Recent content by phofman

Yes - e.g. the documentation https://www.roomeqwizard.com/help/help_en-GB/html/calsoundcard.html#multichannel

Did you try Wasapi exclusive (the JAVA -> EXCL: devices) instead of the ASIO4ALL workaround?

It looks MS messed up something around their USB stack, breaking flow of isochronous transmissions (people seem to complain about webcams etc.). Probably just a temporary situation, it is a major issue as modern motherboards increasingly use onboard USB audio instead of HDA.

IMO this issue is not related to REW, but to the way a DSP application is being run on the gadget side of the USB link. Windows mixer and REW use whatever rate the gadget audio device is configured to support. But the DSP application on the gadget side must be able to respond to the gadget rate...

Please see the first paragraph of https://www.roomeqwizard.com/help/help_en-GB/html/calsoundcard.html#audioconfig

@John Mulcahy : Do the mdat serializations contain the actual recorded stream?

The chart at https://www.avnirvana.com/threads/rew-measurements-problem-with-slow-pc-laptop.14573/post-111536 suggests exclusive at 16k, with the peaks. What was changed afterwards that it's ok now?

Well, it's possible you are getting buffer glitches. But they would likely not occur always at the same moment of the sweep (like at 3kHz with the 256k buffer), the timing would be more or less random, as the OS does not keep up. Unlike buffer glitches caused by ASIO merging the two devices -...

I would recommend to keep using wasapi exclusive (EXCL), to eliminate the potential issue with duplex ASIO to two different audio devices.

Do you use wasapi exclusive (i.e. selected in REW https://www.roomeqwizard.com/help/help_en-GB/html/calsoundcard.html#audioconfig ) for that measurement?

Does it happen with both capture and playback using java exclusive in REW too?

Flexasio merges two soundcards with independent clocks into one callback. IMO technically that is not correct, and works ok only due to short measurements sessions where the buffers do not have time to go apart. IMO the asynchronous Wasapi exclusive is the proper API for this.

@lfdm: I wonder why the pipewire GUI shows only 2ch for the Pipewire Alsa connections, eventhough the REW/java alsa interface should open the alsa PCM pipewire device (= alsa plugin...

ASIO drivers themselves are not flawed, but the ASIO adapters which merge different capture and playback devices are. ASIO passes data for both directions using one callback method bufferSwitch with fixed buffer size for playback and capture. It means it expects both directions to be clocked by...

Using different devices for capture and playback in ASIO (be it ASIO4All or FlexASIO) is flawed by ASIO design and if it happens to run OK, it happens by pure chance that the two devices have clocks running at very close frequencies. The technically correct interfaces are java (WDM via windows...