This whole discussion sounds like much ado about nothing, or something so microscopic in effect that it's far below real (not imaginary) audibility. With a power cord, once ampacity and safety requirements are met, it's a done deal. Cosmetics can play a role if you enjoy looking at power cords, I 'spoze. Since the cords are usually hidden behind equipment, there wouldn't be much to see.
If anyone needs a copy of the letter, I can send a PDF.
With due respect to "the old timers" PN junction ringing was certainly known to ham radio guys operating mobile with switch mode power supplies. It's discussed in William Orr's "Radio Handbook". It's also in my 1962 ARRL "Mobile Manual".
Actually - try that, with instrumentation, and you find it makes LF noise at the AC mains input worse, due wot resonances with the mains AC wiring and attached local loads.
I know, I tried it. Big X2 capacitance on its own = not a good answer.
Really? I'd like to see some of your measurements.
I do know the electrical companies spend a lot of money installing mega-tons of PFC caps in their stations. The resonance this creates is a *nice to fix".
Still, a big local X2 is not a bad 1st step, to be followed by proper snubbing's of the transformers, rectifiers, and smoothing.
Okay. If it helps at all, there is something called a 'threshold of audibility.' It is an estimate of an average for a population. That means that it is a statistical estimate of a threshold level where 50% of the population can't hear the effect, and the other 50% of the population can still hear the effect.
Curiously, more than 50% of people seem to think they are in the more sensitive 50% of the population. Perhaps its for the same reason that most people think they are better than average drivers.
Even if that were true, some people use better speakers: https://www.soundlabspeakers.com/wp-content/uploads/2019/07/The-Complete-White-Paper.pdf
I have said that if someone cannot hear the improvement a aftermarket power cord makes, that is great for them! Then they can save time and money trying to find the best sounding ones for their equipment. 🙂
If you have a good PS Audio Regenerator or a Monster HTPS 7000 MkII, then it shouldn't be necessary to mess around with power cords. Plus, you will be better off sound-wise.
That said, sometimes replacing wall outlets with new 'Hospital Grade' outlets can help make a better connection.
In this video you can listen to two well know aftermarket power cords and see if you hear the difference. Read the comments below the video and see that many people do hear a difference, and they don't know which one they are listening to. A blind YouTube test. Big Jay tests lots of audio equipment.
I can confirm this is entirely false: many moons ago, I heard the difference between MP3's and CD's off some $1 speakers in my car. I repeated the experience with some $20 PC speakers in my office, and the difference was consistent and not subtle. Now I drive with Hires flac exclusively.
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I don't miss the point. You could hear the difference using two tin cans joined by string!
What has this got to do with hearing the extremely subtle effect that a power cord is said to have on the sound of an audio system?
What has this got to do with hearing the extremely subtle effect that a power cord is said to have on the sound of an audio system?
So now I get you to admit the masking effect of less than superlative speakers is not that bad.
I'm done fighting. Enjoy your tin cans.
I'm done fighting. Enjoy your tin cans.
Power cables may act as filters that don't sound like ferrites. Again, if you clean up the AC power properly, power cables should have much less effect. If they still do have some effect, it probably has to do with the backward looking impedance and or noise of the power supply relative to a very local upstream filter.
Try using ground loop buster circuits such as tombo described or something like this:
Use it to help isolate audio circuit ground from AC power ground in each chassis.
IOW, power cords can't be black magic, probably not exactly what Shunyata marketing materials say, etc.
Look, I know some people who design high end audio for a living and have done so for many years, sometimes as consultants to well known companies. They say power cords need to be decent, power connectors need to be high quality, but after that don't try to fix the sound with power cords. Use an old-style Regenerator or a power conditioner such as the one I suggested. Such devices are not all equally good, so choose wisely regardless of marketing claims.
Try using ground loop buster circuits such as tombo described or something like this:
Use it to help isolate audio circuit ground from AC power ground in each chassis.
IOW, power cords can't be black magic, probably not exactly what Shunyata marketing materials say, etc.
Look, I know some people who design high end audio for a living and have done so for many years, sometimes as consultants to well known companies. They say power cords need to be decent, power connectors need to be high quality, but after that don't try to fix the sound with power cords. Use an old-style Regenerator or a power conditioner such as the one I suggested. Such devices are not all equally good, so choose wisely regardless of marketing claims.
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If you use that ground isolator, the surge rating of the bridge is 65 amps.
The bolted fault current at an outlet 100 feet from the service panel is 1000 amps assuming #12AWG. Should that isolator be required to withstand that level of bolted fault, the diode (which is just a molded assembly of diodes encapsulated using 2851 MT "stycast") probably would lose containment. The concern would be, will the line breaker trip magnetically faster than the diode explodes. That bridge design does not fail short under those conditions, but open. If it opened in less than one line cycle (16.6 mSec), the isolator will no longer be protecting humans nearby.
I would never recommend something like that in the path of a safety bonding circuit.
John
The bolted fault current at an outlet 100 feet from the service panel is 1000 amps assuming #12AWG. Should that isolator be required to withstand that level of bolted fault, the diode (which is just a molded assembly of diodes encapsulated using 2851 MT "stycast") probably would lose containment. The concern would be, will the line breaker trip magnetically faster than the diode explodes. That bridge design does not fail short under those conditions, but open. If it opened in less than one line cycle (16.6 mSec), the isolator will no longer be protecting humans nearby.
I would never recommend something like that in the path of a safety bonding circuit.
John
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