Fons: Thanks for your suggestions and input. Here is are some more outputs from a different dynex dx-sc51 soundcard: http://nielsmayer.com/npm/jaaa-db50xg-L-fullband-captureoff.png http://nielsmayer.com/npm/jaaa-db50xg-L-fullband-captureon.png http://nielsmayer.com/npm/jaaa-db50xg-L-lowfreq-captureoff.png http://nielsmayer.com/npm/jaaa-db50xg-L-lowfreq-captureon.png http://nielsmayer.com/npm/jaaa-db50xg-R-fullband-captureoff.png (note interesting anomaly at ~14K) http://nielsmayer.com/npm/jaaa-db50xg-R-fullband-captureon.png (anomaly disappears in the noise) http://nielsmayer.com/npm/jaaa-db60xg-R-lowfreq-captureoff.png http://nielsmayer.com/npm/jaaa-db50xg-R-lowfreq-captureon.png Capture on vs capture off on the soundcard shows a big difference in the noise floor. Is the -62db/hz&-66db/hz at 0.1hz an anomaly? In 'jaaa' the 0.1 hz value "jumps around" as if there were a shifting DC level. It can be seen in 'yass' for example... "capture off" shows a flat line with AGC turned on. "capture on" shows a noise that is entirely positive voltage, which can be raised higher by adjusting the capture gain above 0db. Thus the purchase of a used $20.00 soundcard to replace this $0.99 one. You gets whatcha pay for... Niels http://nielsmayer.com _______________________________________________ Linux-audio-user mailing list Linux-audio-user@xxxxxxxxxxxxxxxxxxxx http://lists.linuxaudio.org/listinfo/linux-audio-user