I have the HK 3480 stereo receiver running a pair of Axiom M22ti and just found something really interesting and extraordinary, I was trying to hook up my new DVD player to the receiver and found two OEM jumpers(links) that connected from Preout to Main in, out of curiousity I'd replaced them with a pair of decent quality RCA interconnects, and man...that turned out to be a big surprised, I never thought it could make such a huge difference!! bass is punchier, soundstage is deeper and wider, image is more solid, definitely more detail and crispier in the upper end, both male and female vocal opened up quite a bit, I'm still in shock and can't believe what I'm hearing. I'd put the jumpers back in and everything just sound so...dull and lifeless, it seems like having a wet towel covering over my speakers!! Initially I thought I was tripping, and suspected it might of been my imagination, so I'd swapped the jumpers in and out for no less than 5 times, it never failed, the differences was extremely obvious, this is unbelievable...have you guys ever try to swap out these jumpers thingy? and what in the hell were they made out of?!?!?
I do not believe in $100/ft high end cable, never did and never will, but this finding is absolutely disturbing. couple minutes ago I take a closer look at the jumpers, whatever the hell is in between the two jacks inside the rubber boot seems fragile and weak, I use a swiss army knife to scrape one of the chrome color jack(ending) and the sucker chipped off, WTF???!! it appears to be some sort of cheap chrome coating or something, this sucks!!
Whichever genius came up with the idea of using these garbage to bridge the connections should be fired!! IMO the bridge or bypass should of been done internally, via the circuit board through a switch, or remotely, not through these jumper $hit!! I just did a search and found a bunch of people especially NAD C370/C372 owners on audioreview were suggesting the same thing, looks like we're not alone....
This sort of thing is common in speakers with bi-wire terminals. They generally come with a cheap metal jumper between the bass and treble terminals, which is removed to bi-wire. However, even if you don't bi-wire, this jumper should be replaced with speaker wire. I am not into "tweako" fixes and snake oil products, but I did this with my Wharfedale Diamond 8.4s and Radioshack speaker wire, and the difference was easily noticeable.