Hi - newby to this and first post, I have an old Denon AVR 1700 that has served me well for a number of years and recently brough a passive sub woofer and a marantz mm7025 power amplifer to drive it, as this power amp does not come with volume levels on the front panel how do I crank it up for home theatre and then down again for music? can i do this independently from the AVR1700?