Of course, the Mastering Engineer strives to control the sound to be processed as loud as possible. Es empfiehlt sich hier jedoch, den maximalen Pegel nicht bis auf die vollen 0 dB auszusteuern, sondern einen kleinen Head Room von -0,3 dB „Platz“ zu lassen.
Why only -0.3 dB?
The reason for this is possible overdriving that can be caused by the players (e.g., CD players) with their D / A converters. The built-in converters often produce slight changes in the sound (not necessarily audible, but measurable), which may result in distortion at a maximum level.
Also in the conversion to the MP3 format it comes to clipping in the case of a fully increased level. For this reason: Maximum modulation: -0.3dB or even less. This small loss of volume is virtually inaudible, but ultimately ensures that it does not come to unwanted clipping.