Marantz PM8005 as preamp

Interesting discovery:

I’ve been playing with all my gear in a new house and listening room. Trying to find best sound. I have a pair of JBL studio 530’s, Heco Aurora 300’s , and my best is Yamaha NS-200MA’s. 
I have a pioneer elite A-35R which is really good for what it is, a Rotel RC-995 with a RB-930AX and RB-850, and also a marantz PM-8005. 
the Rotel pre/power sounds really good, but I connected my marantz pm8005 as a preamp only to the 930AX, and it is better than the 995. 
I believe the amp section of the 8005 holds back the excellent preamp in that unit. Allconnected to the yamaha NS-200MA’sproperly setup in my room sounds absolutely fantastic. Anyway, I’m stoked.