#WINDOWS AUDIO SESSION VS DIRECTSOUND HOW TO#
#WINDOWS AUDIO SESSION VS DIRECTSOUND FULL#
#WINDOWS AUDIO SESSION VS DIRECTSOUND WINDOWS 10#

The result shows that in the right channel the sub-16-bit information is still present. 96В kHz, MME, Low-Pass FilteredДЄn interesting observation: I filtered the 96В kHz, MME recording above with a 5В kHz low-pass filter. But the source's sample width is 16В bit only. Just for completeness that the interface works here, too. This import is shown here just in order to prove that the interface works correctly.

The recording program used is a very simple test program based on DirectSound. This file is imported to, but not recorded by Audacity. 96В kHz, Imported WAV-File from a Primitive Self-Written Recording Program

#WINDOWS AUDIO SESSION VS DIRECTSOUND HOW TO#

I couldn't find how to stop that stupid dithering noise, particularly not in Preferences -> Quality. 48В kHz, MMEДЎ6 bit recording only with (obviously) some dithering noise added. The right channel's sine wave amplitude is below the 16В bit quantization threshold but even though it is bit-precisely recorded.

192В kHz, MME, Test Signal 0 to 90 kHz: This test signal was recorded in order to prove that Adacity in MME mode able to work correctly at 192В kHz.

96В kHz, MME, Low-Pass Filtered: Interesting observation: Dithering must have taken place before truncation to 16 bit!.

But the source's sample width is in this case 16В bit only.

192В kHz, MME: Just for completeness that the interface works here, too.

96В kHz, MME: Works, 96В kHz with 16 bit only.

96В kHz, Imported WAV-File: This import, recorded with a different program, is shown here just in order to prove that the interface works correctly.

#WINDOWS AUDIO SESSION VS DIRECTSOUND FULL#

96В kHz, WASAPI: Full failure, nothing to add.48В kHz, MME: 16 bit recording only with (obviously) some dithering noise added.48В kHz, WASAPI: This recording is simply perfect.Afterwarts the 2160 pixel high screenshots were cropped to a reasonable height. In order to make signals below the 16В bit quantization threshold as visible as possible, Audacity's vertical scale was as much as possible expanded on a 3480 x 2160 pixel screen.All project rates set to the actual sample rate.Left channel peak value: 0x0004f5 (-76.40В dBВ FS, 20В dB more than right channel).Right channel peak value: 0x00007e (-96.40В dBВ FS, 6В dB below the 16В bit quantization threshold).Signal source: Two 4В kHz tones, 24В bit, both channels in phase, digitally generated.The problem is that Audacity doesn't want to connect in WASAPI-mode at 96В kHz to the USB interface while at 48В kHz it connects and works perfectly.

#WINDOWS AUDIO SESSION VS DIRECTSOUND WINDOWS 10#

The OS is Windows 10 Professional, the Audacity version is 2.1.2 (all 2.1.x, even a 2.1.3 nightly build have been tested). The 'sound card' is the DA2USB, the Signal source is very special and precise digital audio signal generator. WASAPI Audacity Recordings with MME (or DirectSound) vs. Audacity Recordings with MME (or DirectSound) vs.

Windows audio session vs directsound