Do power cords matter?

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I do agree that a dedicated 20 amp line is key for a amplifier..

Hey - have you guys in the US tried upping your line voltage to 240v?

I reckon a 240v line is key for an amplifier, don't you reckon Justin?

"Everything makes a difference", and what an amazing difference 240v makes!!

You don't know what you're missing out on :)

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I'm joking just so you know.........just trying to add a little light-heartedness to it.

But there is a serious side that can be argued with more believability than power cables. Doubling the line voltage by definition halves the effect of any voltage disturbances. Also by definition, we are halving the current requirement to operate at the same output as well. Less current demands and more line stability could be seen as a good thing. Except you can't change your voltage so you don't get up tight about it. So why with power cables?
 
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Why the need for different power cords?

• Some power cords are poorly constructed (poorly terminated and/or too low a gauge size for required application) and can be improved upon.
• The power supplies of some audio devices are inadequately designed and, therefore, don’t do the job of properly supplying clean power to the electronic ccts that follow.
• The deceitful marketing practices of audio companies who take advantage of unsuspecting audiophiles who are influenced by these practices.
• Psychological biases.
• Some combo of the above 4.

Instead of shelling out big bucks for a power cord why not buy an isolation transformer. It’ll condition your lines, eliminate all EMI/RFI noise, ground loops and act as a surge suppressor.
 
I use upgraded power cords on all my equipment. But then again, I also have dedicated 20 amp circuits with isolated grounds and a PS Audio P10 power regenerator feeding my equipment through those upgraded power cords. That, my friends, makes a clearly audible difference. :D
 
So you think you're a better amplifier designer than the highly qualified engineers you paid so much to design the amplifier for you in the first place?

Hi amey01,

I honestly like discussions like this, there is always some hints and truth in every comment, thank you.
Please allow me to comment on your last sentence quoted above: No I do not think I am a better amplifire designer than the one that origianlly designed it. In fact I happen to know the designer personally very well. The big difference is that all HiFi Producers in this world are doing what they are doing to earn Money which to a certain extend force them to compromise when it Comes to choice of components. I was not talking about changing the design of the amp itself but to upgrade components, connecting cables and PSU as I do not expect to make a living out of what I am doing.

Within the last year or so, I have upgraded my CD Player, Amps and the Speaker cross over in my old (TDL Monitor Compact) and new (ML Aerius) loudspeakers with a great positive Impact. I am positive that I would have paid 10x motre for the same improvement in Sound if I would have spent my Money on off the shelf high end hifi.
 
Hey - have you guys in the US tried upping your line voltage to 240v?

The big deal with 240V is that you can run more power over the same wire safely. A 240V 15A circuit can carry more power than a 120V 20A circuit.

240V x 15A = 3600W
120V x 20A = 2400W

I've seen a number of amps that work with both 120V or 240V and many are rated for a lot more power when they are fed by 240V power.

Power companies run as high as 765,000 Volts for long distance transmission lines because it increases the capacity they can put on the lines.
 
The big deal with 240V is that you can run more power over the same wire safely. A 240V 15A circuit can carry more power than a 120V 20A circuit.

240V x 15A = 3600W
120V x 20A = 2400W

I've seen a number of amps that work with both 120V or 240V and many are rated for a lot more power when they are fed by 240V power.

That is assuming you can use 240 volts. A #12 solid wire can carry no more than 25 amps and #10, 30 amps so you really don't cary more power on a wire with 240 volts.
 
That is assuming you can use 240 volts. A #12 solid wire can carry no more than 25 amps and #10, 30 amps so you really don't cary more power on a wire with 240 volts.

240V at 10A is twice as much power as 120V at 10A.

So if you can double your voltage with the same or similar sized wire you can get more power across it.

You can see below from a wire sizing guide that #12 and #10 wire can carry double the wattage at 240V that they can at 120V.

120V (US) (@ 80% max load)
(50ft run or less)

Gauge Amps Watts
#16 - 9 --- 1080
#14 - 12 -- 1440
#12 - 16 -- 1920
#10 - 24 -- 2880
#8 -- 32 -- 3840
#6 -- 40 -- 4800
#4 -- 48 -- 5760

240V (US) (@ 80% max load)
(50ft run or less)
Gauge Amps Watts
#16 9 2160
#14 12 2880
#12 16 3840
#10 24 5760
#8 32 7680
#6 40 9600
#4 48 11520
 
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Maybe I am missing something here Mark and that is possible.
The only way I can achieve 240 volts is with 2 120 volt legs. One from each side of the buss bar. That along with a neutral and or a ground is the only way to get 240 volts. That is of no value for 120 volt equipment and it doesn't make possible to have more amperage, power or volts on a single wire.
 
Maybe I am missing something here Mark and that is possible.
The only way I can achieve 240 volts is with 2 120 volt legs. One from each side of the buss bar. That along with a neutral and or a ground is the only way to get 240 volts. That is of no value for 120 volt equipment and it doesn't make possible to have more amperage, power or volts on a single wire.

There are multiple issues here.

1. You need an amp that takes BOTH 240V or 120V.
For example the Emotiva XPA Gen3 operates on any line voltage between 100 VAC and 250 VAC 50/60Hz.
It is rated for more power running on 240V than it is running on 120V.

I also have a Meanwell 2kW powersupply for my chargers that is rated at 1500W at 110V and 2000W at 240V.

2. You need to be wired for 240V.
120V AC = Neutral, Line1 or 2, Ground.
240V AC = Line1, Line2, Ground
My terminology may be a bit off, but the difference is that you are getting 240V between Line1 and Line2, but only 120V between Line 1 or Line 2 and Neutral.

Line 1 = + 120V from Neutral
Line 2 = - 120V from Neutral

Line 1 and 2 have a waveform of 0-240V.
Either line 1 and Neutral or Line 2 and Neutral have a waveform of 0-120V.

I think I have that right. I'm a BSEE, but not an electrician.
 
My line of comment was based on the beginning of your post number 85.
There you say that with 240 V you can run more power over the same wire. Maybe it was just the wrong verbiage that you used. I understand and totally agree what you're saying with 240 V but a single wire can only carry so much amperage before it's not safe.
 
My line of comment was based on the beginning of your post number 85.
There you say that with 240 V you can run more power over the same wire. Maybe it was just the wrong verbiage that you used. I understand and totally agree what you're saying with 240 V but a single wire can only carry so much amperage before it's not safe.

Please keep in mind that Current is only one of the multipliers with regard to power.

So even if the current remains constant, if you can pull more voltage you are getting more power.

P = VI or Power(W) = Voltage(V) X Current(A).

So you get twice as much power over the same wire if you double the Voltage.

A wire is much more limited in Current capacity than it is in Voltage Capacity.

Current is what heats up wire. Higher voltage means with the same current means that the same number of electrons are traveling through the wire, but at a higher energy state.

If you run 240V x 20A through a 2:1 transformer you get 120V x 40A. Obviously that would be for a perfect lossless transformer, but hopefully you get the idea.

So going back to post 85, what I said was true. You can get MORE power over the same wire safely if you are running higher voltage and the same current.

Also most electronics are more efficient when running higher voltages and lower current for the exact same power.

That is one reason that I'm running 14S on my speed heli. At full charge that gives me 58.8V. My ESC is rated for 200A and my Motor is geared for 14S and is more efficient than a motor with a higher kV rating running lower voltage because I can get the same power at lower current and have less heat loss so the system runs cooler.
 
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I think that we are confusing:
wire = conductor
with
cable = two or more conductors

Most US 240V cables have 4 conductors:
Hot 1
Hot 2
Neutral
Safety Ground
 
My Parasound HCA 885A amplifier came with a standard C13 to NEMA 1-15P 18 AWG power cord. Just for testing, I ordered a 14 AWG power cord from Amazon for $10. At low volume I cannot hear the difference but once I got it to near reference level, the bass sound a little fuller and the drums seem to have a little more kick with the thicker cable.
 
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