Lately I have been using Electra Tube Connectors for speakers. I tried them because they had two factors I wanted, pure copper and no threads. I couldn't afford the more expensive brands that have those qualities, and I've been very happy with how these work and sound. To me they are the ultimate low mass speaker connection, just simple tapered copper tubes that slide together with tight fit, very large contact area. I still use my 5ga speaker cables with them for now, but I'd like to experiment with lower mass silver DIY SCs, if I can keep the same kinda bass control.