Neither your Denon nor your ADA-1000 will give you a "black background". The 1250 is better in this regard than the 1000 and the 1500 better still. I've been trying to understand what noise level gives diminishing returns. When I get my 1000 and 1500, I'll be able to assess this better.

A-LFR/1000-8 & 2/500v4x2
Air Force, Freedom
had v2