So the first choice would be to set the bright switch to 7 at 0 gain and let the low cutoff boost the frequencies. Then put the bottom switch to about 10 at 8 ou 11 ou 12 ou to increase the attack/kick/bass energy of the low frequencies respectively.
The 'clean/crunch' mode would be used to add a more 'clean' warm sound to the preamp.

When using the LE456 VST as a preamp with the 6add127376 ingereg