Ben Duncan has actually compared circuit breakers and is convinced that some models ruin the sound once they have tripped. He also sells a hardwiring box to get away from pesky power plugs for your system Pure Hardwire - 12 Way audio standard mains distribution system by Ben Duncan
Mark: you are trying to be hall monitor again. John is old enough to know full well what he is doing.
Well, testing with your ears is the best way to tell differences in power cords, for example. I used my STAX vacuum tube driven headphones to test several typical line cords, and added 'filters' as well. The differences were subtle, but in direct comparison, they were real. Sometimes the sound changed in both good and bad ways at the same time. For me, a relatively skinny (18ga) commercial line cord sounded BETTER than an 14ga cord by the same manufacturer (Belden). Why? How could this be?
I found that adding a wrap around steel line filter, (sort of a transformer core). It made the sound less 'tizzy' but it also sounded a bit 'underwater'. Good choice? Depends.
Finally I listened to my first Bybee powerline filter, and it did more with the least compromise. This was more than 20 years ago. That is how I discovered the Bybee devices, and I have never looked back.
Do I think that power line cords should cost big money? No, and I think that even the best, are but one factor in overall sound quality. There is far too much profit made in accessories, usually by the audio dealer, than there should be, and this is a sad situation. Still, I have heard the differences.
I found that adding a wrap around steel line filter, (sort of a transformer core). It made the sound less 'tizzy' but it also sounded a bit 'underwater'. Good choice? Depends.
Finally I listened to my first Bybee powerline filter, and it did more with the least compromise. This was more than 20 years ago. That is how I discovered the Bybee devices, and I have never looked back.
Do I think that power line cords should cost big money? No, and I think that even the best, are but one factor in overall sound quality. There is far too much profit made in accessories, usually by the audio dealer, than there should be, and this is a sad situation. Still, I have heard the differences.
John, if you change a power cord and the sound of your amplifier changes, might not that suggest there is some problem with line rejection in your amplifier power supply? It's not clear that a power cord has a sound of it's own, so much as it might have electrical characteristics that could interact with a particular circuit it is connected to. Particularly so if the amplifier had something like a very HF RF oscillation above what your o-scope could see. But, even if nothing so dramatic it still sounds more like some kind of amplifier problem.
On the room acoustics we were discussing. In case anyone didn't know. Earl Geddes has made his book on home theater available as a free download
GedLee LLC
Although the video part is well out of date the sections on acoustics, hearing and practical guide to building a room for good sound are well work reading.
GedLee LLC
Although the video part is well out of date the sections on acoustics, hearing and practical guide to building a room for good sound are well work reading.
Sorry Big Allis rules, my father worked on the ore mixings for the castings.
https://en.wikipedia.org/wiki/Big_Allis
You're wasting your time the Bybee's are powered by garbage physics, http://www.rexresearch.com/meg/meg-debunked.pdf
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Markw4, I usually find that power amps are the least of my worries when it comes to power cords or even Bybee devices. It is sources and preamps that seem to make the biggest differences.
I normally use normal, commercial, 14ga power cords for my amps. Could I do better? I think so, but I haven't bothered recently. I have fairly fast scopes,(350MHz) and a pretty good FFT analyzer (SR-1) and if I had oscillation problems, I am pretty sure I would find them.
Certainly, the CTC Blowtorch has its own custom power cords, and I tend to use a special power cord for the STAX Headphone amp. For the rest, I use a special power line conditioner. I really don't like putting a lot of time and money into interconnects or line cords, but plenty of my associates do. They often design their own, so they seem extra sensitive to their importance. Still, I always use better than Radio Shack for my audio reproduction.
I normally use normal, commercial, 14ga power cords for my amps. Could I do better? I think so, but I haven't bothered recently. I have fairly fast scopes,(350MHz) and a pretty good FFT analyzer (SR-1) and if I had oscillation problems, I am pretty sure I would find them.
Certainly, the CTC Blowtorch has its own custom power cords, and I tend to use a special power cord for the STAX Headphone amp. For the rest, I use a special power line conditioner. I really don't like putting a lot of time and money into interconnects or line cords, but plenty of my associates do. They often design their own, so they seem extra sensitive to their importance. Still, I always use better than Radio Shack for my audio reproduction.
John, that sources and preamps would usually be more sensitive to power problems seems not unreasonable.
And I would agree with using reasonably good quality cords rather than junk.
It also seems understandable that some of your associates could be extra sensitive in a way that you or I might not.
But, getting back to the question, we have a few people over in the 24/96 listening test thread who appear to be able to correlate recorded track sound quality with measured op-amp performance, at least to some extent. Being able to distinguish something about the sound of a single stage noninverting op-amp circuit is pretty good, it seems to me, especially when done from a recording. But, I don't know if people who can do that also claim to be able to hear power cords.
If they do claim that, I would be interested in performing similar tests, or somehow getting to the bottom of whatever might be going on.
Right now it seems pretty hard to make much sense of it, and if it's true, I would still say it suggests problems with the preamps, sources, poweramps, whatever, more than the power cords.
The idea is that equipment needs to be insensitive to most common power quality variations. And I would put a power cord issue into that category of power quality.
And I would agree with using reasonably good quality cords rather than junk.
It also seems understandable that some of your associates could be extra sensitive in a way that you or I might not.
But, getting back to the question, we have a few people over in the 24/96 listening test thread who appear to be able to correlate recorded track sound quality with measured op-amp performance, at least to some extent. Being able to distinguish something about the sound of a single stage noninverting op-amp circuit is pretty good, it seems to me, especially when done from a recording. But, I don't know if people who can do that also claim to be able to hear power cords.
If they do claim that, I would be interested in performing similar tests, or somehow getting to the bottom of whatever might be going on.
Right now it seems pretty hard to make much sense of it, and if it's true, I would still say it suggests problems with the preamps, sources, poweramps, whatever, more than the power cords.
The idea is that equipment needs to be insensitive to most common power quality variations. And I would put a power cord issue into that category of power quality.
Unlike many here, I take my power supply designs VERY SERIOUSLY. I use special fuses, or circuit breakers, transformers (low leakage), inline
common mode chokes, hi speed soft recovery rectifiers, double or triple series active filtering, polystyrene bypass caps, etc, etc. I really don't think that I have made any serious mistakes or oversights, although I have learned a lot recently from Ed Simon (that is what I define as continuous progress). Still, with my, or other designs, such as STAX, etc, I find that line cords can be important. I can't understand why you can't consider that as well, rather than just blaming the equipment itself.
common mode chokes, hi speed soft recovery rectifiers, double or triple series active filtering, polystyrene bypass caps, etc, etc. I really don't think that I have made any serious mistakes or oversights, although I have learned a lot recently from Ed Simon (that is what I define as continuous progress). Still, with my, or other designs, such as STAX, etc, I find that line cords can be important. I can't understand why you can't consider that as well, rather than just blaming the equipment itself.
Jan's silentswitcher. Best present to source and line level DIY in a very long time. All power supply angst killed off in one cheap and handy board.
It's good to know a leading amp designer feels the same as me. I wish we someday will find the audio measurements method that is more reasonably correlated to our perception.
When we tested several different power cords in a recording studio, we found Mytek DAC is very sensitive to the power cord difference. We could not really hear any meaningful difference with the other equipments tested. I don't still know why...
More importantly, we found that the plastic molding of the power plug is the main source of the coloration. In the recording studios, Mogami Bantam patch cord with plastic molded plug is common, but they are notoriously horrible sounding line cables. Mogami cables are simply great, though. BTW, Greg Calbi, a very famous mastering engineer once showed me a collection of the line cables for coloration, and he said he uses them as passive filters when he masters.
More importantly, we found that the plastic molding of the power plug is the main source of the coloration. In the recording studios, Mogami Bantam patch cord with plastic molded plug is common, but they are notoriously horrible sounding line cables. Mogami cables are simply great, though. BTW, Greg Calbi, a very famous mastering engineer once showed me a collection of the line cables for coloration, and he said he uses them as passive filters when he masters.
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Okay, I would be happy to tell you why. The difference between a line cord and a piece of Romex is very tenuous. If a power cord is making an audible difference, then the Romex probably is too. But you can't so easily change the Romex. Therefore, you probably need to fix it in the amp. I hope you can see my concern here.
Or, maybe if you don't think Romex can cause the same problems as line cord, maybe we should just wire up amps with Romex and be done with it. Why struggle with special power cord designs when the perfect answer is so handy?
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Well, maybe there was some problem with the Mytek DAC.
It would be very interesting to hear how it was determined that the plastic molding was a problem though. Maybe it was conductive? Or maybe it chemically reacted with cable terminations in the connector? But how did you isolate it down to the molding?
Powercords sound different. They can act like a mini filter. I don't believe anything is necessarily wrong if a powercord affects equipment. Consider this, there are a lot of parasitic qualities that may be present and not be "bad engineering" but affected by parasitics between powercord/socket to chassis. There isn't exactly wrong or right answers to many things... just choose powercords with identical guage H/N, high copper purity, low inductance from twist/braid, copper plugs.
You can get JPS in wall wire that is 10ga twisted, instead of romex.
You can get JPS in wall wire that is 10ga twisted, instead of romex.
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