Spade vs bare wire

Funny, if you look at many threads here with same question from 10 or so years ago, bananas were the worst choice. I’m sure quality of connectors has improved quite a bit. 

Keep in mind that if 6-nines copper is important to you, then bare copper wire is continually oxidizing, and copper oxide is a semi-conductor (a diode). Guitar effects manufacturers use diodes to create distortion boxes. Silver oxide is a conductor, so there’s no problem with silver.

I love the low-mass architecture and the metallurgy of the ETI / KLE / Eichman connectors and we selected ETI for our cables. There’s a bit of confusion over the 3 names, and if you’re interested in the genealogy, you can find it here: http://www.eti-research.com.au/the-original-bullet-plug/

ETI dispenses with the intermediate nickel layer found in many connectors which I refer to as audio jewelry - pretty stuff, but sonically lacking (you know who you are).

How much the metallurgy contributes to their sound is impossible to say, since I wasn’t privy to ETI’s prototyping sessions.

What I can say however, is that the connectors I’ve heard with an intermediate nickel layer have a characteristic distorted sound to them.

The ETIs are silver over copper, BTW.

Disclaimer: I have no commercial interest in ETI, but I do have an interest in building the best cables that we can deliver to our customers.

... Thom @ Galibier Design

Both silver and copper wire will oxidize if using bare wire you should tin the wire ends but do not allow the solder to penetrate the insulation as that will contaminate the tinning. 

There is a vast chemical difference between tarnished and a metal's oxide. In a normal room environment, metal tarnishes, so the validity of the oxide conductivity is specious.

Gas tight connections are best. Bare wire in a connector is a poor idea as it will tarnish. Gas tight connections can be effected with crimps, but require the proper tool, connector and wire. Soldered connections may sound a little different, but it is unlikely that the solder is the issue. There can be several dozens of soldered signal path connections in every device.

Worrying about solder when there are likely multiple crimped and soldered internal loudspeaker connections is silly.

A standard speaker connector with a well crimped/soldered ring or spade terminal cinched down with a nut driver makes an almost permanent connection. The two layer WBT are as good and don't require as much torque to keep tight.

https://hackaday.com/2017/02/09/good-in-a-pinch-the-physics-of-crimped-connections/

https://media.digikey.com/pdf/data%20sheets/molex%20pdfs/tbo%20quality%20crimp%20handbook.pdf

AND, AS ALWAYS, YMMV. Any advice not generated in your context is worth 0x0000000000000000000000000000000

This is not the vendor I've used in the past, but these low-mass BFA style banana plugs look like the ones I've used in the past:

https://www.moon-audio.com/bfa-gold-banana-plug.html?gclid=CjwKCAjw27jnBRBuEiwAdjQXDBxSG5U7-ovA8GR2-oQd-blBAuCC1zw1aYl8MB8JBK74ZJb094cC3xoC3HMQAvD_BwE

I typically clip off the crimp wing and solder them to the cable. They work perfectly. They have a large contact area, fit tightly and don't loosen over time.