[LAU] In Search of The Unicorn

[Clemens Ladisch]

Ken Restivo wrote:
> On Mon, Nov 08, 2010 at 10:13:04AM +0100, Clemens Ladisch wrote:
> > Ken Restivo wrote:
> > > 3) Has FOUR outputs and 2-4 inputs, all usable from within JACK, with
> > >    good professional quality DAC/ADCs.
> > 
> > This would mean full duplex and 24-bit samples, which would exceed the
> > bandwidth available for full speed devices.
> 
> That seems odd, since there seem to be a lot of very cheap USB 1.0
> devices that can support 6 channels (5:1 surround for home theater).

Full speed has just barely enough bandwidth for eight channels of 16-bit
samples at 48 kHz.  This could be 7.1 output, or 6 outputs + stereo
input, or 4+4 outputs/inputs.

With 24-bit samples at 48 kHz, there's bandwidth for five channels
overall, i.e., 4 output channels, or full-duplex stereo.

With 24-bit samples at 96 kHz, there's bandwidth for two channels,
i.e., stereo output _or_ stereo input.


Regards,
Clemens