Looks like no loudness control on the PM8005. You do have a midrange control, you could play with that to see if it helps. On paper Marantz says the 8005 has a "robust" power supply. The problem is there though or you wouldn't have posted. If the Focal are biampable you do have preamp outputs to add a power amp. You also have two sets of speaker terminals, you could try bi-wiring to see if it helps at all.

I did see mention of a "direct" mode which I believe bypasses the tone controls etc. You may want to make sure this is off at low volume as the tone controls will add some richness at lower volume.