Asus Xonar STX ii - No info above 22KHz

I’ve recently installed an Asus Xonar STX ii. Machine runs Xubuntu 16.04 and Windows 10. Using Audacity 2.1.2 in Linux or Adobe Audition 1.5 in Win10, I see a sharp cutoff of info at 22KHz. Even when selecting 96000 or 192000 project rate, the audio cuts off as if the card’s A-D converter is sampling at 44.1. I did not see that with the M-audio Delta Audiophile 96 that was previously installed. “file” command on wav output confirms proper sample rate in file format.

Could this be a configuration issue, known driver limitation or is the Asus card not operating according to spec (which claims recording rates to 192000)?

Deviceinfo and screenshot of spectral analysis attached.
deviceinfo.txt (6.26 KB)

What sample rate is PulseAudio running at?
Also I’m wondering why you want to record frequencies above 22 kHz.

How can one find the Pulseaudio sample rate?

It’s configured in pulse-daemon.conf
but it would probably be better to bypass Pulseaudio altogether. You can do that by selecting the appropriate “hw” options for recording / playback devices in the device toolbar.

Thanks for the assistance! I was not able to change the behavior by changing Pulse defaults, however, by bypassing Pulse and recording straight from hardware, initial experiments look like I’m getting what I want.

As to why I want to record above 22KHz: I am remastering my personal vinyl collection - I have a few obscure records that are still not out there in digital form. I’ve found that clicks and pops generate significantly more HF energy than the recorded info. This makes it easy to see even low-level clicks that might not be audible in casual listening or with but stick out like a sore thumb when played through a good stereo setup. Impulse noise has absolutely no relationship to the “stereo image” and even low level clicks are particularly disruptive.

Good answer :smiley:
For recordings of real instruments, there is likely to be virtually no audio above 20 kHz (hardly any “audio” microphones extend much beyond 20 kHz), so whatever is present above 20 kHz is almost certainly due to some sort of “interference” or “damage”. Even if you record at 44.1 kHz sample rate, low level clicks will often show up clearly by looking at the frequency range above about 16 kHz, though I appreciate that some may show up even more clearly above 20 kHz.