My CD has to sound louder than any other disc ever made. Okay?
All kidding aside, this is a concern of record labels whose product is headed for radio play. We've also done some sampler discs, and each artist on a sampler wants their sound to stack up well against the competition. Everyone is looking for an edge, and sheer volume is an obvious way to get that edge. Years ago it was shown that if you play the same piece of music twice for listeners, one time just a bit (1/2 to 3 dB) louder, most folks will prefer the louder playback. Stereo loudspeaker salesmen have used this trick for years to sell "house" speakers that carry the highest profit margin.
If you want maximum level, there is one good reason to go for it at the mastering stage. Like it or not, radio stations will jam your music through their own limiters prior to being transmitted over the airwaves. The sonic quality of these processors is usually not perfect, to say the least. The processors in a good mastering facility will produce high levels and better maintain the sound quality that you have worked so hard to create. We keep highly modified multi-band compressors on hand just for this purpose. The limiters at the radio station will still be in the signal path, but they won't affect the sound as much.
What are the other considerations? If you master an album super-hot, for airplay only, all the tracks will sound punchy, but you run the risk that people at home will experience listening fatigue after 15 to 30 minutes. Music buffs generally don't enjoy hot sound for more than a little while, even if they like the material itself.
Looking at this problem from a music industry perspective, record labels are getting locked into a no-win contest to be 1/2 dB louder than the next guy. What gets sacrificed is clarity. You can always push the level up a bit, but the live feel and sense of air will suffer. A good home listening system can reproduce over 90dB of dynamic range. This is wasted when the music is crammed into the top 10 dB.
The solution? It’s usually possible to settle on a fairly hot compromise level that keeps everyone happy. For those who want to push a particular track very hard, one possible scenario is to release promotional EP's or singles, equalized and compressed for airplay. The record store version can then be mastered for a hi-fi home environment.
Technical tip if radio play is important to your release... be sure to check your mixes in mono as well as stereo. If there are mono compatibility problems, large listening areas may receive a signal that is radically different from the sound you hear in stereo.
To summarize, if you want your whole album as loud as possible, we'll work to make it that way. You just need to be aware of the tradeoffs.