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Do I really need the expensive cable to power a 1000 watt amp?
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You should use 2AWG or thicker.
If that's what you mean by "the expensive cable," then yes. Thicker wire is more expensive than thinner wire. And you need thick wire. Don't cheap out and buy thinner wire.
But there's no "magic" in power cable that makes one wire better than another - as long as it's of a thick enough gauge you're golden.
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>>1951615

Auto electrical systems are low voltage so if you want to run high power systems they will draw lots of current to make up for the low voltage P=VI. This requires large gauge wires to carry that current. You can try using smaller gauge wire fused at a smaller current rating but you may not be happy with the results.
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Why not use this? It works in a house
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>>1951741
This guy already explained it: >>1951643

These cables are rated for something like 32A, which is a lot of power at 110/220V but at 12V is only 384W.
Cables aren't rated for power, they're rated for current (wire gauge) and voltage (insulation thickness) separately.
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>>1951741
Do it. Take some of the wire, coil it aroind, and put a tea pot in the middle of the coil and you can boil water while you try to power your stereo.

1A @ 110V = 110W
1A @ 12V = 12W
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>>1951615
https://www.crutchfield.com/S-g251Xyq11rA/learn/learningcenter/car/cable_gauge_chart.html
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>>1951615
Now is this an actual 1000 watts like a ham radio digital rated amplifier or is it 1000 marketing music watts and the chip inside is actually only rated to 10 watts?
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>>1951615
It's only 500wrms so you could get away with 4g good quality oxygen free copper cable. It also depends on the length of the run if the battery's in the boot you may be able to use CCA without burning down your car but I wouldn't personally. I'm running 1000wrms from a monoblock and about 90wrms from a 4 channel amp I have a 3 foot run of ofc 2g going into a distribution block then less than a foot of 4g to both amps all runs fine and doesn't warm up the cables. Another thing I'll point out is make sure you have a good ground remove all paint from around where you bolt it to the chassis and make sure the ground is the same size as the positive people seem to forget they are creating a circuit and think they can skimp out on the ground.
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>>1951615
https://en.wikipedia.org/wiki/American_wire_gauge
Check the RMS wattage on your amplifier to figure out what kind of amperage you will draw. You should be able to use the chart to figure out what wire thickness you'll need. For example, I have 2 Pioneer GM8704D amps in my car. It said 1200W on the front of the box but they are 400W RMS. P=VI => I = 400W/14V = 28.6A max. From the chart I just ran 10ga from the battery to each amp. Make sure you put an inline fuse on each red cable from the battery to your amp. I've been running it as loud as my ears can handle nonstop and so far no fires, LOL. No blown fuses, either. I've seen youtube videos of guys buying "oxygen free copper cable" and other retard shit. Just your regular O'Reilly's or whatever cable is fine.
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you guys are comparing the 1000w output to the input requirements... the 1000w output is AUDIO not POWER, its not sending 1000w of electricity to the speakers. you need to see what AMPERAGE the amplifier requires and select your power wire gauge from that data. your car battery is rated in amps not watts. when you go buy a new battery its selected on the amps so your starter has enough power to crank. because the starter requires high amps.
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>>1952250
They're directly related, retard. I=P/V
>it's not sending 100w of electricity to the speakers
that's literally the definition of an amplifier. In fact, the power consumption will be a bit higher because of inefficiencies.
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>>1952315
Power consumption will be based mainly off of the RMS wattage on the amplifier. Instead of the power consumption being higher due to inefficiency, the sound output is actually lower due to inefficiency. Whatever isn't output to the speakers is expended as heat. That is why more efficient amplifiers like class D will give better/louder sound on lower wattage numbers and make a LOT less heat.
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>>1952315
>>1952611
500W RMS in "music power" doesn't equal 500W RMS for normal power like a motor or light bulb.
I'm not sure how they calculate it, but 500W RMS "music power" could only require 350-400W RMS power from your power source.
Peak wattage (1000Wp in this case) is even worse because there isn't a real set standard of rules to calculate it. SMPO(?) ratings can be in the 10's of thousands of watts because the amplifier doesn't even have to survive the output pulse.
Audio power when going to a speaker can't be measured the same way as normal loads. If you were to send a 60Hz sine wave to the amp as the input, and use a massive resistor on the output as a load (2 Ohms can pull 500W "music power" for this amp), Then you can start using Ohms Law to calculate the "standard" output power with an AC voltmeter. Like wise if you do that setup, then you can measure the input DC voltage/current to calculate the efficiency.

Audio systems are fucking terrible.
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>>1952631
Why don't you show me on an amplifier's packaging where they list the input power requirements? Obviously they don't you fucking retard. However, they do list the RMS wattage and if you wire the amp for that then you won't have any fires. What is there to figure out, you fucking sperg?
>Audio systems are fucking terrible.
The OP just wants to wire up his amp and you go off on this "I'm smarter than everybody else" tirade when you're obviously too dumb for basic reading comprehension. Bend over and fuck your own face.
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>its not rocket science

The formulas for calculating current draw
To determine the approximate current draw (in amperes) of your amplifier, you must first calculate the total power of the system. Multiply the number of channels by the number of RMS watts per channel. If you have multiple amps, add up the total RMS power figures to arrive at a grand total.

Generally speaking, there are two kinds of amplifiers — Class D and Class AB — so there are two formulas for calculating current draw. (You can read the detailed explanation below the chart.) You use the formula that applies to your amplifier. If you don't know what Class your amplifier is, use the Class AB calculations for the safest result.

Class D amplifier: total RMS Wattage divided by 0.75 Amp Efficiency divided by 13.8 Volts equals Current Draw in Amperes

Class AB amplifier: total RMS Wattage divided by 0.50 Amp Efficiency divided by 13.8 Volts equals Current Draw in Amperes

The resulting figure is your system's approximate maximum current draw, whichever kind of amplifier you have. Compare this number to the numbers in the "Amperes" column in the chart below. Now figure out the cable length you'll need — that's the distance from your battery to the amplifier's mounting location. Cross-reference these two figures in the chart to determine which gauge of cable you need.
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>>1952650
Any decent amp has built-in fuses that any retard like you can count, so there is your input requirement. There is also a saying "RTFM" which can also list requirements.
Not to mention I wasn't replying to the OP, I was replying to two other anons.
Sorry you are intimidated by knowledge.
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>>1952689
>built-in fuses
Those protect the equipment, sperg, not the wire.
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>>1952672
Oh hey look, it's the same as the battery fuse rating of the amp
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the average bait thread succeeds again
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25
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>>1952689
Like >>1952711 said, that's to protect the equipment internally. You fucking retard, anytime you wire an amp you need to put YOUR OWN INLINE FUSE on the positive end to prevent electrical fires. I shouldn't have to yell but you are so obviously retarded and handing out retarded advice I have to shout it out. "RTFM" doesn't tell you anything about input current requirements, it only tells you how to wire it up, what buttons/dials are for, etc. You've obviously never read one of these yourself.
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>>1952672
You're not supposed to divide the RMS wattage by efficiency to find the current draw. The current draw is calculated straight from the RMS wattage. The efficiency tells you how much energy is sound vs. dissipated heat.
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Just look at the fuse on the amp and get wire big enough for that.

Its probably a 40 amp or two 20 amp fuses. Get wire rated for that at 12 volts. Go buy a decent set of 4 gauge jumper cables that are long enough and use that for power and ground.
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>>1953093
>The current draw is calculated straight from the RMS wattage.

Not for an audio amplifier. RMS power ratings for AC/DC voltage is not the same as RMS "music power" from an amp/speaker setup.
No, I'm not talking about peak vs rms output, audio systems have their own power calculation method.
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>>1952711
>>1953091
No shit those fuses protect the equipment. I never said anything about NOT putting additional fuses on the V+ line. Why are you coming at me with that shit?
If you have a 40A fuse on the amp, then guess what? You won't be constantly pulling over 40A into the amp. From there, you can figure out what gauge wire you'll need to carry the 40A to the amp.
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>>1952250
lmao
please explain now 1000 watts of audio is different from 1000 watts of ‘power’
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>>1951615
just run a 4 gauge wire u lazy
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>>1953093
You need to consider the efficiency because you want to supply enough to power the amp.
The amp needs power for itself and the rms rating of the speakers is what is passed through.
If your speakers that have a rating of 100W rms together and the amp has an efficiency of 50% the amp will draw up to 200W.

The wires can always be bigger.
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>>1951615
Yes and yes. 1000/12v = amps.
So 83amps. You can us 4 20amp cables. Or 2 40amp cables. Quality doesn't matter but max amp rating does.
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>>1953361
>please explain now 1000 watts of audio is different from 1000 watts of ‘power’
>>1953698
>1000/12v = amps. So 83amps.

>https://www.kicker.com/app/misc/support/tech/tech_papers/docs/PeakVsRMS.pdf

Power used to supply anything with voltage/current is measured at a constant frequency (i.e. 60Hz from a wall outlet). Audio is a variable frequency and amplitude. The calculations are not the same.
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>>1952250

>>1952631
>>1952672
Theoretically based
However one should factor in the chinesium factor on consumer audio equipment all watts above about 10 are just mentioned on the packaging for orange teens with stickers on their baseball caps to brag about. For any numbers above 500 you get a free monster energy sticker.
>>1952689
Practically based. Best way to go
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>>1953361
>please explain now 1000 watts of audio is different from 1000 watts of ‘power’

ok. here goes: you are an idiot. google and learn something
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>>1953837
>>1954214
You are both retarded schizos. Why is it fused then exactly at 1000w/12v? I’m not replying to you dumbasses again
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>>1951637
>there’s no “magic” in power cable that makes one wire better than another
the majority of cheapshit car audio power wire is copper clad aluminum rather than 100% copper, which definitely makes a difference.
OP, after you’ve used the amperage of the case fuses to calculate the power needs of the amplifier (although you should use 14v instead of 12v as that is closer to the actual operating voltage of your vehicle) and not whatever inflated retard number they have written on the box you can determine what gauge you need. If it’s actually a 500w amp, 8 gauge copper is fine. If it’s really 1000W then you’ll need 4 gauge. If you’re using shit tier CCA wire, first of all don’t, but otherwise bump up the gauge to compensate for the shitty conductor you chose or use a shorter wire run to mitigate the voltage drop.
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>>1954334
>Why is it fused then exactly at 1000w/12v? I’m not replying to you dumbasses again

thats because you know you are wrong. and have nothing else to offer to prove otherwise. now, kindly go learn how amps watts and volts work together and how you calculate one to another.
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>>1951615
Depends on your definition of expensive and whether or not you want to start a fire.
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>>1952819
Yeah legit, you need to size wire for the fucking fuse. Morons.
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Power ratings for commercial sound stuff is fucking bullshit and no one, not even the manufacturer knows how that shit is calculated.
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>>1953837
1000 watt is 1000 watt you idiot.

"audio watts" is just marketing bullshit
Take up a physics book instead of the marketing bullshit stories and you'll realize how Ohms law, Kirchhoff, DC, AC and RMS are all about the same thing.
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>>1954378
No it doesn't. CCA is fine for car audio. It's fine for most applications.
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>>1956899
Except watt on advertisements for audio equipment is not.
Advertisement is key here, not audio.
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Only poor fags use cca. Get some ofc from skyhigh. Welding cable is a better option than cca as well.
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>>1957290
Yes but that dude who knows just enough to not understand it keeps using it as if it is a real thing.
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Owner of car audio business for 14+ years here. 1 watt is an exact amount of energy, and it does not magically change when used for audio purposes. 1 watt is 1 watt. Anyone disagreeing to the basic physics of voltage, power and resistance (and the relation between them) needs to go back to school.

Thicker wire = less voltage drop, particularly at high amperes. When running e.g. 1,000 watts through a 12V system, a thinner cable will increase resistance compared to a thicker one causing two things:
1) Voltage drop (bad for amplifier output)
2) Heat (bad for the wire because the plastic insulation will melt, the copper will touch ground - yes, it will because Murphy's law - and then your car burns up.)

The fuse you ALWAYS install as close as possible to the battery on your typical 2-4ga wire in a car audio system is there to do 1 thing, and 1 thing only: make sure the cable does not exceed the amperes it can handle (which VARIES with cable length!). It is not there to protect the amplifier, the speakers or your mother-in-law. It protects the cable, keeping it from overheating (yes, sure, it also protects from short-circuiting but a short circuit leads to heat so you get my drift).

The more expensive cable types typically feature 99,9999+% oxygen free copper which we tell you is important, but you will never hear the difference from a cheaper cable.

We also tell you that you need as many thinner strands as possible in the cable, because electrons tend to travel along the outer skin of each strand as opposed to the strand center. This is called skin effect in the industry. But again, you will never be able to tell the difference.

OFC wire with a gazillion strands costs a lot of money, but your average hoonigan with a couple of 12 inch woofers in the trunk will do fine with cheaper cable AS LONG AS IT'S THICK ENOUGH.

Tldr; Read your amplifier's manual for recommended fuse size. Find length of cable. Look up a 12V wiring table and find correct gauge. Buy cable.
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>>1957537
Anon, has the audio industry gotten better they used to sell 800 (microscopic text: peak) watt home systems that were actually 4x25w
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>>1957537
Me again. Get the same gauge cable for your ground/negative wire as well.

If I had a dollar for every knobhead who thought they could use thinner ground wire because they thought the power had been "used up" in the amplifier - negating the need for a negative wire as thick as the positive one - I'd be a very rich man now.
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>>1957537
100% agree on everything you said except the skin effect. The skin effect is an AC thingy and does not matter for anything under a few megahertz.
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To recap:
>retard thinks 1000 watts is different from 1000 ‘audio watts’
>anons check equipment documentation
>says to use 80a fuse

Hopefully we can purge these people from society one day
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>>1957542
If people are that dumb they deserve to have their car burn down before their eyes
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>>1957560
>Hopefully we can purge these people from society one day
that would be a beautiful day
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>>1957540
Good brands tend to be more honest about their actual output. Chinesium brands will write 1,500W SuperMaxPower on the amplifier housing right next to the integrated 15A fuse.

I used Italian Audison amplifiers for a few years due to their sound quality (but like an Alfa Romeo, they spent a lot of time being repaired). They had a very good mono amplifier that was rated at 900W by the manufacturer, but exceeded 1,000W true output to the woofer in independent tests.

Power outout also depends on speaker resistance. All car audio amplifiers are generally rated at 4 ohm, which is what your typical speaker operates at. But some amplifiers are rated for use at 2 ohms (or even 1 ohm, like the mono amp I mentioned). So you may end up buying an amplifier that says 2x200W on the box, but the fine print mentions that this is their 2 ohm rating. So when you're using it with 4 ohm speakers, you'll typically only see half of that, i.e. 2x100W (roughly).

Another trick used by chinesium manufacturers is to not mention in how much distortion they allow at any given rating, or they use lingo such as "1,000W at 10%THD". Problem is, THD means Total Harmonic Distortion. And when you have 10% distortion, your music doesn't sound lile music anymore.

What happens when you crank the shit out of the "gain control" on the amplifier (IT IS NOT A VOLUME KNOB FFS) is that above a certain treshold, you get a lot of distortion.

If you look at that signal using an oscilloscope, you'll see squares instead of sine waves. We call that "square pulse signal", and when you feed that to a speaker the voice coil tends to melt, seize and stop moving up and down the axis of the speaker magnet (effectively destroying the speaker).

As long as you have a powerful, quality amp that doesn't feed square pulses through the speaker wires, you'd be amazed at how large stroke a speaker cone can have without being damaged.

More true amplifier power = more control of the speaker element.
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>>1957559
It's been an established truth in the car audio industry for decades, but I always suspected it was something the corporations told us (the dealers) to sell more expensive cable to Average Joe customers.

I'll look up what you said for my own future reference, but I have no reason to doubt you. Thanks for the info.
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>>1957563
Cant disagree with you on that one haha :-)
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>>1957576
your simplest reference would be wikipedia, I just checked and there is even a table with some examples.

The skin effect is also being pushed in the "audiophile" crowd for speaker cables and such since you actually see some AC there. But even at those frequencies it simply doesn't really matter because even if you use an old extension cord as speaker cable the strands will be thinner than required.

These people love to abuse these terms because they are -just - complex enough to be beyond most people's understanding so they can bullshit about it freely.

P.S. from what I've seen you know your shit, I like that.
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>>1957719
Yeah we get that from speaker wire sales reps all the time. But I kind of understand them... like me, they're just sales guys who don't have electrical engineering backgrounds and have to trust what the corporation is teaching them.

I come from a marketing background myself (many moons ago....), but have worked on cars my whole life. So I have a lot of experience with lower voltage systems, but essentially everything I know about electric and electronic stuff is self-taught, based on extensive hands-on experience (about 25 years worth).

Somewhere along the road I got smart enough to realize I don't know all the answers, so I need to learn from people who are more knowledgable than I am. Little by little I became somewhat proficient by asking dumb questions to smart people.

These days, most of the time I wish I'd become an electrician instead of getting a college marketing degree. It's fun and you can do/make/repair all sorts of things once you have the basics down. But I'm a semi-old fart now and it's kinda late in life to attend trade school....

Thanks for the kind words anyway, I appreciate it.
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>>1957719
>even if you use an old extension cord as speaker cable the strands will be thinner than required.

That's not how skin effect works. Stranded cable acts the same as solid cable as far as skin effect goes. The only way to get around this is to use cable with many individually-stranded conductors, also known as Litz wire.

Don't get me wrong, it doesn't really matter for audio cables, but the more you know...
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>>1951615
They used to build those two blocks from where I went to school. As we got older we would dumpster dive and pull out all kinds of mostly good equipment to rebuild. It was an awesome racket in high-school.
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>>1957997
Ah sorry that may have been lost in translation. It was meant as a figure of speech like any crappy cable will be good enough, but I see now that it could easily be interpreted wrong



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