convertion drastically slows down (why?)

[g73]

Hi,
when I convert a wav track to mp3, the first 50% of it takes about 15sec' and then it drastically slows down (about 3 min' for the second 50%).
Does anybody have an idea why does it happen? and what can be done?
Thank's,
g73

[ChristinaS]

Re: convertion drastically slows down (why?)

This may be due to the Volume Normalize function combined with a slow processor and memory. Also it depends to what bitrate you are encoding and whether it is Constant or Variable or average.

I just tested a 50MB wav file converted to 128kbps mp3: it took 29 seconds, with the first 4 seconds doing the first 50% of the conversion and the remaining 25 seconds doing the other 50%. Converting to 64 kbps was done in 21 seconds, with similar distribution of the conversion process. Converting to 128 kpbs VBR, highest quality took 44 seconds, with an even more skewed process: 4 seconds for 50% and 40 sec for the other 50%. For 64kbps, VBR and highest quality, plus CRC checksums, it took 1m21s, in all, with most of that time spent in doing the second 50% of the conversion.