Improving sound quality on mp3's
 

Hey folks...

I'm trying to improve the quality of my mp3's. The software I use for burning CDs has some enhancements on it, but are there other programs out there that can assist in the process?

Are you creating mp3s or converting them to audio cds? I assume the former, but I'm not entirely sure.

Anyway, you could just rip them at a higher bitrate, such as 160, 192, or 256. The software you use to rip them also makes a huge difference in the quality of the mp3s. I recommend RazorLame, or anything else that uses the "Lame" encoder.

You might not want to "enhance" your audio with some of that crap...

I'm converting mp3's to CD. I know there can be some differences in sound due to different producers, but the main problem I'm having is with volume. Maybe that is due to the different bitrates, but I mainly just want to level out the volume on what I have.

There's not much you can do to improve the sound of a poorly-encoded mp3. Where did you get them from? If you ripped them yourself, try re-ripping with higher bitrates. If you got them off the net, try finding them again at a higher quality.

Yep, that's pretty much it. I think there is something you can do to adjust the volume levels, but I've never done it before so I don't know anything about it.

There is normalization, which is an attempt to set volume levels at roughly the same place. The effect of this is to force all songs to roughly the same volume level no matter what. This is a nice idea for some purposes, but I don't use it at all myself. Reasons:

- I prefer to respect the original mastering engineer's decisions because I think they may know than me.

- Especially in an album context, the volume levels are part of the original content and should be preserved for artistic reasons.

- It may screw up the original. By converting to mp3 (or OGG, WMA, AAC etc), we are already reducing the quality of the sound. I don't know how "lossy" normalization is, and buggy code can mess it up anyway.

I think I have found the solution to my problem...

I took one of the funny volume songs (a ripped mp3), put it into Nero, and pulled up the wave editor to view the sound spectrum.

I then ripped a song from a CD and did the same thing.

I noticed a significant difference between the two graphs. So, I bumped up the volume on the "quiet" song by 11 decibles, to bring it up as close to the CD song as possible.

What a difference. No noticeable difference in quality at all, but better volume. Very impressive.

I understand what you're saying, UT. But as I see it, this was a song that just had a low volume to it, due to a low bitrate, the fact that the song was released in the early 70s and not remastered, whatever. If anything, bumping up the master volume to the song does it justice.

This whole thing has me fascinated. It makes me wonder what I could do with other stuff that doesn't sound right to me.

For example, Nitzer Ebb's Ebbhead album. Alan Wilder and Flood did the production on it. And it doesn't sound bad...but the volume just sounds too low. The CD came out in 1991, so it would have been mastered to CD upon its release. I don't know if they just fucked up the volume controls, or if I got a shitty copy of it, or what.

In general, I straddle the line between preservation and knob-twiddling. There are some things I don't mind on a CD of an older record: the crackle of old tape reels, some background noise, etc. But I want to make the music "fuller"...more alive. Sony did a great job with this on the Miles Davis remasters. A lot of the crackling and splices are gone, but now it sounds like you're right there in the studio, smoking a Marlboro with Miles...and this is stuff that came out 40-50 years ago. Amazing.

A wonderful program I use to normalize MP3's is MP3Gain. It uses a feature of the MP3 standard that lets a certain gain in increments of 1.5 dB to be specified in the header. This means you can adjust it without affecting the actual music data, and can set it back later so that the file is exactly the same as it was at first.

It scans the entire track to determine its overall loudness, then adjusts the header accordingly. You can also specify that it adjusts a group of files without affecting their relative volume to each other, for cases where some songs on an album are supposed to be quiet.

I always give my MP3's a run through this program to avoid having to adjust the volume on my portable player each time a new track comes on.