jjb@hardy.u.washington.edu (Jim Black) (06/24/91)
Someone wrote on this newsgroup recently that he knew that "the DSP couldn't play and record at the same time". Is this true? I'm not asking whether the SoundPlayer (for instance) will support playing and recording at the same time. Rather, is there anything about the DSP itself that would prevent recording a stereo 44.1KHz signal - while playing another one through the stereo outs? (Assuming, of course, that there's enough disk bandwidth available to read one sound while writing a new one.) It seems to me that the DSP has plenty of power to handle two stereo jobs in realtime (eg, it can play 2x2 44.1KHz tracks via rtmix), but I dunno... -- Jim Black (jjb@u.washington.edu)
laroche@wayne (Jean Laroche ) (06/24/91)
In article <1991Jun24.101635.14514@hardy.u.washington.edu> jjb@hardy.u.washington.edu (Jim Black) writes: > Someone wrote on this newsgroup recently that he knew that "the DSP > couldn't play and record at the same time". Is this true? > > I'm not asking whether the SoundPlayer (for instance) will support > playing and recording at the same time. > > Rather, is there anything about the DSP itself that would prevent recording > a stereo 44.1KHz signal - while playing another one through the stereo outs? > (Assuming, of course, that there's enough disk bandwidth available to read > one sound while writing a new one.) > > It seems to me that the DSP has plenty of power to handle two stereo jobs in > realtime (eg, it can play 2x2 44.1KHz tracks via rtmix), but I dunno... > > > -- > Jim Black (jjb@u.washington.edu) Yes, you can record a sound from the DSP SSI port and play another one on the stereo outs. You just need to set-up two different stream, one from the DSP to the memory, the other one from the memory to the DACs. In fact, it makes it possible to create delays of over 2 minutes, using the main memory: While you record on the memory, you play chunks that you recorded a while ago on some other part of the memory. OK, it's not very useful, but it's fun, it works great, in real time, for 44100 stereo! You just need Analog/Digital converters to plug into your DSP port (something like Metaresearch's Digital Ears, or Singular Solution's A/D64X) I have the source code, if anybody is interested. The one thing you can't do, though, is to play a sound at the very same time you're recording it. That is, you can't listen to what you're currently recording. That's a driver problem, not a DSP problem. Jean Laroche, Paris
shirley@washingtongothamcity (Bill Shirley) (06/26/91)
I can imagine how this would be useful to "test" speaker equipment
for frequency response. You output pure frequencies to the speakers
while inputing the percieved amplitude by your mic. Hmmm...
Or move your mic around the room at several frequencies and test
the acoustic environment of your room. Hmmm..
Or ...
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