Check out this link from headfi about a discussion linking to ABX testing of highend equipment.
http://www.head-fi.org/forums/f133/abx-tests-367485/
http://www.head-fi.org/forums/f133/abx-tests-367485/
Sonusthree said:
A computer that has been cleaned of spyware/trojan, removal of startup programs and defragmented will definitely run quicker and with less latency than without. It can be timed with a stopwatch. It can also be observed by looking at the read/write cycles of the hard drive activity lights. I know on my computer, the hard drive crunches hard if the disk is fragmented and needless programs are being run in the background. I dont see how this relates to the discussion at hand.
Stopwatch?? Last comp I cleaned had 1500 pieces of spyware.. I coulda used a calender...dietcoke said:
Cheers, John
rowemeister said:
"Service drop" is defined by NEC:: ""The overhead service conductors from the last pole or other aerial support to and including the splices, if any, connecting to the service-entrance conductors at the building or other structure.""
On this side of the pond, the aluminum wiring can be the cable from the meter pan to the main breakers in the panelboard in the house. It will be type SE or USE.
This is the standard house feed on this side of the pond, east coast. It refers to a single bushing transformer on the pole. On the west coast, I've seen two bushing xfmrs..
ps..note that I didn't think to include the meter...oops..
PPS..note that there are grounds everywhere....the three phase powerfeeds on the top of the pole( in residential areas, only one phase is up there). The pole neutral will be earthed within a pole or two of your house, the house will be earthed where the service entrance comes in, you'll have a bonded ground to the water pipe feeding your house. And the ground and neutral are tied at the panelboard. But the duplex grounds never carry the current from the appliance.
How could a line cord possibly affect the stereo sound???
Simple, it alters the ground loop formed by the equipment. Either how the cords radiate magfield, how they intercept, the overall ground loop resistance...several things..
It causes hum when it is worst case. And it has a frequency dependence.... so to assume that haversine draw from the amp does not couple into the ground loop, is an assumption based on no information.
It does. To what extent is unknown.
So there, I've applied engineering and physics to the problem..anybody else care to actually join in??
Cheers, John
Attachments
dietcoke,
I think sonus is talking about perception, and how it can be skewed by outside factors. Why an expensive power cable will sound better.
I think sonus is talking about perception, and how it can be skewed by outside factors. Why an expensive power cable will sound better.
Ah thanks
I've double checked and it seemd in the UK that all wiring is copper.
What do you expect to read on a loop test (Ze test).
I'm trying to see if your mains impeadance is higher to the house and therfore a low ohm cable would not really benefit.
edit: UK earth is connected to neutral at the sub station (tx).
Brent
I've double checked and it seemd in the UK that all wiring is copper.
What do you expect to read on a loop test (Ze test).
I'm trying to see if your mains impeadance is higher to the house and therfore a low ohm cable would not really benefit.
edit: UK earth is connected to neutral at the sub station (tx).
Brent
dietcoke said:
Yes, the computer was measurably faster. My point was that she was very sure that I'd also cleaned the outside. I had not.
My point? Perception is not an accurate way to determine most things with any certainty.
I own ordinary mains cables and 'special' mains cables. I usually 'hear' a positive difference but I certainly don't trust my own perception. I am skeptical despite my personal experience.
Edit: Cheers Poobah, Nice to see you around here agin.
Panicos K said:
No. There are now 8 pages arguing subjectivity. I find that strange.
Personally I am a naysayer but if there are those who hear, or think they hear a difference, then who am I or anyone else to say it's not so? Seems rather pointless when there are so many things in this field to discuss that have far more relevance. A mains cable is so far down the list of the things to consider that I am amazed at how much attention this gets. It's like discussing what type of lug nuts are best to hold the wheels on your car.
row meister,
About 10% of the power generated is lost in the form of heat before that power reaches your outlet. You could back into an "effective" impedance calc with that figure.
Cal,
Part of what drives this this is based on what you've said. The weakest link in the whole chain is nearly always the speakers. It owould be nice to see people put their money there.
🙂
About 10% of the power generated is lost in the form of heat before that power reaches your outlet. You could back into an "effective" impedance calc with that figure.
Cal,
Part of what drives this this is based on what you've said. The weakest link in the whole chain is nearly always the speakers. It owould be nice to see people put their money there.
🙂
Rhodium???
I was once designed and built oral mirrors for a dentist. He insisted that the mirrors be curved so that that he could look around corners. Despite my warnings, he was dissapointed in the prototypes becuase the images were distorted... takes all kinds I guess.
I was once designed and built oral mirrors for a dentist. He insisted that the mirrors be curved so that that he could look around corners. Despite my warnings, he was dissapointed in the prototypes becuase the images were distorted... takes all kinds I guess.
poobah said:
I've no idea how that would be done by using the 10% figure.😕 😕
Here in the USA, the source impedance presented to residential customers is limited by the utility provider. The reason for this is to limit the bolted fault current that can be delivered to the panelboard within the house. If you examine the panelboard, you will find that it is rated for a fault current, typically this will be in the hundred or so kiloamp...the breakers are typically rated for fault currents of 10 kiloamps.
So you could take the wiring resistance drops from the pole transformer to the panelboard, use 240 volts as the voltage, then back into the lowest overall system impedance necessary to produce 100 kiloamps.
But quite honestly, it's an exercise in sillyness. The NEC does not give drop figures to the outlet, but gives a recommended total line drop of 4 percent in order to limit the problem of lights dimming as a result of load. And to top it off, source impedance is not the reason a line cord would alter a system. If it did, then the supply is terribly designed, and you probably need to upgrade your house wiring.
Industrial consumers are not impedance protected by the utility. As a direct result of efficiency gains in power delivery (such as better transformers which dissipate less heat), the bolted fault current available to industrial buildings is causing an ARC flash problem. Now the bolted fault currents are sufficiently large to breach the containment structure of breakers and switchgear. This has forced everybody to alter their safety procedures. Now, class 4 gear requires the "back to the future" 40 cal suit.
Cheers, John
Don't make it so hard John...
If your plugging in a 9 ohm load... it is simple enough to say that the EFFECTIVE/virtual/apparent/psuedo impedance looking back is 1 Ohm. You know... napkin stuff... keep it lite (30% less).
😀
If your plugging in a 9 ohm load... it is simple enough to say that the EFFECTIVE/virtual/apparent/psuedo impedance looking back is 1 Ohm. You know... napkin stuff... keep it lite (30% less).
😀
poobah said:
Hey, I hadta learn this garbage...gotta use it somewhere....😉
So then, if I dead short the outlet, max current would be 120 amperes?
I believe it would be a tad higher..
Cheers, John
ps..didn't realize that word was auto-deleted..sorry bout that..
poobah said:
I couldn't agree more. It's the only link that can have as much effect on the final product.
Nice to see you posting again, the forum was a little hollow without you.
Yeah yeah,
Keep it lite... we're having enough trouble here explaining why splicing a kite string with anchor chain is a bit silly.
😉
Yes Cal,
We have all this magnificent off-the-shelf gear with errors in the 0.something% category... and then come the drivers! I have been learning just how important walls and floors etc... are to whole effort. And these are Cheap fixes...
Keep it lite... we're having enough trouble here explaining why splicing a kite string with anchor chain is a bit silly.
😉
Yes Cal,
We have all this magnificent off-the-shelf gear with errors in the 0.something% category... and then come the drivers! I have been learning just how important walls and floors etc... are to whole effort. And these are Cheap fixes...
Yes, I believe the room is the least recognized link and of far greater importance than it's given.
poobah said:
Well, lets look at why the trouble.
1. miles and miles of wire without consideration of where the tie point for the system reference ground is bonded.
2. Completely ignoring how that ground reference is shabbily handled by consumers...both end users, and designers.
150 dB S/N. Do you think that would have been possible if you attempted to reference two seperate chassis and signal grounds to bonded structural points on opposite sides of a building? My office has two outlets, one on each side, and the ground is between 400mV and 1.5 volts AC different...and there is no ground current flowing. It's all Faraday's law of induction at work.
There is no national holiday where Faraday is allowed off..😀
Why is the shabbily treated home audio ground system somehow ignored in all these threads?
Cheers, John
Hartono,the one I have is the FS-2.0,ugly black,although I have tried most of those.At least I won't be accused I've chosen the best looking one-although tastes vary even here-.Regarding price,it is not cheap by some standards,I find it quite logical for my standards and for what it is:good quality copper,polyethylene insulation(no PVC troughout),heavy copper shield foil,solid 12awg size and as I said I liked its sound after careful listening.Being made in Japan,is also a reason for being a little more expensive than some others.
jneutron said:
Al least in my case, circulating currents in the screen (and the parallel earth conductor run along side the lines) have minimal influence on the audio electronics, for the simple reason that I tend to run balanced lines and don't design pin one problems into my gear (And fix the regrettably common ones I find) .
Earth loop currents are completely harmless as long as you can keep the voltages thus developed from coupling into your audio signal reference (which should be locally produced within each box and never leave it).
Designing audio gear to be immune to ground hash is just not that hard, and then a volt or so of ground difference just causes screen current to flow and while it may add some SCIN, that is easily dealt with.
The guys who design broadcast gear all without understand how to do this, as does every good instrumentation engineer, why has it taken general audio so long to wake up?
Regards, Dan.
- Status
- Not open for further replies.