Originally Posted by theborg7of7
Thanks for your reply.
I'm a bit confused about your story. You and your buddy didn't notice that you had taken his expensive power cord? You didn't notice that (I'm assuming that you have a 15 amp IEC connection on the device) you had a different power cord on your oscilloscope when you plugged it in at work? Did the stock power cord from your device look identical to the high-end power cord? If so, what brand was it? I'm not aware of any higher-end power cords that look like a black 16 amp Beldin. Your buddy invited friends to rave about his new power cord and yet didn't notice, nor did his friends, that it wasn't even there? He didn't mention to them, 'Hey, here's the cord I told you about,' at any time during their visit?
The cord was indeed very close to a standard power cord of the very heavy-duty variety with similar (grey, in this case) outer sheath, but it was larger in diameter. This was a long time ago and I do not remember the brand; newer power cables have evolved, natch. I realized I didn't have an extra power cord on hand after I got there, and he had lost (misplaced, anyway) his amp's original cord, so I had borrowed it so we could compare a "regular" cord to his "supercord". I measured the supercord and a few regular cords while we were swapping things around to see if we could hear and/or measure any differences at the amp's output. He was not handling the cables so the testing was blind to him; it was my bad for not srestoring the cord. Perhaps his for never looking behind the stand to make sure I got it back, but...
What followed was simply bad timing and poor follow-up on my part. I had borrrowed the equipment from work and had to get it back that (Sunday) night for use the next morning. It got late, and I threw all the power cords and other cables into a box when we were done and did not notice I still had his supercord. The power cords went into a "pool" box at work -- I just dumped my box into the pool. It was a couple of weeks later I noticed his supercord on my 'scope and returned it to him, a bit embarrassed. As was he when he found out he and his friends had been finding differences where none existed, at least not due to the power cable.
As I said, in addition to decades as an EE putting me firmly into the "science" camp, this episode predisposed me against power cables making a difference. This was back in the 80's when cable hype was rampant and the technical claims were really outlandish (today's claims seem couched in more scientific terms; does not mean they are more or less outlandish, just that at least some effort went into writing them down). I have not tried swapping power cords in my present system, and have no plans to, as I think there are many other and more critical factors for sound quality, plus my general skepticism about the claims.
I am a little wary of shooting down what someone hears as I have been through cases when the ears did win in the end, but there has always been a scientific reason that matched known theory. I have been through far more cases when either (a) the ears were wrong when put to the test, or (b) we could easily measure something the ears could not hear (e.g. showing a graph with a large roll-off at HF for standard cable was once done by a manufacturer; the curve showed a big difference to their cable, when in fact the vertical axis was in 0.01 dB steps or something like that, and the horizontal in MHz or similar -- no way it mattered in the real world!) Claiming I can bias a cable to eliminate sub-uV noise traps and such may be true, but you'd be unlikely to ever hear something like that (e.g. a 16-bit DAC with 1 Vpp full-scale output has a 15 uV lsb step; we can resolve a bit below an lsb for steady-state signals, but less than 1/10th? I think not...)