[tsyoo]

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?

 

[Ethan Winer]

I've compressed sine waves to MP3 files many times with no problems. Never tried WMA, though I can't see why that would be any different.


--Ethan

 

[trekguy]

Assuming that you have a good sub and that you are comparing the sound against the original CD & player curiousity drove me to try it with test tones and a sweep on a CD I have. I did not hear the problem. Of course I can barely hear 20 Hz.

I find WMA to be an excellent format. I am not much given to CD ripping but my wife is and she prefers WMA on here Zune to MP3--IPOD users can only wish for better quality.