With all these possibilities, you might wonder where to start. Although there really isn't any single “correct” order for the mastering process, most tracks benefit from a commonly preferred order: Equalization, Compression, Excitening, Widening, Reverbation and Loudness Maximization.
Only a dedicated EDM mastering engineer can achieve what record labels and artists find appropriate for the particular track.
At this mastering stage, it is assumed that equalization has been done properly for each track during the mixdown. Therefore the goal is to shape the track to an excellent “tonal balance.”
This might mean that the mastering engineer may improve the tonal balance considerably using equalization for both broad correction of only 1-2dB while cutting nasty frequencies aggressively.
After equalization, something easier said than done, the engineer will typically use dynamic processors ('compressors') to improve the tonal balance further. In the case of Electronic Dance Music (EDM), listeners expect both deep basses, transient rich drums and arpeggios and exceptionally lush synth pads as well as abrupt transitions!
This is difficult to achieve, because most hits have a gluey tight consistent characteristic. Careful dynamics processing can smear the transients and add glue on some sections, while expanding the dynamic range of other sections.
When the master is tonally balanced and has an impressive stereo image, exciters and enhancers can be used to add sparkle and increase the perceived loudness and energy.
There are many design strategies behind exciters, from tube and triode distortion to short delays and tape machines. A harmonic exciter adds psycho-acoustic power and punch by adding a combination of odd or even harmonics.
When tubes saturate, they exhibit a harmonic distortion that artists term warm and musical with a presence and sparkle. Boosting high frequencies with a regular equalizer will not achieve this pleasing effect, but passive tube equalizers can both boost existing and add harmonics in a similarly flattering way as an exciter.
Tape saturation can also provide a similar, but more aggressive excitation effect, adding more odd than even harmonics. When applied by an experienced mastering engineer, odd and even harmonics are added while the natural characteristics are preserved.
Many tonally balanced mixes, also those comprised of professionally panned and processed tracks, still sound a bit small and boxy. So, what is missing? To maximize the emotional impact and experience, the stereo image can be manipulated further. This frequently means that the stereo image is widened so that some tracks seem to jump out of the speakers, for that famous 'around-your-head' sound.
It is very difficult to achieve both a wide stereo image and density. Over application of widening will make the master sound thin and diffuse. Only very skillful mid/side stereo imaging, separating bass and mid frequencies, can prevent phase and mono compatibility problems.
A good mixdown has a great sense of space achieved using reverb on individual tracks. What the EDM mastering engineer needs to do is to add a little extra reverb that smooth over the imperfections, adds a bit of rumble and even improves the bass. This can also be achieved using delays, flangers, phasers and choruses.
In most cases, mastering reverb can unify several tracks. It is also not rare, that the mixdown has been cut so short so that the mastering engineer has to add a fade out reverb.
The main consideration of loudness maximization is to make the track sound louder than it actually is. A louder master is perceived as having an enhanced the presence and impact. While the latest advances strive for transparency, soft and “smeary” analog limiters can also be deliberately chosen to achieve a vintage sound. The vintage feeling can also be achieved by lowering the level of the main frequency of the kick drum, which can make the track bounce more.