Ah, I think I know what it probably is. The old Yamaha DX7 keyboard synthesizer used to have a similar problem.
Basically, the Music 500 has a very primitive DAC, which doesn't cut off at 20KHz. Most likely, it is giving you a spray of high harmonics that are aliasing against the sample rate of the ADC in your sound card (which itself probably doesn't have a very good low pass filter). Playing the same sound through your sound card won't cause the problem, because the audio is mixed in analogue form so the ADC doesn't play any part.
Try stringing one or more ferrite beads on the audio cable, or using a ferrite ring and winding the cable through it a few times. It's a bit of a crude solution, but it often works wonders in these cases.
(listens to mp3 to check)
Yes, that's definitely it. What you have there is definitely NOT hum, it's aliasing noise.
no subject
Date: 2006-07-09 07:00 pm (UTC)Ah, I think I know what it probably is. The old Yamaha DX7 keyboard synthesizer used to have a similar problem.
Basically, the Music 500 has a very primitive DAC, which doesn't cut off at 20KHz. Most likely, it is giving you a spray of high harmonics that are aliasing against the sample rate of the ADC in your sound card (which itself probably doesn't have a very good low pass filter). Playing the same sound through your sound card won't cause the problem, because the audio is mixed in analogue form so the ADC doesn't play any part.
Try stringing one or more ferrite beads on the audio cable, or using a ferrite ring and winding the cable through it a few times. It's a bit of a crude solution, but it often works wonders in these cases.
(listens to mp3 to check)
Yes, that's definitely it. What you have there is definitely NOT hum, it's aliasing noise.