System bottleneck?

Tablejocky No doubt!

Agree with most above. If streaming by bluetooth, correct that immediately. Especially if this is your primary source.

Secondly, new turntable. You didn't mention your phono preamp, maybe that too.

Can you elaborate please? Are you streaming from the internet to your phone and then bluetooth to your Marantz? Do you have a server on a home ethernet/wifi network?

Ok. What I am doing is streaming internet to phone and then using Airplay 2 to connect to marantz. Another  thing I do is play mp3 files from a flash drive connected to marantz. I also play hd radio through marantz. I do not use a computer or have a server on my home network. I could use my laptop in that way but when I did I did not think it sounded as good as streaming through my phone. My marantz recognizes my home network but I only use it in the sense that my phone communicates with the marantz to play my playlists which are not downloaded to my phone. Does that make sense to anyone because I’m not sure it does to me. 

russ69 the signature se’s have pretty good bass response.

Actually, I'd recommend a set of woofer towers (or vertical sub array). You would have a near Infinity type RS1B at that point. Very powerful, and miles of depth.