If your mixes are compromised or not mixed well, stem mastering maybe a better solution to the conventional mastering process. Although stem mastering is not offered by many mastering engineers, this service is relatively new and can be slightly more costly.

Relative to the conventional mastering process, your mastering engineer will normally request you to provide him a stereo mix of your song(s). However, if you are going ahead with stem mastering for one of your songs, then you will need to provide your mix in separate groups such as drums, bass/synth guitar, vocals, guitars or keyboards. Stem mastering can require up to 4-5 groups of the above mentioned groups depending on the scale of problems identified by your mastering engineer.

Stem mastering corrects relationship errors between instruments and vocals which includes volume and panning relationships.

For example, if the mastering engineer feels that the lead vocal are too buried in the mix, he may have the option of boosting the levels of the vocals. On another problematic scenario, the mastering engineer may have the need to alter the relationship between the kick and the bass guitar/synth bass. Perhaps there is current problem in the mix where the bass guitar is too prominent and the kick is too faint. As a result, there is a need for the mastering engineer to fix this relationship. In another problematic scenario, the guitars or keyboards are panned too centered thus narrowing the width of the mix. Through stem mastering, the mastering engineer has the ability to fix this problem via adjusting the pan on the guitars/keyboards. Through stem mastering, the mastering engineer gets to dip is feet just a little in the mixing domain.

Below is a list of what Stem Mastering cannot fix:

1. EQ error for instrument(s) or vocal(s) – Though is an optional fix on the discretion of the mastering engineer.
2. Over-application of effects on a particular instrument – Cannot be reversed
3. Over-compression – Cannot be reversed

Below is a list of what Stem Mastering can fix:

1. Volume relationship errors within instrument groups.
2. Pan relationship errors within instrument groups.

While some mastering engineers offer stem mastering, other few mastering engineers offer consultation and advice to your mixes. This applies to a select few mastering engineers who understand the integrity of mixing and simply care about their client’s project thus making an additional effort to collaborate with you in order to achieve better mastering results. With good communication, a mastering engineer can translate vital moves where you can personally make adjustments to your own mixes so as to enhance favorable mastering results to your song(s).

But above it all, having your song mixed professionally is a far better superior solution to stem mastering as more than half battle would have been won. With stem mastering, it can only fix up to 25% of the problems relative to what a great mixing job can achieve.