There are major differences between commercial recording sessions and rock recording sessions.
In general, a commercial recording environment will be more structured. The goal in these situations is to record the client's music in an efficient, professional manner to achieve a clean, reliable production. The musicians and singers called upon in these situations are professional and versed in many styles of music, as are the producers and sound engineers. These sessions may account for a portion of a larger budget, and therefore scheduling and performance are emphasized. The environment doesn't lend itself to creativity and idea exchange. The people involved are expected to know their jobs, do their jobs and move on to the next job.
A rock recording session, on the other hand, is typically a much less structured affair. While a good manager and music producer will have the rock band rehearsed, scheduled, planned and ready (to save money) departures from this environment are common. Bands may wish to explore new ideas and directions as they emerge. This may lead to experimental recordings and "jam sessions," during which the band members try new arrangements, songs or lyrics. Sound engineers and music producers can play a large role in this mix, keeping up with the evolving ideas, capturing the good ones and discarding the bad ones, trying to keep the project on track without stymieing the creative energy. This technique doesn't only apply to rock bands, but country, hip-hop and rap artists as well.
The mixing process also may vary between commercial and rock recording sessions. At a commercial mixing session, the client or end-user of the recording may have a representative there to oversee the final sound. This, for example, might be an advertising executive or director. At a rock mixing session, the collaboration might include the band members, producer and record company representative. All will have varying degrees of input on the final mix based on their working agreements. But the emphasis will be on creativity and marketability of the music.
New software programs and easy Internet access are changing the way recording sessions are being done. Find out how online recording sessions work.