I own a Node and have not auditioned the C-658. Anything that can improve your room acoustics is a plus, I think the upgrade to dirac (and a few room treatments) would be HUGE.
We are an Nad dealer the c 658 is the same streamer as the node.
the c658 is a very nice unit however if you are looking at a radically Beter
we would suggest a432evo standard a Roon core and Endpoint $3500.
Dave and troy
Audio Intellect NJ
US importers 432 evo music servers
Personally, I would stick with the separate components, instead of going with the all-in-one NAD.
It will allow you to improve your system, one piece at a time, especially if you want a better dac than is provided in an integrated amp.
As far as Dirac goes, I would suggest that room treatment is always the better option. instead of monkeying with the sound.
@audiotroy Good to hear…at least the C658 streamer isn’t worse than the Node! Do you have any idea how the DAC in a C658 compares to a SMSL M400? Do you know what kind of power supply is in the C658?
I would look at the Evo when I get the funds to make a significant upgrade.
@tony1954 Yes there is a benefit in upgrading single pieces. But there might also be future all-in-one unit upgrades too. Components from different manufacturers don’t seem to work together seamlessly. Plus there’s too many wires.
On my room, I’ve added area rugs, etc., but it’s almost all glass windows and doors. 5 sets of glass patio doors, and 7 glass windows/doors up to 8ft by 8ft floor to ceiling. Whether DIRAC can improve that situation I can’t say.
OP, it seems like you have some good questions. I found the C658 thread on StereoNet to be the most informative and helpful. You may have to register as a new user since there’s a page limit if not logged in. If wanting to stay with the all-in-one route, as well as with NAD, there’s also the newly released M66 (but at more than 2X the cost). DIRAC helped my situation when I didn’t have room treatments, but I slowly stopped using the more I added diffusion and absorption. Like all things in this hobby, it depends on your situation and preferences, but it does seem like DIRAC could have a positive impact given your situation - especially if you purchase the full DIRAC Live version.