disabling all hardware and services
unneeded for audio seems to have gotten rid of those nasty xruns, I live
in fear that they will return. My main worry is how I organise my USB
devices.
My laptop (ThinkPad Z61m) has 3 USB ports. I have several devices that
need to be connected to them, meaning that I need to use USB hubs.
Here are some assumptions (or guesses) that I have made, on which I
would appreciate comment:
* It would be best to balance the devices across the 3 ports.
* My soundcard is a Behringer UCA202, capable of sampling at a maximum
of 48kHz @ 16bits x 2 channels. I'm guessing that this will have the
greatest data rate of all attached devices.
- Should it have its own port?
Yes. This will probably use more bandwidth than all the other devices combined.
- Can USB 2.0 take more than this (like another
device?)
No USB 2.0 audio devices have Linux support AFAIK.
- Anyone know how to set the sampling rate on this
device through
Linux? Just specify in Jack setup?
Should work.
* Now that I know that I can run USB to MIDI devices
through a powered
hub (thanks David), I was thinking of of hooking the following into a
7-port hub:
- iPod cable (no iPod on the end, so no burden.)
- cellphone cable (as per iPod cable.)
- external USB QWERTY keyboard (don't have desk space for this
when doing audio work, so hope it won't be transmitting any
data.)
- trackball (only transmitting when wiggled (I hope) - which should
not occur when recording is going on.)
- USB floppy drive (not in use when recording.)
- USB to MIDI interface
- Another USB to MIDI interface - is it too much to have 2 of
these on the same hub? If not, would it take a third?
MIDI uses very little bandwidth, should work fine.
Lee