> For the device in question, Griffin iMic, this doesn't seem to be the > case. It does not separate enumerations for independently setting left > and right input gain. It does support stereo input, just not two > mic/line gain controls.
I don't know about the iMic - Chen would though. We've been using TI and Micronas USB sound devices that are directly supported by the native "Windows Audio." The TI devices do not have an input mixer - sounds a lot like the iMic - but they still provide two channels of receive audio and an application can hook either channel or force the driver into mixed mono. I've used both the TI and Micronas based devices in stereo (separate left/right) for dual receive or right only (sub RX only) with MMTY, MMVARI, and MixW. Unfortunately, I see the issue with FLdigi ... it uses mixed mono with either the TI or Micronas CODECs. I can handle that by turning down the input level to the CODECS (manual gain controls) but that still does not permit dual receive. Interestingly, DM780 handles both the TS and Micronas in left channel (Main RX) only. 73, ... Joe, W4TV > -----Original Message----- > From: Leigh L. Klotz, Jr WA5ZNU [mailto:[email protected]] > Sent: Saturday, January 31, 2009 7:51 PM > To: [email protected] > Cc: [email protected] > Subject: Re: [Elecraft] K3 LINE Out mixes KRX3 and main output? > > > Joe Subich, W4TV wrote: > >> It doubles the data transfer to capture both sound channels > >> and discard one. > >> > > > > Why would you bother to capture both? Your software should > > be able to select left, right or mixed input from the soundcard. > > > > Hmmm...I'm looking at the multi-platform PortAudio v19 API here: > http://www.portaudio.com/docs/v19-doxydocs/structPaStreamParam eters.html Currently, we're using PaStreamParameters::channelCount=1, which doesn't offer the opportunity to specify a left or right. With channelCount=2, we could of course get two channels and discard one, as I mentioned. PulseAudio, which is Linux only, doesn't seem to support it either, but I believe ALSA and OSS do. So, if we use a Linux only solution it's possible to specify single-channel capture without discarding one channel, but for the cross-platform APIs, it doesn't seem possible. I know you know more about sound device manufacture than I do, so maybe you can point us at something we've overlooked in PortAudio, so at least we could get portable sound capture support for single-channel input. > Even relatively basic USB sound codecs provide control over the > input configuration. > For the device in question, Griffin iMic, this doesn't seem to be the case. It does not separate enumerations for independently setting left and right input gain. It does support stereo input, just not two mic/line gain controls. This seems to be the case on Linux (see http://seehuhn.de/pages/imic ) as well as Vista. On Vista, it's even worse, and won't capture in stereo at all. Leigh/WA5ZNU ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
