I was using two pairs for a BC Acoustique ACT 4 loudspeaker that required Bi Wiiring so each speaker needed one pair of these marvelous Lloyd Walker gizmos. These have probably less than 20 hours of use on them.As for what it does to the sound, well it is pretty amazing .It increases the mid range in that it feels as though you have more of it. I like mid range so that makes sense to me. Also another trick up its sleeve is how the soundstage moves a few inches closer while evreything gets a tad bit larger . In a sense ,you will have more boogey factor in your music and everything sounds sort of like a good turntable has been added to the mix. Please contact me via my e mail since I will not get any notifications from Audiogon. Use firstname.lastname@example.org . The price includes shipping .Buyer will pay paypal fees of 3%. The reason for selling is because I have sold the speakers and no longer need the two pairs.The have been in my system for 4 months ,not used for the past 1.5 months since the speakers have been sold.I will only pay shipping in U.S.