Yep, I've done it (with my Focus FS888), and it definitely has an effect, but for my specific situation, I actually like it without the jumper. In my setup, I use different wires for highs and lows (Audience Au24 for the highs, Acoustic Zen Hologram II's for the lows). IMHO, the Au24 is nearly unbeatable for highs/mids, but when using a high-powered amp and 4ohm speakers, the Au24 does not have the bass performance that I like. Also IMHO, the AZ Hologram is fantastic at bass. Some people say that using different wires creates problems with integrating the highs/lows, but I have not found this to be the case...perhaps because both Audience and AZ use the same OHNO copper?
Anyways, adding the jumper to the negative speaker terminal improved the things you mentioned...larger soundstage, better air/spacial cues, etc. However, I did lose the bass performance of the AZ cable when I did this. I haven't yet tried using the same wire top and bottom with this tweak, but I wouldn't be surprised if it made differences...
Anyways, adding the jumper to the negative speaker terminal improved the things you mentioned...larger soundstage, better air/spacial cues, etc. However, I did lose the bass performance of the AZ cable when I did this. I haven't yet tried using the same wire top and bottom with this tweak, but I wouldn't be surprised if it made differences...