opaqueice Wrote: > > I don't have any particular opinion regarding whether power cords could > make an audible difference, apart from some mild skepticism arising from > what I know about electronics >
I'm with you on the skepticism. One of my previous roommates had a PS Audio Power Plant which converts AC into DC then rebuilds a clean AC signal - I thought he was completely crazy at the time (especially since it cost about $800). But back then I wasn't much into audio stuff and I regret not doing careful A/B listening with that Power Plant. opaqueice Wrote: > > (incidentally, I have the same skepticism about bi-wiring > speakers--assuming they're connected to the same thing on the amp end, > that is--and I did try it and didn't notice a difference). > It also depends on the speaker. I've heard that audiophiles just expect two sets of binding posts nowadays so speaker manufacturers supply them, but that doesn't mean the speakers are actually designed to take advantage of biwiring. I'm biwiring at the speaker and connecting them back to the same post on the amp (my AMP5 isn't designed for biwiring at the amp). Even still I definitely heard a difference. Even the more modest B&W 602 s3 surrounds got a lot better when biwired. opaqueice Wrote: > > So I'm asking just out of a desire to learn - what is the idea behind > replacing the power cord? What would the ideal power cord be like? > When you build one yourself, what are your goals? > I don't claim to understand much of it (any of it?). There are some simple things to consider though. The heaviest-duty component power cord I've seen consisted of three 14 AWG wires (the lower the AWG number, the fatter the cable). Usually cords will write something like "3x14AWG" along the length. Most cords I've seen are 3x16AWG. 16 gauge is a little puny. You'd feel a little crummy wiring your speakers with 16 AWG speaker wire. The homemade cables I made were 12AWG. I can't explain the benefits of fatter cables, but there's plenty written about that as it regards to speaker cable. There's also plain construction quality. Are the wire leads soldered to the connector plug with a cheap, poorly conducting solder? Or are they screwed down? What are the connection plates made out of? Are the wires cleaned before they're connected? I still don't know why that might make an audible difference, but if the AC has to traverse cruddy hot or cold welds, who knows? In the cables I made I added Walker SST to the wire connections. It's a silver paste contact enhancer. No matter how hard you screw down the wire leads, there will still be gaps in the physical connection. The idea of the paste is to fill in those gaps with a conductive material to aid the quality of the connection. Does it help? I dunno - I wasn't willing to spend the time to build a cord w/out the paste to find out. >From there things get a little fuzzier. The Chris VenHaus "recipe" I followed for my cables has an interesting approach to the ground wire - it's wrapped around the main 2-lead wire in the opposite direction (i.e. if you look down on the 2-lead wire and they're wrapped together in a clockwise fashion, wrap a third wire - the ground wire - counter-clockwise). Why? I dunno. He claims that yielded the best results in his testing. The 2-lead wire is shielded. That braided shield is then twisted into the ground wire for the wall plug end. The IEC component end doesn't interact with the braided shield (supposedly that draws the EM interference picked up by the shield out to ground in the wall instead of into the component). Then the analog cables (Flavor 2) add something even weirder - the main 2-lead wires are fed through a rubber air hose. The ground wire is then wrapped around that bulky hose in the same counter-rotation fashion. It occurs to me I should re-emphasize that I'm not a Chris VenHaus salesman or anything. I'm just a big fan of his cable design and supplies. Anyway, I can't explain the hows or whys of any of that. The shielded cables are supposed to keep noise out of the line and at the same prevent noise from leaking OUT of the cable. Maybe it's just the shielding and all the rest is gobbledygook (however the analog Flavor 2s are not shielded at all). All I can say is that it does work. I actually just had my sister and her boyfriend over tonight. He thought the power cord thing was totally crazy too. I sat him down and played that Telarc Sampler 1 SACD (track 2). Told him to close his eyes and "see" the instruments in space. Then I swapped in a normal power cord just for the SACD player (no, we weren't doing true blind testing). The other components still had their upgraded cords. Would changing one cord - while leaving other upgraded cords in place - make an audible difference? After a few seconds he says, "No freakin' way. I can't believe it." He could hear a difference. And here's another piece of anectodal evidence (sorry these posts keep getting so long!) When my DAC was out for repairs I was running my SACD player through my budget Yamaha 2-channel analog receiver (RX-395, 10 yrs old, $200). It has a built-in power cord so there's nothing to upgrade there. But I plugged it into my PS Audio UPC-200 line conditioner. The UPC-200's cord can be replaced. So I listened to the budget system with and without an upgraded cord in the UPC-200. There was still a difference. The cord to the line conditioner improved the Yamaha receiver (the SACD player was plugged into my other UPC-200 to control the variables). opaqueice Wrote: > > Edit - just to explain my comment about skepticism, it seems odd to me > that replacing the last two feet of wire before the device in question > can matter much, when the AC power has to travel so far and through so > much other wire to get there in the first place. > I agree. It does seem strange. Though think about AC detectors - you just wave it in the air and it can detect if there's an AC current or not. So clearly there's lots of EM weirdness being thrown out of AC lines. Shielding and this crazy counter-wrapped ground wire might help silence some of that EM interference that gets broadcast. And maybe it's really that interference, when brought close to and into your components, that fouls up some of the sound. Or more significantly - maybe it's when that EM interference passes near analog signal cables. They always say you should cross power cables at right angles if your speaker cables must cross. So clearly there's some concern of AC noise leaking into signal cables. I put vibration pods under my SACD player and didn't hear a difference. My roommate has his Shakti stone on my amp and I haven't bothered to do A/B comparisons. I switched from budget banana plugs to crimped silver spades w/Walker SST and I can't be sure I heard a difference. But the power cords were an obvious difference. So... back to the Squeezebox. When I get a chance I'll compare the Squeezebox DACs when plugged into a normal power strip vs the UPC-200 w/upgraded power cord. As for linear power sources - I haven't understood most of the talk and frankly am happy to tune it out. For critical listening I only care about the digital out and I'm sure that's excellent as-is. -- banzai ------------------------------------------------------------------------ banzai's Profile: http://forums.slimdevices.com/member.php?userid=5008 View this thread: http://forums.slimdevices.com/showthread.php?t=22000 _______________________________________________ audiophiles mailing list audiophiles@lists.slimdevices.com http://lists.slimdevices.com/lists/listinfo/audiophiles
