Need tips to better my sound



I’m not computer savvy and enjoy the convenience of streaming.
Right now my router goes to my smart TV by ethernet cable. I stream Spotify app on TV through an optical cable to my dac (old parasound zdac) to yamaha integrated(a-s500) to Revel tower speakers.
Would the best Improvement be to get a dedicated streamer such as a blue sound? I heard blue sound doesn’t work with Spotify but maybe I could get Tidal? I have music stored on an external hard drive, but my computer is slow, old and crappy. I enjoy streaming and seeing my music choices on my TV screen. Do I need a computer to utilize a dedicated streamer? I don’t know how to go about improving this budget (ghetto) set up that I’ve got. The only brick-and-mortar store around me either wants to sell me tons of crap  I can’t afford, or Best Buy tells me "sonos".
suggestions? directions? thanks.
128x128labguy
Almost always the best upgrade is to make what you've got better before you go changing what you've got. In other words before buying another DAC get the most out of the one you have by upgrading its fuse, or power cord. Before upgrading computer upgrade the wires connecting it to your integrated. Before upgrading the integrated upgrade the fuse to Synergistic Orange, and add some ECT. The beauty of doing it this way, not only makes what you have now better but things like ECT are lifetime tweaks you keep and use on everything from now on. Same for things like BDR Cones. All these things, Cones, ECT, Orange Fuse, are $60-200 but will yield far more improvement than spending that same money on another streamer.
@labguy  Given where you are with your components, I recommend holding off on millercarbon's recommendations (for now).

Start with a streamer/DAC combo that allows you to run direct via Ethernet or WiFi from the router.

Not knowing your budget, I can't offer suggestions.
The blue sound node seems reasonably priced. Something like a Lumin would be pushing my budget. But I guess that all depends if I get a streamer with a DAC included that will better the parasound Z DAC, and if I need a computer to use a streamer. Mainly I just want to First address the weakest link in my system which I was guessing is using the smart TV's spotify app to stream. But maybe not? I'm pretty clueless. Thanks. 
Here's the best tip I have ever heard when someone asks how to get better sound from their system:

GET YOUR EARS CLEANED!!!

Hahahaha...;-)
The blue sound Node2i does support spotify if that’s what you want to use I use Tidal. You don't  need to use a computer with it and you can player your ripped music as long as it's  shared on your network. There are more than a dozen different streaming services on BluOS as well as internet radio.