Okay im confused about power ratings...

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Machspeed

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Lets just say i have a 500w rms 1000w max sub. To fully amp it wont i need a 500w rms amp with a 1000w max power rating, or will i need a 1000w max rms amp? I was taught the first way...whatever the sub is rms thats what its going to run at no matter what, unless you cant give it enough rms power cuz the amps max power isnt high enough.
 

underdog1924

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Peak wattage and RMS wattage are two completely different things. Peak is short bursts of power, while RMS is continuous power. Peak power really doesn't mean a whole lot. Just pay attention to the rms values. Again the sub only accepts the power the amp gives. The power rating on the sub is what it can safely run up to without having problems. Some subs though can be over or under rated. I believe your Audiobahn can take more than it's rated at. If it's rated at 500 watts rms I would go with the JBL 600.1.
 

SHO92

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Like was said before, the sub will take what its given by the amp, not the sub taking 500watts from a 200 watt amp. So you are right about a 500 watt rms sub using a 500 watt rms amp to get the max power. It will handle up to 1000 watts for a brief period. But if you give a 500watt rms sub 700 rms watts, thats what its gonna run at. It can't regulate the power, thats done by the amp.
 

LOUDSHO92

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You need to match the max amp rating to the sub max rating. If you go over the max sub rating chances are you will blow it. If you go over the max RMS of the sub you probably will not blow it.
 

Dave Ladely

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RMS watts is NOT what an amp "runs" at, it is the maximum watts it is designed to take. Peak watt is merely a doubling of rms watts and means nothing whatsoever, it is ******** marketing that some say it means instantaneous power for maybe a few milliseconds. It has no real value as an electronic specification, just marketing.
I really don't get how someone can get theory construed that a speaker is designed to run at a certain power. A 500 watt speaker is best run at significantly less than 500 watts rms, just as a car engine which redlines at 7000 rpm max is NOT designed to run at 7000 rpm, but is much happier at less than that. A speaker is less and less happier the more watts, the less watts is best and runs coolest.
 

yamahaSHO

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Dave Ladely:
RMS watts is NOT what an amp "runs" at, it is the maximum watts it is designed to take. Peak watt is merely a doubling of rms watts and means nothing whatsoever, it is ******** marketing that some say it means instantaneous power for maybe a few milliseconds. It has no real value as an electronic specification, just marketing.
I really don't get how someone can get theory construed that a speaker is designed to run at a certain power. A 500 watt speaker is best run at significantly less than 500 watts rms, just as a car engine which redlines at 7000 rpm max is NOT designed to run at 7000 rpm, but is much happier at less than that. A speaker is less and less happier the more watts, the less watts is best and runs coolest.
Peak is not always a doubling of RMS. Off the top of my head I can not think of the equation, I should know though cause thats my job. Everyone here is right, do not worry about peak values the Root Means Squared is what you are concerned with. You can match a 700 watt rms amp with a 500rms sub, just don't turn it up all the way. RMS is what it is capable of pushing constantly. I ran a JBL BP1200.1 to 2 Vega 12"s The subs handled 400rms and 800 peak each. I matched an amp that pushed 600watts rms to each, I had no problems. In fact, by matching a more powerful amp you will more than likely have cleaner sound at higher levels because the amp is not "struggling". Also Like I have seen so many people do, don't mount an amp upside down. This does not allow the amp to cool properly which can cause distortion and clipping.
 

Dave Ladely

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Peak power IS merely a doubling of RMS, it has no electronic meaning, it is totally marketing.
"IHF Music Power" rating does have a slight bit of rational meaning, and it is 1.4 times the RMS rating. Check it out.
 

Dave Ladely

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Yes, I too, have hooked up high power amps up to speakers of supposedly lower power "ceiling". Like, I hooked a 1000 watt Phase Linear home amp to a speaker rated at 200 watts with no problem. Its not so much music that blows speakers, but distortion, and a high power amp will work with less distortion at higher volume levels. I've been considering using my 2,500 watt DC to AC inverter with a good home (110v) 5 channel amp in my car. Home amps are superior to car amps, so should work well. Before you freak out, do some thinking about it, OK? I was the person who started the super amp revolution in 1968, so I do like power. Ask my old friend Bob Carver, founder of Phase Linear, Carver Corp, and now Sunfire.
 

SHOZ123

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I've worked with pro sound equipment for 25 years and the only times I've had problems with speakers is if the amp input was too high or the amp was under powered, both causing extreme distortion.

I have no problem pumping 1400 watts into 300 watt speakers.

<small>[ December 10, 2002, 04:06 AM: Message edited by: SHOZ123 ]</small>
 

Ian Macoomb

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This is going to be a long one.

Power ratings of speakers are full of it. Some companies lie more than others. There aren't many that tell the truth. JL Audio is one speaker company that I'd trust. They rate their speakers by how much power they can take continuously for a certain period of time (like 8 hours of sine wave, single tone, rated power). At least that's the way the used to rate them. I've been out of the car stereo scene for a few years so I'm not sure if they still rate them the same way.

Anyway, for most respectable companies you can match the amp power to the speaker rating but that is not a must. You can under power a speaker as much as you want. Likewise you can over power a speaker as long as you are careful. Watch out for distortion and if you hear it turn it down. It's pretty simple.

That said, this doesn't mean that distortion will **** a speaker. If the speaker is distorting because it being overpowered then this is true. However a say, 100 watt speaker, will never be hurt by a 10 watt amplifier no matter how bad the amp is distorting. Why would it? The only thing that can hurt a speaker is over excursion or overheating (and physical damage). You aren't going to overheat or overexcurt (is that a word?) a speaker by overpowering it.

Now this is some radical thinking to most. I'm not going to debate it here. If you want to debate that fact take it elsewhere. The newsgroup rec.audio.car and the forums at www.carsound.com are the best place for intelligent debate. I've spent a lot of time there and that's what I've learned over the years from the experts there.

Now about the max power being twice the "RMS" power, this is true. The power output of a square wave is double that of a pure sine wave. Usually an amp is limited by the voltage of the voltage rails. It can't produce a voltage higher than that. If you are producing square waves you can produce twice as much power as you could with the same amp producing a pure sine wave.
 

yamahaSHO

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Dave Ladely:
Peak power IS merely a doubling of RMS, it has no electronic meaning, it is totally marketing.
"IHF Music Power" rating does have a slight bit of rational meaning, and it is 1.4 times the RMS rating. Check it out.
Peak power is not merlely doubling of RMS. Let me find my notes from tech school(principles of electronic) I will give you the formula.
 

Ian Macoomb

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yamahaSHO:
Dave Ladely:
Peak power IS merely a doubling of RMS, it has no electronic meaning, it is totally marketing.
"IHF Music Power" rating does have a slight bit of rational meaning, and it is 1.4 times the RMS rating. Check it out.
Peak power is not merlely doubling of RMS. Let me find my notes from tech school(principles of electronic) I will give you the formula.
Peak power of a sine wave is twice the average power.

Here's proof:

You know that the RMS voltage of a sine wave is the peak value time root 2. You also know that power is IR, I^2R, or V^2/R.

Take the last formula and use Vpeak*root2 for V. V^2 = (Vpeak*root2)*(Vpeak*root2) or Vpeak^2*2.

The power therefore is 2*Vpeak/R.
 

RStalveyARFF

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Dave Ladely:
Yes, I too, have hooked up high power amps up to speakers of supposedly lower power "ceiling". Like, I hooked a 1000 watt Phase Linear home amp to a speaker rated at 200 watts with no problem. Its not so much music that blows speakers, but distortion, and a high power amp will work with less distortion at higher volume levels. I've been considering using my 2,500 watt DC to AC inverter with a good home (110v) 5 channel amp in my car. Home amps are superior to car amps, so should work well. Before you freak out, do some thinking about it, OK? I was the person who started the super amp revolution in 1968, so I do like power. Ask my old friend Bob Carver, founder of Phase Linear, Carver Corp, and now Sunfire.
Oh god, next he's going to say he invented the internet!!! oh_my
 

Machspeed

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[/QUOTE]Oh god, next he's going to say he invented the internet!!! oh_my [/QB][/QUOTE]

:rolleyes: No that was me...I did it in 1995. I was just bored and lookin for something to do. If i had any idea it was gonna go anywhere i wouldve patent it...stupid aol :mad:
 

krupt89

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A good sub is very hard to blow by slightly over powering it. If ur running a 400 watt rms and 900watt max sub at 900 watts and u dont beat the **** out of ur stereo ull be fine. Yet it is very easy to blow a sub from underpowering it because it is desighned to run w/ a certin amount of watts running to it. Thats like running a pro street motor thats designed for high octane on low grade pump gas. How would it run? And wut would happen to the motor after time and time again not putting the proper fuel in it? Thats how it is w/ a sub. But i also do not like to run my subs at peak power. I have 2 sony xplod subs rated at 900 watts peak and 400 rms w/ an xplod 1200 watt amp turn all the up running them and the only problems i have had is the oputs in the amp fryin but ive heard that this is comon w/ all xplod amps.

<small>[ December 16, 2002, 01:25 PM: Message edited by: krupt89 ]</small>
 

SHOZ123

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On my Pro PA I put 900+ watts into 300w 18" speakers all the time. It is not the power but the distortion that kills the speaker.
 

Ian Macoomb

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Guys, distortion will only hurt a speaker if the distortion is coming from the speaker. If the amp alone is the cause for the distortion the speaker will not be harmed. It can't. How could it? It takes heat or excessive excursion to hurt a speaker. If you're no where near a speaker's power handling you aren't going to hurt it. Simple as that.

And there's no such thing as underpowering a speaker. What do you think you are doing when the volume is at minimum? Do you really think that a 300 watt amp only puts out 300 watts and do you think that if you only feed it 100 watts it's going to die?

IT's a MYTH!!
 

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