Hi there, As you might know, having read my previous postings, I'm using an RME digi96/8 card. Since I still have trouble using the ADAT mode - it gives an anoying click train - I setup four very simple tests. Can anybody help me explain the outcome?
First of all I have to give (as root): > modprobe snd-card-rme96 Then, I try four possible ways of playing out a wave file: > aplay -D hw:0,0 stereo.wav works (s/pdif) > aplay -D hw:0,1 stereo.wav error (see below) > aplay -D plughw:0,0 stereo.wav works (s/pdif) > aplay -D plughw:0,1 stereo.wav works (ADAT) *NOISY* 0,0 means using the s/pdif channel 0,1 means using the ADAT channel hw means using the hardware layer plughw means using the software layer (I understand that in s/pdif mode coaxial and optical connectors carry the same signal, so I use optical only, since I can switch my DA convertor between s/pdif and ADAT reception) The resulting messages: Playing WAVE 'stereo.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo Playing WAVE 'stereo.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo play: set_params:724: Channels count non available Playing WAVE 'stereo.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo Playing WAVE 'stereo.wav' : Signed 16 bit Little Endian, Rate 44100 Hz, Stereo So this leads me to the conclusion that the plughw layer converts the audio to 'fit' 8 channels and does a nasty job. Results are similar with 48000 Hz audio. I still have to repeat the second test with an 8-channel wave file... Let's redo the test with ecasound. ecasound -o alsa,hw:0,0 -i stereo.wav works (s/pdif) ecasound -o alsa,hw:0,1 -i stereo.wav works (s/pdif)! ecasound -o alsa,plughw:0,0 -i stereo.wav works (s/pdif) ecasound -o alsa,plughw:0,1 -i stereo.wav works (s/pdif)! the resulting message (four times identical): - [ Chainsetup/Enabling audio inputs ] -------------------- (eca-audio-objects) Audio object "stereo.wav", mode "read". (audio-io) Format: s16_le, channels 2, srate 44100, interleaved. - [ Chainsetup/Enabling audio outputs ] ------------------- (eca-audio-objects) Audio object "alsa", mode "write". (audio-io) Format: s16_le, channels 2, srate 44100, interleaved. - [ Engine/Init - mixmode "simple" ] ---------------------- - [ Engine/Exiting ] -------------------------------------- Apparently ecosound doesn't care much about the device number (would this be a bug?). (I know chain setup with ecasound is very flexible, but if it doesn't recognize the ADAT device in the first place, what's the use?) Greetz, Janroel -- ________________________________________________________________ | | Janroel Koppen, (+31)(0)15-27.86224 | Information & Communication Theory Group, | Delft University of Technology, The Netherlands | [EMAIL PROTECTED], www-ict.its.tudelft.nl/~janroel |_______________________________________________________________ _______________________________________________ Alsa-user mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/alsa-user
