How much compression does the compressor knob apply and what does the more button do?

In normal mode (without the more button pressed in) compression is applied with a ratio of 2:1. When the More button switched in, the compression ratio is switched from 2:1 to 4:1.

In normal mode and more mode. as the Compress dial is turned clockwise, the threshold is reduced and the make-up gain increased. As More mode
utilises a higher ratio (hence more compression), there is more make-gain applied to compensate.

The attack and release times for both modes are 1.2 ms and 28 ms respectively.