Operation
EQ Principles
First cut, then boost: The hearing system is more used to energy reductions in a frequency range, thus boosts attract more attention. That is, a 6 dB boost is perceived to be similar in amount to a 9 dB cut. Therefore when wishing to emphasize one frequency, it is typi- cally better first to consider a reduction in others. The result will bring more transparency and clarity as well as reduce possible unwanted coloration of the signal.
Boost harmonics: Harmonic enhancement is one of the foremost tech- niques for increasing the clarity and definition of an instrument. One overtone area for vocals is around 5 kHz and accentuates presence.
Note that each instrument will have at least two frequencies where EQ can achieve a greater clarity or brilliance.
Cutting fundamental levels: Cutting fundamental frequencies pro- vides for a perceived increase in harmonics and is therefore an effec- tive alternative to boosting harmonic levels. This is a common practice in Rock/Pop productions that can be effective in all musical recording genre.
Boosting fundamental levels: Inexperienced audio engineers will often first try to make corrections by boosting fundamentals, some- thing which in fact should be the last thing one considers. Boosting fundamentals typically lowers clarity and produces a muddy sound. If two instruments are playing the same part and thereby produce the same fundamental, raising these levels will lead to a decrease in the sonic difference between them, (i.e., will make the two instruments sound more alike and lower their intelligibility in the mix). This is also true when two instruments play similar parts in the same key.
Exception: When an instrument sounds thin or small, boosting the fundamental can help. Or perhaps a microphone was poorly placed or the harmonics had been raised excessively through EQ. Finally, increasing fundamental levels can also play a constructive role when instruments play alone or as soloists with others in the background.
16 | RackPack: Vox Ranger |
