“I‘m using a Digi 001 system on a Mac G4 and a CD-RW drive with Toast. Since getting the Digi 001, I have used it to mix and clean up various cassettes and eight-track reel-to-reel recordings from my pre-digital days. I’ve put all this stuff on CD and it’s worked great except for one thing. When putting songs from a variety of sources onto a CD, how do I make it so the levels of the songs on the CD are approximately equal? As it is now, some songs are quite a bit louder than others. Is this something I should be dealing with when I bounce the songs to disk in Pro Tools? Or is there a plug-in (compression or limiting on a master fader?) that I can set so each song comes out at about the same average level? Or is this something I can do in Toast before burning the audio files onto the CD?”
What you are referring to is basic mastering here, and there are degrees to how far you want to take this concept. Once you get the songs at approximately the same level do you then want to do other things to make them sound more congruous? Just food for thought. You will see that there is no one answer for this question.
Some CD burning programs that make true audio Red Book CD’s (MasterList and Jam, for example) will let you edit the levels of songs right before burning the disc, which is handy because you can make quick comparisons between the various songs once you have them in order. If you use Toast, or any other CD writing utility that simply writes files to disc you will not have that option. But don’t despair. It’s really not that hard to do it on the Digi 001 (or any other system). Once you have your songs mixed, open them up as two track files into your system. Song #1 will be on tracks 1 & 2, song #2 will be on tracks 3 & 4, etc. You can quickly compare their levels that way, make adjustments, and record a new master file (mix to disk) of any that you changed. Once you get more familiar with your system you will find other tricks to help you get more songs in at once. One obvious one would be to string the songs back to back on the same two tracks until you’ve recreated the entire CD you want to burn. You can then adjust their levels and then mix them one at a time or mix the entire length of the CD as one file (be careful, because you will not be able to separate them later in Toast).
As I said, this can all be considered part of mastering. You should also develop the skill to make consistent mixes so this kind of level anomaly decreases in severity and frequency among the work you do. The general rule of thumb in digital is to print mixes at very high levels, using compression, normalization, and any other available tools you deem appropriate. They all help with this sort of thing, but they can all be used inappropriately and can degrade the sonic quality of the music as well so be very careful. Most mastering engineers report that they like to get music that is relatively uncompressed because it gives them the most leeway to do what they need in the final stages. You should make decisions based on what you ultimately plan to do with the material.