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In Reply to: Re: Irresponsibly wrong. posted by Ted Smith on September 22, 2003 at 08:49:02:
Hi TedWhat you say genuinely astonishes me. I can understand that unshielded AC cables in the usual tangle of wires at the back of ones rack is likely to upset signal cables, so I'm fully in favour of changing to screened cable. However, when you objectively consider what happens with the AC once inside the equipment, all this talk of megabucks cables makes no logical sense to me. Firstly as suggested before, the wiring between the socket and transformer is unlikely to be much better than what's in OEM cables. Then what happens? The AC goes into a transformer - hundreds of coils of copper wire doubled back on itself - the supply going in and out of the primary winding. This causes a fresh AC supply to be generated in the secondary coil, which has no physical or electrical contact with the primary. One wonders how imperfections in the AC cable can possibly adversely affect this new supply, now in the independent secondary winding. The rest of the equipment's power circuit rectifies, smooths and stores this secondary supply for use by transistors, valves, etc. In other words it tries to mimic a battery. Surely a well designed circuit can cope with an incoming supply deprived of a $1000 cable for the last few feet? As I say, it is astonishing to me that this should be the case and I would dearly like a logical explanation of physics I have may have missed.
I am happy though to believe that a decently designed amplifier is not adversely affected by a standard AC cable in the same way my washing machine washes just as well with an OEM cable as a $1000 one (OK I'm jesting, but you get the point!). Otherwise, as I have suggested earlier, manufacturers would not put up with grotty AC.
Incidentally even Maggie Thatcher, bless her heart (if she actually hadf one), admitted to spending 3 hours a night in bed. Plenty of time to recharge batteries!
I'm off to listen to music via my sub $50 AC cables - doesn't Eva Cassidy have an astonishing voice?
Peter
Follow Ups:
What you say about the internal transformer is only partial correct.
If it was a "perfect transformer" like those tault at college then you are correct. BUT in the REAL world with real components nothing is that simple. firstly there will be a coupling between the primary and seconday windings caused by the phyical spacing between them. ie they are capacitivly coupled, this will let through noise.
secondly the transformer core dependant on its material constuction, will also allow non 50/60Hz frequency coupling.
thirdly any RF on the line will travel on the outer surface of any metal, it can jump across the transformer and capactivly couple itself to the equipments DC line without too much problem.Since most equipment manufacurer dont "design their" equipment to any great degree of noise immunity or rejection (those that do produce broadcast quality suff at a large price multiplier), we are left with a far less than perfect ("it will do @ that price") level of equipment.
Hence we are left to the snake oil saleman, and the genuine engineer/designer, and ferrite rings, JR & CVH and others to try and solve the problems. This is one of the reason that so much discussion goes on about mains, and cables in general. The others are lack of indepth knowledge, arrogance, ignorance, pride, prejudice, stupiity or any of the other deadly sins.
Incidently the platting of any wire is known to reduce the noise level of a signal on it. Kimber and others have made a lot of money out of this known fact. and not a serpent in sight.
HowdyWell, not everyone is like you. I need sound to sleep. Otherwise other distractions keep me awake.
I, Jon and others have answered, or at least tried to answer your other questions. I'm an EE and fully understand where you are coming from and used to be just as sure of myself and just as wrong. Listen for yourself, things make a difference and everyone has different systems, preferences and pocketbooks. You don't seem to understand that the components we use don't exactly match their mathematical models. A good engineer understands the limits of their models and keeps an open mind when things don't work like the math says it should. Better engineers figure out what's wrong with the models, refine them and build better products.
Is adding a $1000 power cord the most cost effective thing to do? It depends on your budget, how much your time is worth, how much custom engineering you are willing to do or pay for, etc. I never claimed it was the best for you. You also may note, that I don't use $1000 cords myself, but I have friends who do and I sure as heck can tell the difference in their systems when cheaper cords are used.
Once again, the environment inside a unit isn't the same as outside, shielding is the most obvious difference. Also some of us have replaced internal point to point wiring with better quality wiring, others of us have bought components with high quality wiring already built in.
Ralph Vaughn Williams spinning here.
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