Optimize Stereo Experience - NYC Studio


Hey, happy new year to all - new to this board but been lurking for a couple of years now.

Needed some help with this 2.1 stereo system I've assembled in my small NYC studio apartment: NAD T 758 + pair of KEF R900. I use Amazon HD and Spotify to stream the music. Below pic shows that my room layout doesn't allow for placing the two speakers in a straight line (have tried all other room configurations, unfortunately this cannot change). I have so far 'corrected' this via DIRAC and sounds significantly better with it. Had the following few questions in case anyone case help.

- Any further additions to the system hardware to make the sound improve significantly (amps, wires, speakers etc)

- Would a center channel speaker make sense. I mostly listen to music but sometimes do watch TV/Music too. I have a feeling the dialogue can be improved if I add a center channel.

- While I tried to test A/B Spotify vs Amazon HD and couldn't hear a very drastic difference, would love to have people's opinion here. I would definitely prefer Amazon HD over Spotify, but the crappy UI of the Amazon in BlueOs (NAD) makes life much easier when browsing for new music on Spotify.

- While I can't change where I live, any other tips / suggestions re speaker placement?

https://ibb.co/dmRD1Ph
128x128kmalhotra
Thanks - turntable for audio quality from vinyl? I'm low on space but let me look into it. Definitely a much richer listening experience overall, but trying to figure out how much it'll add to sound quality.

Will pull speakers away and re-calibrate DIRAC. 
Thanks - re subwoofer, I actually have to tune down the bass on these speakers given the condo situation (neighbors + thin walls). I found the bass on these R900s plenty deep + tight for me (love bass btw)
Hey.

First, consider Roon.  It has Tidal but not Amazon music support.

Next, you really need room acoustics!! Do that first.  When you have gotten some panels, rerun your Dirac calibration.

https://www.atsacoustics.com/
https://www.gikacoustics.com/