On Tue, 27 Apr 2021, at 19:45, didier gaumet wrote: > I might be wrong (I don't mix nor record) but I think there are two > distinct problems: > > a) the wav file you generated is not supported by ecasound because its > type (codec) is neither (L)PCM nor IEEE_FLOAT > https://en.wikipedia.org/wiki/WAV > So, either you produce a wav file encoded in LPCM to use ecasound, or > you use another tool than ecasound that supports the codec you used to > produce your wav file
I'd want to use some other tool - "sox" perhaps - to verify that the file really does contain three channels of audio. Can, say, the three channels be selected one at a time and played back without using the Behringer box? I'd also need to be convinced that the alsa part of the command that someone posted did actually access the correct channels and try to send them somewhere. I'd probably want to try to use something else - maybe "sox" - to send test tones to three named places (as far as alsa is concerned) on the PC before trying to find out which of those arrived properly at the audio interface. > b) https://mediadl.musictribe.com/media/sys_master/h7e/hfb/8849567252510.pdf > your audio interface is a stereo one: it has only two channels (Left > +Right) as outputs. I'm not sure that's true; look at https://d1aeri3ty3izns.cloudfront.net/media/25/259085/download_259085.pdf (which is the second pdf linked to from https://www.gear4music.com/Recording-and-Computers/Behringer-U-PHORIA-UMC404HD-Audio-Interface/1WMY?gclid=EAIaIQobChMIheDYlJKf8AIVgQWiAx0ldgK6EAAYASAAEgI13fD_BwE ) which clearly states that the box can stream 4 inputs / 4 outputs. The PDF you linked to is one of those very annoying manuals that describe many different units, and it's very hard to understand what any single unit can do. Worse, there's no schematic showing where signals can flow to & from. I also looked at an Amazon listing for the box, but it had the same problem - people's comments applied to various different models. Although it does seem to support 4 separate outputs, these might be just copies of the signals supplied on the 4 mic/line inputs (so if one was using this box to record a couple of singers and guitarists - ie 4 inputs in all - copies of those signals could be played back to the performers). On the other hand there's a MIX control which appears to change how signals coming from the 4 inputs are mixed with those (from a PC?) that are being played back. Maybe if that's turned all the way to the PB position audio channels from the PC would be directed to the playback outputs? > Even if there are 3 groups of output, they all play > the same thing, a stereo signal. I think that's true of the "MAIN OUTPUT" but I'm not sure it also applies to the "PLAYBACK OUTPUTS". > As a sidenote: are we speaking of the same thing? Inputs are called > tracks. You could for example have 4 mono tracks for a rock band > (1:singer, 2:guitar, 3:bass, 4:drums) and each of these tracks are mixed > and panned to 2 outputs (Left and right) that are called channels. This unit has no pan controls, so panning the 4 inputs to positions on a stereo image must be something done by mixing software on a PC. That makes the buttons that refer to stereo/mono more confusing, as the box itself has no concept of stereo. Does it follow that the box sends 4 inputs to a PC, and the PC might send back either/both copies of those 4 inputs and a mixed stereo image? -- Jeremy Nicoll - my opinions are my own.
