[GeorgeAb]

I just replaced my speaker terminals the large chunks of brass (approximately 70% copper and 30% zinc) and steel nuts securing them out with copper small terminals getting the brass out of the signal chain. It was a fairly easy, not expensive and fun DIY. 
     
With most speakers that utilize an internal crossover there are one set of speaker terminals. With an external crossover there is a minimum of two. The VR-60 utilizes seven sets of terminals for each speaker which is a total of 1.7 pounds of brass, so a little over 8 oz of zinc in the signal path. Replacing with copper WBT or vampire copper connectors would get expensive and they are large hunks of metal. 

Really impressed with the Electra Cable Tube Connectors sold by GR Research. Just gold plated copper, tube surrounds a large length of wire and wires are essentially tip to tip. Excellent mechanical connection before soldering, massive amount of surface area making contact with wire and connector, reasonably priced, and fairly straightforward DIY.

Does it make a difference in how it sounds? In my room with my setup going through multiple sets of brass terminals, yes it does. That said, for some perspective. I recently replaced a set of OCOS speaker cables which were a highly regarded sonically in the late 90’s, early aughts with Acoustic Zen Satori Shotgun cables designed by Robert Lee formally of Harmonic Tech. A well regarded modern speaker cable. When I made this change, I was kicking myself for not doing this years ago . I do not feel this way with the getting the brass out tweak. I believe there is an improvement, but I am not regretting doing it years ago. Is this all in my head? Maybe, but I am getting excellent sound and IMO it is due to addressing these types of details.

[ric]

No, I think the most important thing (your ears) are telling you all you need to know. But that doesn't mean if you don't obviously hear it that it isn't an improvement. Take vibration control, if you do it to one piece of equipment, you may not hear a difference, it depends on two things, the sensitivity of your equipment and the sensitivity of your ears.
     Ric Schultz of High Fidelity, has some YT videos, one in which he suggests replacing the (magnetic, steel) screws that hold your speaker to the frame with brass screws. I tried it with some Herbie's anti vibration material, and to my ears was a big improvement--others may not hear it as much. Cheap tweek and well worth it IMO.
   I am also a huge fan of Iso Acoustics products. They offer a return policy and I use them under every piece of equipment. My experience is vibration control will improve to varying degrees, tighter bass, improved imaging, improved clarity and more of a rightness to the sound, meaning it sounds more realistic.
   Oh, and a while back there was a listing on Craigslist for some older MIT MH750 speaker cable for $120! I tried them thinking they would not outperform the Morrow cables I had, but to my ears the MIT just sound more natural and realistic, so I sold the Morrows and eventually moved up to the MIT Magnum M1's, so, it may be system synergy, but that's what my ears told me.
   I use many other tweeks, but space is limited, enjoy!

[G E]

Great posts !

I no longer have pre-conceived notions of what does and does not improve sound.

Power cables the most recent example. They don’t all make a big improvement but some do and it’s astounding.

I had some high end Morrow cables. Their entry and midrange were better than the Blue Jeans stuff (easily heard) and I moved up to their Elite Grand reference in some positions. Better, but the midrange Black Cat 32xx series easily bested them. And Black Cat Graceline Setsuna Level 2 blew me away !  Wow!

Why wire makes a difference I don’t know. But easily heard with the right stuff.

[Mike B.]

I think your efforts were good ones. Especially reducing the mass of connectors. Every connection is a resistor.