Hi,
jpo234(a)netscape.net wrote:
Patrick,
thanks for your quick reply. I'm not quite sure whether your answer
is really the answer on what I wanted to ask, so I'll clarify below.
Patrick Shirkey <pshirkey(a)boosthardware.com> wrote:
Your be either one rme hammerfall + digital mixing
desk with adat
connectors. Otherwise you can use multiple cards but they need to be
wordclock synced so you tracks stay in sample sync with each other. In
that case you could use two rme hdsp multifaces, 2 midiman delta1010s
and there are a couple of other 8 i/o cards with ALSA support.
I think to make sure that this is really what we need I'll have to
provide a better description of the problem. We are developing a
testbed for wireless voice transmission. We will have up to 16 active
phones, that are independently used to receive voice samples.
Having implemented a tool very similar to this I'd say Patricks
suggestions are pretty much correct.
Back then the only viable alternative was RME Hammerfall 9652. I think
it stands as a good alternative today also.
Our solution was built to handle 72 channels (three hammerfall cards)
and did it's analysis in realtime. As it happens we never went above 24
channels (one card), but that worked rather well.
This was before jack so it was interfaced directly to alsa. If we where
to redo it today I think we would have used Jack however.
We have
to record each voice transmission to a .WAV file (because this is what
the quality measurement tool understands).
To do this we will have to connect the 16 phones to a Linux box (prefered)
and need the ability to save the voice sample to a file. Each sample is
completely independent of all the other samples. Basically we need the
ability to do "sox /dev/phonespeakerX phoneXsample.wav" where 0 <= X <=
15.
Since it seems you are mainly interested in creating WAV files, there
may be a possibility to create a solution with of_the_shelf tools.
I'm mainly thinking of ecasound.
I'm not sure if it can handle the throughput but I think it would. Quite
easy to find out anyway ;)
Regards,
Robert
Will we
have 16 /dev/dsp devices [e.g. /dev/dsp0 .. /dev/dsp16]?
If you use jack you will have an easy to understand interface for
routing the i/o's.
Following your suggestion I glanced at jack. I'm not quite sure whether
this is really what we are looking for.
Thanks in advance
Joerg