Sound II Reading

Masking is one of the most important psycho acoustic principles to consider when mixing.

This effect of one particular sound effectively blanking out another sound can occur in two distinct ways: frequency and temporal.

Frequency masking  

the phenomenon of louder signals blocking out quieter signals of similar frequencies. This is why it is vital to use equalization to create space within the mix, as two instruments that sound beautiful in isolation may compete for the same frequency range within the ear – and so need to be equalized to work together.

Temporal masking 

the effect whereby a loud sound (of any frequency) restricts how we hear a quieter sound that is played at a similar (but not simultaneous) time. Both pre- and post-masking can take place if the time difference between the signals is short enough, so a quiet sound can actually be masked by a louder sound that comes after it.