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Power Cords for M/L 13a B212 Make a difference ?

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ttocs

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So if the D'Agostino is on a 15A circuit and the breakers don't pop, then it's using less than 15 amps.
Correct. I was simply stating that to derive the performance the amp is capable of, it needs to be supplied via a 30A circuit. From dandagostino dot com: "The Relentless Monoblock can achieve its rated 1,500 watts into 8 ohms with a standard 15- or 20-amp household circuit, but achieving its rated 3,000 watts into 4 ohms and 6,000 watts into 2 ohms requires a 220-volt, 30-amp circuit of the type used for electric clothes dryers—something any electrician can install."

That's not how it works, actually. The breaker does not limit the amount of current delivered to your device, nor does it impede that delivery in any way.
Breakers definitely limit current to what they are designed for. This includes some amount of overcurrent.

What it does is pop when the current being requested is greater than its rating.
Correct, and most folks are unaware as to how much over the "Rated Current" the breaker will allow before a fault occurs.

Important circuit breaker characteristics include Rated Current, OverCurrent, Switching Time, and Thermal Tripper. OverCurrent, Switching Time, and Thermal Tripper all play a role in tripping the breaker under the conditions it is designed for with respect to exceeding the current rating. While it's not a "one size fits all" situation, most general household breakers for outlets allow for some amount of overcurrent for some amount of time - usually brief, like under 10 seconds (there are charts for each breaker noting the exact time based on all the variables). The more brief the occurrence, the more current is allowed to pass without fault.

For example, the breakers in my electric panel that are rated at 20A will allow 35A to pass for several seconds without fault. As a comparison, the 15A breakers will allow about 26A through for a brief amount of time. So I look at it this way, I can have a circuit that can allow 35A or one that allows only 26A for transients before thinking of getting "in the way".

So I think we're in agreement, but just wanted to clarify.
 

ttocs

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Actually to be even more specific the circuit breaker is designed to actually only allow up to 80% of the overall amperage. So if on a 15 amp breaker it would trip at around 12 amps of usage and a 20 amp at about 16 amps.
Actually, I think you are stating the 80% rule for calculating loads. For example, when we build a house we are required to present a load schedule with all appliances and permanently installed lighting. We are not allowed to go beyond 80% of the circuit breaker rated current. So your calculations are correct, but only for the requirement for circuit loading, not circuit tripping.
 

Brad225

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Yes I could tell the difference in Bass for sure; I mean it was easily noticeable. Now since I've been plugged directly into the wall the past few days I've noticed I'm picking up bleed over from some sort of electronic in the room whether from my system or from outside the house. We are in the country and have some neighbors who are into 2 way radios heavily. So that tells me I have to get some sort of conditioner or regenerator and soon. It only started happening after removing the Panamax. It's very irritating when watching a movie and it pops in during a quiet scene.

MC452 Amp will be staying plugged into the wall but the PreAmp and the Speakers will be plugged into whatever I decide on purchasing.

Thinking I'm going to have to spend some money on a quality unit. I'm going to be looking through the member systems and seeing what a lot of you are using. I already noticed amey01 has the Shunyata Hydra which I've heard great things about. Thinking I might stick with Nordost tho and go with their QRT QB8 and the QRT QKore1. But I'm not sure. Going to discuss it with others as well. I also like the PS Audio Power Plants.
A few months ago an EE friend of mine were checking the noise on the 20 amp circuit for the front end on my system.

With my Trip Lite power backup and older Shunyata 4 outlet Hydra that is plugged into the Trip Lite the line was dead quiet. With either one alone the circuit was dead quite.
When we plugged into the unfiltered circuit there was 2 way or commercial radio on the line. You could not make out which one it was. Interestingly it did not show up on other circuits in the room.

Even an older Hydra will take care of your issue.
 

Speedskater

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Actually to be even more specific the circuit breaker is designed to actually only allow up to 80% of the overall amperage. So if on a 15 amp breaker it would trip at around 12 amps of usage and a 20 amp at about 16 amps.
That 80% number is a design guide, say for a large lighting or heating system. The circuit breaker rating is it's continuous 3 hour rating. It's short time period capability is much greater.
Some home theater people have been surprised at the number of big power amps that can be played real loud on one 20 Amp circuit. (they do have to turn the amps on one at a time).
 

Robert D

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So if you set up a 30 amp circuit for the home theater ,how much could you run off of that? Would you need another 20 or 30 amp circuit if you had a lot of amps and other equipment?
Right now I'm running everything off of 1 regular circuit, im assuming its a 15 amp and I have no issues. As far as amps, just a receiver and the Aragon dual monoblock. Got everything plugged into a Furman conditioner. Guess if you had to use more than one outlet that you'd need need more than one power conditioner. Wondering what someone with 3 or more powerful amps would do.
 

Robert D

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Question. Every once in awhile the lights in the room will dim with the stereo. Id guess thats showing some limitations in power supply and that more might be needed? I get it worse in my study when printing pages.
 

Nuri58

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I guess when you convince yourself there is a difference, weather you can hear it or not, then the pleasure having such power cord is just what counts. My ears do not hear any difference - maybe the power I receive has less bumps maybe my ears should be improved. From the more tech. Point of view I have hard understand that the last meter of wire should make a huge difference, except if there is a power conditioner included and you have bad power fluctuations. Not least seeing the kind of wire used inside the gear not near the cost of these cables we are discussing.
 

Speedskater

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So if you set up a 30 amp circuit for the home theater ,how much could you run off of that? Would you need another 20 or 30 amp circuit if you had a lot of amps and other equipment?
In the US, you can't use 15 or 20 Amp receptacles in a 30 Amp circuit. Doubt that there are many amps designed for 120V 30 Amp circuits.

* * * * * * * * * * * * * *
continuing;
if you were to run a 30 or 40 Amp feeder from the main breaker box to a small 6 breaker box near the listening room. You could have 20 Amp circuits with 15 or 20 Amp receptacles.
You could then run many 1000 Watt amplifiers. But why?[/QUOTE]
 
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ttocs

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Question. Every once in awhile the lights in the room will dim with the stereo. Id guess thats showing some limitations in power supply and that more might be needed? I get it worse in my study when printing pages.
It means everything needs to get checked out.

If the lights are dimming, that's not good, and can be for a bunch of reasons. The lighting might be connected to the circuit for outlets, which would necessitate being separated - lighting is supposed to be on a separate circuit. At the very least the circuit the amps are using is not adequate. The electrical box might be overloaded. Some connections might be loose.

Bottom line, the dimming lights means there is not enough power being supplied to the amps. This is not opinion. If there was enough power going to the amps the lights would never be affected.
 

ttocs

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So if you set up a 30 amp circuit for the home theater ,how much could you run off of that? Would you need another 20 or 30 amp circuit if you had a lot of amps and other equipment?
Right now I'm running everything off of 1 regular circuit, im assuming its a 15 amp and I have no issues. As far as amps, just a receiver and the Aragon dual monoblock. Got everything plugged into a Furman conditioner. Guess if you had to use more than one outlet that you'd need need more than one power conditioner. Wondering what someone with 3 or more powerful amps would do.
I went nuts when I did some major work on the front half of the house. I have 6 20A circuits for the A/V at floor level, plus one 15A circuit for the projector that I don't use anymore. I did not do this because I thought there would not be "enough power" for all the devices, I did it to separate equipment from other equipment and to give all the equipment all the overhead in potential Current Demand they might ever want.

I could, so I did.

I went extra nuts in providing Isolated Ground for the 20A circuits. Using Hospital Grade outlets, not cheap btw, allows the isolated ground to remain isolated, plus the "bite" on these outlets is extremely strong so it's difficult to unplug devices.

Did I need 6 of these? No. But I use all of them. The non-amplifier stuff is on two Panamax M5400-PM 15A Home Theater Power Management boxes, and both boxes use the same 20A outlet. The amps are all plugged into the outlets directly, including the 13A's because there are two amps in each speaker and yes, I unplug them for thunderstorms.
 

JonFo

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So if you set up a 30 amp circuit for the home theater ,how much could you run off of that? Would you need another 20 or 30 amp circuit if you had a lot of amps and other equipment?
... Wondering what someone with 3 or more powerful amps would do.
You called? 😃

Yes, I have one 30 Amp 240v feed that powers an EquiTech Balanced power transformer (weighs >230Lbs) that provides the power for the A/V rig. Plus multiple independent 20 Amp 120v circuits, used most for ancillary gear, like the PCs, automation gear, etc.

As the guy on the site with the most amps/channels in a single system, I wind up with unique challenges. I needed to find a better way to sequence my seven power amps (18 channels total). So being into DIY, I designed and built something that would address my needs.

I created a high-amperage power distribution unit (PDU) that is remotely controlled and can sequentially switch big loads like power amps that are fed balanced power.

Since this solution is not ML or ESL specific, I posted the build thread (with a ton more pics) over on the AVSForum:




So the answer to your question is that sequencing is key. I've been very impressed by the SurgeX Access Elite, and recommend it.
 

Speedskater

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Bottom line, the dimming lights means there is not enough power being supplied to the amps. This is not opinion. If there was enough power going to the amps the lights would never be affected.
Well if it's not an opinion, then it sure is an oversimplification.
Humans are rather sensitive to small changes in light brightness. So if the lighting and amps are on the same circuit the possible change in audio power may be trivial.
 

Speedskater

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Yes, I have one 30 Amp 240v feed that powers an EquiTech Balanced power transformer (weighs >230Lbs) that provides the power for the A/V rig. Plus multiple independent 20 Amp 120v circuits, used most for ancillary gear, like the PCs, automation gear, etc.
That sounds like a great setup for a large top-shelf system (with 7200 Watts available continuously for over 3 hours).
Large isolation (or balanced) transformers wired as Separately Derived Systems are a wonderful pricey AC power solution. But balanced transformers bring with them a lot of rules & regulations and added costs. At the end of the day, the differences between these isolation and balanced transformer systems is very small.
 

ttocs

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Well if it's not an opinion, then it sure is an oversimplification.
Humans are rather sensitive to small changes in light brightness. So if the lighting and amps are on the same circuit the possible change in audio power may be trivial.
Let's put it this way, when I work on old guitar amps, and when I tested my tube audio amps after building them, I use a current limiting device: A lightbulb. (Thanks Uncle Doug)

So I repeat, when the lights dim it means the amps are not reaching full power.
 

Robert D

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It means everything needs to get checked out.

If the lights are dimming, that's not good, and can be for a bunch of reasons. The lighting might be connected to the circuit for outlets, which would necessitate being separated - lighting is supposed to be on a separate circuit. At the very least the circuit the amps are using is not adequate. The electrical box might be overloaded. Some connections might be loose.

Bottom line, the dimming lights means there is not enough power being supplied to the amps. This is not opinion. If there was enough power going to the amps the lights would never be affected.
Ive rarely seen it in the room with the amps. Its mostly in the study with the laser printer. The house is set up pretty good since we built it only 12 years ago and it is a good builder. Just seems we probably could have used another circuit for some things. I needed one dedicated for my treadmill too. When we build our next house I plan on getting things right. Kinda learn this stuff as you go along.
 

Robert D

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My father is a retired electrical engineer. ill have to pick his brain on this. He designed substations and all sorts of things for the utility company where we lived.
 

amey01

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Point of view I have hard understand that the last meter of wire should make a huge difference,
It's not even the last metre.....it is an abstract middle-bit, because if anyone has bothered to look inside the amps (or whatever they are connecting) you'll find some skinny runt of cheap cable!

So it's just a conveniently added piece of jewellery that happens to be the only part of a long equation that can be seen from the listening seat.

On another note, has anyone bothered to compare power plugs? I'm really not sure those dinky US-style plugs are the best.

1598566645882.png


I think Australian plugs must be a lot better:

1598566672356.png


But has anyone compared South African plugs......they look bloody awesome!

1598566710783.png
 

spkrdctr

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Let's put it this way, when I work on old guitar amps, and when I tested my tube audio amps after building them, I use a current limiting device: A lightbulb. (Thanks Uncle Doug)

So I repeat, when the lights dim it means the amps are not reaching full power.
You do know that BOSE for 3 decades and may still use lights as current limiting devices in their some of their speakers. They are the only ones I have ever known to actually use them in a speaker. It was for clipping protection.
 

spkrdctr

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Jonfo, you get the most engineered award for your power system. I would have never seen that without your pictures. Sometimes it is worth seeing something that is at the top level of use. I tip my hat to you. You should NEVER have a power problem. Ok, I'm just amazed. Too bad you couldn't sell that project to audiophiles. I see money in that.
 

rpokuls

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It's not even the last metre.....it is an abstract middle-bit, because if anyone has bothered to look inside the amps (or whatever they are connecting) you'll find some skinny runt of cheap cable!

So it's just a conveniently added piece of jewellery that happens to be the only part of a long equation that can be seen from the listening seat.

On another note, has anyone bothered to compare power plugs? I'm really not sure those dinky US-style plugs are the best.

View attachment 20890

I think Australian plugs must be a lot better:

View attachment 20891

But has anyone compared South African plugs......they look bloody awesome!

View attachment 20892
That's interesting. Years ago, my former boss who was an audiophile upgraded his plugs to "hospital grade". He said
that it really opened up the soundstage and tightened up the bass. He also said that he wasn't really going to
worry about his speakers and amplifier anymore, but that going forward he was only going to concentrate on cables and plugs instead.


1598630787022.png
 

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