Sound card perfomance at different sample rates Reply #50 – 2014-02-22 19:08:58 Quote from: YellowOnion on 2014-02-22 10:22:24My Xonar DS has terrible ultrasonic performance, I get an audible tone near the 4-5k area if I play a ~44kHz sinewave http://i.imgur.com/zu9Kevt.pngThe internal DSP (all settings, 44.1/48/96/192 same result) must lack any sort of anti-aliasing on its LPF, though why it applies a LPF in the first place, I have no clue.I make sure I have Windows set to 48kHz as it has a functional LPF for the rare occasion I ever come across high sample rate content.I think your card is probably running at 48KHz in that picture (note that it aliases about 48k/2Hz), and what you are seeing is just a resampler from whatever sampling rate your sweep was at to your cards actual sampling rate.FWIW, I don't think that plot looks all that bad. Playing a pure, full scale ultrasound tone just a hair below the sampling rate of a sound card will generally introduce artifacts unless the resampler is very, very slow. Its almost impossible to +100dB of rejection very close to the Nyquist rate, so a pure tone at that point will generally be audible. Doesn't matter in practice though, since no one masters real audio huge massive amounts of power 40KHz+. You'd risk blowing out people's tweeters.