I currently have a Marantz SR5005 but had the 950 previously. I noticed the other day when sending a 4.0 signal to the SR5005 7.1 Analog inputs that my LFM-1 EX sub was not turning "On" meaning there wasn't a signal detected. I tried other sources without their own LF channel active and nothing. I called Outlaw and talked to someone (not Scott). I was told that "Most 7.1 inputs do NOT have Bass Management." My 950 had it via a toggle switch in the back. I could not find anything in the 990 manual but you might try a test to see if the 990 7.1 analog inputs DO have any Bass Management. The person on the phone said "It is expected that customers would do the Bass Management in the DVD/Blu-ray for the analog inputs." So my SR5005 does NOT have Bass Mgmt with the 7.1 analog inputs and I DO have to set my Oppo with speakers small to use it for a signal to my sub via the Oppo crossover from the other channels.