I have a CD that has sine waves, and I ripped to my pc using WMA format. When I played low frequency sine wave back (I think it was 20Hz), it sounds totally wrong. Volume level fluctuate a lot as if someone turnning volume up and down. I ripped again with highest bit rate. It still happens.
I thought sine wave is the easiest to compress. It happens low freq. sine waves only. High freq. sine waves don't have that behavior. I am guessing one of following could be happen.
- Sine wave on the CD was not a perfact sine wave.
- codec compress too much on low freq. because human can't hear well.
- codec error.
Do anyone know what can cause this?
I thought sine wave is the easiest to compress. It happens low freq. sine waves only. High freq. sine waves don't have that behavior. I am guessing one of following could be happen.
- Sine wave on the CD was not a perfact sine wave.
- codec compress too much on low freq. because human can't hear well.
- codec error.
Do anyone know what can cause this?