CD collection and Klipsch KG4

[LTRDavid]

Greetings,

I would like to ask for recommendations on what to get to best take advantage of my Klipsch speakers. All my funds went into the speakers back in 1985 and I scrimped on the electronics at the time. Now I would like upgrade - but reading the reviews online have confused me, because I have seen everything recommended. Here are some excerpts;

"Try the KG4 with a sweet low-powered tube amp, or a well-built smooth solid-state piece and see what you think then..." OK, so I tried the KG4 with a smooth tube piece (the wonderful Jolida Model 102B) and with a nice solid-state integrated (the reviewed Musical Fidelity A3.2), and you know what? I loved it!

Best to mate them with low end heavy components like the mid 80's NAD stuff. e.g. NAD 2200.

Yamaha M-50 main-amp and C-50 pre-amp the whole time and have been the envy of all my friends.

I POWER THEM WITH A DENON 80WATT PER CHANEL INT. AMP THE SOUND IS VERY REALISTIC

Also, I have a questions about this comment:

If you own a valve amp you need to give these a try. Rewiring with solid core copper [eg Axon 2 or 4] also improves smoothness of sound and ALWAYS use solid core speaker cable.

What's a valve amp? What is this "rewiring with solid core copper" and "always using solid core speaker cable" about?

I should note, I do have a Technics SL-MC7 CD Changer that I bought about 8(?) yrs ago, IIRC. It has an optical output, if that means anything. I do not have a problem keeping it as it works fine, especially if keeping it in service would allow more funds to invest in the other component(s).

Thank you very much.

BTW, here's a pic of my current setup.