The values are in dB and the Crest Factor is as you probably know 20*LOG10( Vpeak / “Vrms over time”).
A 12 dB Crest factor is the same as 1/8th power average over time compared to the burst rms power in the beats of the music. This is what we have found to be the worst case scenario over time intervals greater than 2 minutes in the applications that we expect to see these amplifiers. This is also what we use for power ratings at Lab.gruppen since 2005. A 16 dB Crest factor is generally accepted as a fullrange music value over time. This is the Crest factor in the burst tests used by ASC and Crown and in the burst tests in CAF (Common Amplifier Format). And the difference is that the power average is now
These values are set by us as we expect them to be for the different types of bands. They are used to calculate the expected losses (BTU) and current draw from the mains. They can be edited in the preference view by those that feel that they need to be higher/lower.