Hi Paul, thanks for the quick answers, I tried things as soon as I got back. I've been experimenting some more (sometimes analogue audio is so much easier to debug), and I'm slowly learning stuff, but I haven't been able to actually record things yet. So, on to some more questions ... That seems to work as you says it does (apart from the fact that I can't verify it actually works yet :)). I haven't seen this in any of the ALSA docs I read through (granted, most of those were updated and seemed to be pre-0.9, so I can't even tell how relevant some of those docs are) - did I miss some more important document, or a most recent version of it ? Or did I just miss it in my eagerness ? After connecting S/PDIF input to the two cards, I wanted to try and record stuff to see if I actually got the signal in. I'm using arecord with various options. arecord -l gives me [root@framboos tmp]# arecord -l card 0: 15 [RME Digi9636 (Rev 1.5)], device 0: RME Digi9636 (Rev 1.5) [RME Digi9636 (Rev 1.5)] Subdevices: 1/1 Subdevice #0: subdevice #0 card 1: 15_1 [RME Digi9636 (Rev 1.5)], device 0: RME Digi9636 (Rev 1.5) [RME Digi9636 (Rev 1.5)] Subdevices: 1/1 Subdevice #0: subdevice #0 arecord -L gives me a whole lot of output to stderr which I can't fully understand at this point. -d should allow me to specify a device, but I have no idea in what syntax this is for which card. I tried a few things: - specifying 0 and 1 - specifying 15 and 15_1, the card ids - specifying "spdif" (based on output of arecord -L, but I don't know how I would choose between cards in that case) - specifying random numbers, which seems to do something even though I can't imagine what it would be recording from in those cases. In some cases it terminates after a second, which probably means I specified an invalid device, but I don't get errors. I have run with -v as well, but that seems to give information about internal (software) plugins to do the recording. All of the files I recorded I encoded with oggenc as a quick hack - if the bitrate is 0.8 kb/sec, I'm pretty safe in assuming that I recorded silence :) So basically, my questions are : a) is there some alsa-enabled recorder that allows me to choose devices easily and allows for monitoring the incoming signal ? b) what is the correct way (or a doc describing it) to specify devices for arecord ? Is arecord using the "ALSA-standard" way of doing this, as is done in other applications ? c) could I have forgotten anything else here when trying to record stuff ? I assume that, since the Hammerfall doesn't have a mixer chip, the channel is always-on. If there isn't any Hammerfall quick how-to, I wouldn't mind writing my experiences down if that could be helpful for anyone. Thanks in advance, Thomas -- The Dave/Dina Project : future TV today ! - http://davedina.apestaart.org/ <-*- thomas (dot) apestaart (dot) org -*-> Now I find myself redeemed 'cos no one's seen the bad in me or been where I've been <-*- thomas (at) apestaart (dot) org -*-> URGent, the best radio on the Internet - 24/7 ! - http://urgent.rug.ac.be/

Hi Paul, Ok, so this is probably associated to the output of arecord -L then, which seems to be listing all "plugins" that can be used as pcm input ? I think I'm starting to understand slowly. Is there some doc explaining output of arecord -L a bit more so I can follow what goes on, or is that an ALSA-specific question ? Ah, didn't know that - so you are saying that whatever you record, it always record 26 mono tracks at the same time ? So how do I tell arecord I'm only interested in the stereo S/PDIF signal coming in on ADAT1 ? I'll probably end up doing one in GStreamer for diagnostics purposes. I'd imagine ALSA is great once it's set up correctly, but the setting up correctly bit is killing me. Ok, so this is in addition to using the known set of plugins, as described above, right ? I have the feeling that arecord should warn about incorrect device specifications, is it just not doing that or is there some reason not to tell the user that the device string is probably wrong ? I'm asking about the correct way of device naming so that I can make sure that we (GStreamer) do it in the canonical way, because none of us is entirely sure about the right way of specifying a specific channel on a specific card using alsa. Something very simple - at first just trying to record an incoming S/PDIF signal coming from a DAT tape. I've been recording with arecord and encoding with oggenc, because I know that oggenc uses very little bitrate when the signal is zero. So that's my hacky test for "do I have incoming signal or not ?" :) As you mentioned in the previous mail, I set my input for ADAT1 to Optical and I set the flag to true, so I must still be missing something else. Thanks for your time, Thomas -- The Dave/Dina Project : future TV today ! - http://davedina.apestaart.org/ <-*- thomas (dot) apestaart (dot) org -*-> I touch and you melt down You don't even know it how much I want to believe it <-*- thomas (at) apestaart (dot) org -*-> URGent, the best radio on the Internet - 24/7 ! - http://urgent.rug.ac.be/