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ttocs

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Good quality receptacles with a strong "bite" are what I have. This is a feature of hospital grade outlets so cords don't become loose, or worse - unplugged, very easily. Hospitals don't want anyone dying because a life safety device power cord becomes loose or unplugged by accident.

In my case I wanted to be sure there's enough amperage for everything with lots of extra for transients. So my system uses seven 20A circuits with Isolated Ground Hospital Grade receptacles.

Does it change how the system sounds? Well, if all of my components were plugged into just one 15A circuit, then the system would sound worse because there's simply not enough amperage to go around, the electricity is effectively choked off. So the way I think about it pretty practical. Add up the peak power needed for everything, consider the total to be 80% of the amperage supply needed and this is the minimum amount I'd recommend. I wanted more. Then use quality outlets, not multi-hundred-dollar outlets, but not cheap either. Mine were less than $50 each, made by Hubbell. Nothing exotic.
 

Robert D

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Good quality receptacles with a strong "bite" are what I have. This is a feature of hospital grade outlets so cords don't become loose, or worse - unplugged, very easily. Hospitals don't want anyone dying because a life safety device power cord becomes loose or unplugged by accident.

In my case I wanted to be sure there's enough amperage for everything with lots of extra for transients. So my system uses seven 20A circuits with Isolated Ground Hospital Grade receptacles.

Does it change how the system sounds? Well, if all of my components were plugged into just one 15A circuit, then the system would sound worse because there's simply not enough amperage to go around, the electricity is effectively choked off. So the way I think about it pretty practical. Add up the peak power needed for everything, consider the total to be 80% of the amperage supply needed and this is the minimum amount I'd recommend. I wanted more. Then use quality outlets, not multi-hundred-dollar outlets, but not cheap either. Mine were less than $50 each, made by Hubbell. Nothing exotic.
If you try to draw more than 15 amps from a 15A circuit, won't that trip the circuit breaker? I'm thinking you wouldn't experience equipment being choked off because the breaker would kick off? Isn't it all or nothing? So if the breaker isn't tripped, isn't there enough power?
 

Stefan_DR3

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If you try to draw more than 15 amps from a 15A circuit, won't that trip the circuit breaker? I'm thinking you wouldn't experience equipment being choked off because the breaker would kick off? Isn't it all or nothing? So if the breaker isn't tripped, isn't there enough power?
No they can take instantaneous peaks of a lot more current without tripping. It's how Bryston justifies selling KW amps and massive power conditioners.
 

Don Camillo

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Wow I this is a very actual topic for me as I recently bought a new Gigawatt 16A Circuit breaker which opened up everything with a more clear and stable sound, wider stage etc, compared to the cheap house circuit breaker....

I too saw the 20A inlet I wanted to use and thought would be better as inlet for the power distributor from where 15A connectors go to all equipment.... so I asked my Gigawatt seller who is also Furutech dealer and specialized in power from the mains to the system.

According to him with my 2x140 watt amp and the rest of the system 15A would be more than enough...
Also the Gigawatt 16A Circuit breaker would be more than enough for the entire system.

It definitely doesnt sound choked at all... but an honost compare would be if I had a 20A version to compare it with...
 

Stefan_DR3

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Good quality receptacles with a strong "bite" are what I have. This is a feature of hospital grade outlets so cords don't become loose, or worse - unplugged, very easily. Hospitals don't want anyone dying because a life safety device power cord becomes loose or unplugged by accident.

... Nothing exotic.
I wholeheartedly agree.

Back in the Audio Asylum days (20+ years ago) we used Bob Crump's DIY power cord recipe that consisted of Pass & Seymour "spec grade" plug and outlet. Spec grade gives you the same build quality and grip of death as "hospital grade" but at an even lower price and easier to find. The metallurgy is better than your average stamped nickel "contractor grade" and that supposedly makes a difference too. They might still sell these at Lowes.

15A Male plug: P&S 5266-X
15A Receptacle: P&S 5242-I (they come in various colors; I is for ivory)

I have been using these for 20 years and never looked back. I even took them with me when I moved to a new house.
 

Robert D

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No they can take instantaneous peaks of a lot more current without tripping. It's how Bryston justifies selling KW amps and massive power conditioners.
Ok, but just short bursts? Any idea how long it can last and not trip the breaker? I was not aware of that.
 

ttocs

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If you try to draw more than 15 amps from a 15A circuit, won't that trip the circuit breaker? I'm thinking you wouldn't experience equipment being choked off because the breaker would kick off? Isn't it all or nothing? So if the breaker isn't tripped, isn't there enough power?
Well, I was really just making a point using an extreme example. In my case, when I add up all the peak watts for my components it comes to around 8000 Watts, which equates to about 66 Amps, but this doesn't allow for any headroom - which I'm a big fan of having.

Yes, there's a good chance of popping a single 15A breaker. But the big takeaway here is to try to point out how the sound can suffer when components don't have the power they need to operate freely.

When I bought my Krell amp, it had been on display but not plugged in. The box had been tossed away, and they gave me the WRONG cord. I didn't know about the cord for quite a while. The sound was great, much better than my previous Carver amp, but over time, and when using high volume, I found there was still something irritating about the higher frequencies. So, after trying various things per the usual try this, try that stuff, I looked at the Krell power cable. It was a Krell supplied cable, but it was designed for their CD player and was rated for 10 Amps. I made a new 20A power cable and BINGO! No more irritation!

This is to point out that while the sound was very good, it was improved by simply giving the amp the FULL 15 AMPS that is required as stated in the manual.

I've tested the Amperage draw when using two channels of the Krell amp with the new power cable. Using a meter rated for 10A, it measured almost 8A peak using 1ms peak/max/hold measurement. This was not peak volume, but it was the most I was willing to put my speakers through just for a test.
 

audioxcel

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I fried a tube amp once when the power cord plug became loose in the receptacle. Two tubes flashed over and their grid resisters blew. I think the bad contact created a high current surge.
 

Robert D

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I guess our home's outlets must be decent because they are really tight. Sometimes I feel like I have to pull really hard to get the plugs out of the outlet. One time I ended up grabbing the plug too far down and my hand must have touched the metal prongs when I pulled it out. I got shocked.
 
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