ADVICE PLEASE

On my lower end system I made my own speaker cable with 12 AWG pure copper low oxygen "lamp cord' as @millercarbon calls it. Put decent banana plugs on it and I'm happy with it. Can be done with little skill and no tools. Its a step up from the 18 awg stuff from Walmart anyway.

I think for immediate, low complexity, low expense enjoyment with good SQ, CDs and a decent CD player are very hard to beat. And there is a nearly endless supply of cheap used CDs out there. That is where I would start.

Then I'd look into ripping them. But that gets complicated really fast unless you drop some cash for an all-in-one ripping, storing, playing solution like the Blue Sound Vault 2i. About $1200. Many here will tell you that its DAC is no good though.

I currently use an old iMac with iTunes (free), XLD ripping software app (free), a $30 USB cable and a used Schiit Modi 2 Uber ($110). I'm listening to Steely Dan - Two Against Nature ripped CD right now through this set up and it sounds great to me.

Don't spend any money on cables right now.

I'd focus on speaker placement, and room acoustics. See GIK Acousutics website.

Find the manual to your speakers  and follow the instructions carefully about ideal placement.

Listen for the instruments being able to transition smoothly from L to R without gaps. Leave enough space to the outside of the speakers so you don't have early reflections. Throw carpets/throw rugs around the floor between and behind them and listen again.


That's where you should start.

If you want to spend money on surge protection, the $180 Furman is the best value and most reliable I know of:
https://amzn.to/2PG40Fi

I agree with erik, that Furman is an excellent unit and is very hard to beat for the money. I'll so far as to say it's better than many power conditioners in the $1000 to $2000 range.

Sell the receiver and get a better amp that suits your needs. Do you really need or want a monster 7.1 channel amp? What are your sources?