Changes to older system

First and most obvious choice is cabling, but what?

Actually, wires are the last thing I’d worry about here, but a lot has changed/improved over the past 30 years so I think a complete overhaul is in order. Start by identifying which speakers really grab you and then I’d recommend finding an integrated amp that has enough power to drive the speakers and is a good sonic match for them. For a source I’d recommend an Innuos Zen Mk 3 that you can load all your CDs into and have all your music at your fingertips, and it’s also an excellent streamer so you can explore worlds of new music — much of it in high res. Only then would I address the cables. Anyway, that would be my plan of attack FWIW, and best of luck

Actually, wires are the last thing I’d worry about

Depends on if new equipment is desired. I used to take an equipment first approach, now to the point of tuning my equipment with cables. Once a non-believer in cables to sound, it's now one of the main things I've found to make a huge difference. Sometimes to the extent it sounds like I've swapped out the component..

I would try placing the speakers right against the wall to take advantage of boundary reinforcement. That is what my Snell Type A's use. Contrary to what above poster rickysnit claims I find no sonic differences between any cables. Including power cords. I have that NAD 1600 preamp in my collection. It and the 2200 amp are excellent! Yes, you can buy new gear for thousands of $$$$ more but sonic differences would be minimal! I'd consider getting a transport and DAC for what I assume is a nice CD collection. Regarding B&W speakers: they have been known for a long time as having particularly bright treble. Placed against the wall and firing straight out will help alleviate this.

I have experience with an NAD 3150, and some Snell EII speakers. It was a very pleasing combo, and I liked it so much that rather than sell it I gave it to close friends. They play the system daily with their LPs and CDs, and I have somewhat regular visiting privileges.

The Snells, in spite the back firing tweeter, are placed in corners for the sake of furniture layout and owners preference. I think we used brown zip cord for speaker cables. Decent bass, not bright, and sweet vocals. It’s surprisingly good. 🥃

I suppose you play “House” music on that system @zimmer266 ?
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