Am 01.03.2016 um 11:19 schrieb Tanu Kaskinen: > On Mon, 2016-02-29 at 17:33 +0100, Klaus Jaensch wrote: >> I'm wondering why it is the default to mix the channels. > If there's a device with channel map "front-left,front-right", and a > capture stream appears that has channel map "mono", do you wish that > pulseaudio would by default take audio only from the left channel? Why > would that be more likely what the user wants, rather than taking audio > from all channels the device has, or only from the right channel? Yes. If the user wants only the left channel he has no chance to do so. (Without changing the configuration.) You can't split the mixed channels later. The only way is to record stereo and split the channels later. If you want a mix of both channels it is always possible to record stereo and mix it later. Another problem with mixing is that the level meter of applications like audacity show the amplitude of the mix. If you do not know that the level meter shows only half of the dynamic range (-6dB) if only one microphone is plugged to the left channel it is likely that you overmodulate the recording. And as far as I know it is the default on Windows and Mac OS X to record only the left channel. I've checked this with some of our USB audio devices. Klaus >> I think mixing should be done by the applications, not by the audio >> system. > Surely it's better use of resources to implement mixing once in the > audio server rather than in every single application separately? Also, > if an application wants to be in charge of mixing the audio, it can do > that. Apparently the developer of whatever recording application you're > using didn't bother with that, if it doesn't allow you to pick the > device channel you want to record from. > > -- > Tanu -- ------------------------------------------ Klaus Jaensch Muenchen Germany Institut fuer Phonetik und Sprachverarbeitung Schellingstr.3/II Room 223 VG 80799 München Phone (Work): +49-(0)89-2180-2806 Fax: +49-(0)89-2180-5790 EMail: klausj at phonetik.uni-muenchen.de
