Anatomy of an Overpriced Cable
Some years ago while innocently drooling over equipment at my favorite audio store, I was bitten by a rabid marketer. At least, that's how I explain it now. I felt no pain at the time, but several minutes later I left the store carrying a pair of interconnect cables with a pricetag north of $100. Interconnects, yeah. You know, the cables you use to connect your CD player to your pre-amp.
Now, those of you who have used reason, a knowledge of physics, or your own native skepticism to avoid the rabid marketers and their electrical mythologies are probably already snickering. On the other hand, some of you may have spent as much or far more for your cables, and may feel that the sonic contributions of these handsome conductors exceeds even that of the bubinga chips carefully arranged atop your amplifier's aluminum housing. Regardless of your personal beliefs, here's an important question:
What's in those little boxes?
Well, the makers of this particular brand of cable describe the hidden whatever-it-is as a "network". Aha! So there must be a bunch of interconnected things in that little box. That's probably why it's relatively large.
They certainly don't look like they were built to be opened - they're obviously made from two separate pieces of plastic, but there's no apparent way to convince them to come apart without breaking them. And I wouldn't want to do that because...I spent so much money on them. A dilemma.
Well, years passed, and eventually I got around to replacing these cables with something more conventional. Somehow, the music on my stereo still sounds great, but I could well be a tin-eared ignoramus, so this means little. Now that these networks are no longer contributing to the musicality of my music, it seems like it's time to open them up and find out what's really inside. An Xacto knife and a small screwdriver did the trick.
And there it is: the white conductor has been cut and soldered to a black component of some kind, the other conductor has had a piece of tape put around it to hold down the loose white plastic strands that add tensile strength to the cable, and then the whole assembly has been zip-tied to a plastic piece which was taped to the inside of the little box.
The black component has writing on its jacket, which says "Renco RL-1284". This turns out to be a power line choke. In other words, an inductor. Here's a datasheet for it (warning: PDF). The particular one on this cable appears to be a 15 µH model. It also seems to be about $2 in quantity one, judging from some quick web searching.
So no matter what your view is on the great audiophile cable debate, or on the virtues of sticking an inductor in the middle of an interconnect, one thing is clear: there's nothing inside that box that costs more than $2.
I'm also not sure that even a very charitable definition of "network" could apply to a passive component soldered in series with a wire.
There are some other interesting things about this cable, too. Under the insulation, it's shielded with foil. The shielding is cut away for a little less than an inch to mount the component on the conductor. Not a big deal, probably, but for this much money wouldn't you think they'd make sure the shielding was continuous? It's also not coaxial cable, which is unusual for interconnects.