Hi,


Downloaded a couple of my favorite songs from a music site (MP3 at 128 bit over cable/dsl, and T1 & T3 at 128). But I find that Windows XP media player doesn't play them at the same loudness as the default sample songs you get with the Windows OS cd. Why is that? Do all/some music sites degrade their music in some way? Is their some way to fix this kind of problem so all songs play at a reasonably similar sound level? I also find that some internet music stations degrade their music quality intentionally so you'll purchase the higher quality feed. Is their a fix for this problem?


Thanks in advance,
Lu

Lower quality files can't be improved as to the sound quality (kinda like the old adage - 'You can't make a silk purse out of a sow's ear'). But, you can run the files through a 'Normalizer' to get the volume levels equal. You can download a free one here.

I know this is over a month old now, but to add to this ....

MP3 compression is what is called lossy compression; when the music data is compressed, psychoacoustic techniques are used to remove anything the ear is deemed to not be able to pick out.

The algorithm allows for degrees of flexibility in this, so you can compress at a lower rate (thus resulting in a larger file but good sound quality) or a higher rate (smaller file, poorer audio quality).

If it's a smallish file, then chances are the compression ratio will be quite high thus resulting in poorer sound quality.

However, as Jim said, you can normalise the volume, but this will not improve the sound quality because information that has been removed cannot be replaced without resorting to the original.

Hi Angus,
This is so interesting. Just for my information, I wanted to clarify a few points....I have come accross softwares which convert mp3 music to audio cd formats [eg. Nero]... the files thus created are considreably larger than the original mp3 files and I feel that some quality enhancement also takes place[ I may be wrong...]... now what goes on in here? How is the audio quality enhanced? Does quality enhancement really occur or is this another way of cosmetic enhancing what ever data is available in the mp3 file [ I mean to a layman, is it something similar to picture results of digital zoom vs optical zoom in photography]? I'll be grateful for more information on this.
Thanks,
Sun

No, it's just uncompressing the file into raw (.wav) audio to allow it to be read by audio CD players.

Using your Photograph analogy, it is like cropping and enlarging - say you have an 8x10 digital photo and crop to only show the bottom right corner 4x5.
You have lost the other 3/4 of the image.
Now you enlarge the 4x5 to 8x10 size.
You'll get:
a) A poorer quality image (more pixelated)
b) A bigger file than the cropped 4x5 but with less data than the original 8x10.

Hi Smurfy,
I get your point..... data lost in compression to mp3 is kind of "lost for ever" ....
I feel more informed now,
Thanks,
Sun.