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Car Audio Do you live in your car? Then you need to be able to listen to some high-quality music.
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Old 08-27-2005, 12:10 AM
nlghtcrawler nlghtcrawler is offline
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I hate to ask this

i know there might be some stuff on the forum about this, but when i read about it i dont quite understand it:
what does RMS mean and what does OHMS mean? i hate to ask this guys, but i guess its important, and i was hoping some of you guys can take a few mins of your day to try and explain this to me.

THX
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Old 08-27-2005, 12:51 AM
nlghtcrawler nlghtcrawler is offline
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Re: I hate to ask this

also, if your amp dosnt tell u this stuff, how do you test ur amp for watts and stuff?
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Old 08-27-2005, 01:28 AM
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ToyTundra ToyTundra is offline
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Re: I hate to ask this

www.bcae1.com will explain it

page 7: resistance
page 8: Ohm

An ohm is a unit of resistance.

RMS stands for Root Mean Square. It's a way to rate the "average" or "musical" or "constant" power an amp can put out.
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Old 08-27-2005, 01:39 AM
Stealth_SUX_ Stealth_SUX_ is offline
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Re: I hate to ask this

Quote:
Originally Posted by nlghtcrawler
i know there might be some stuff on the forum about this, but when i read about it i dont quite understand it:
what does RMS mean and what does OHMS mean? i hate to ask this guys, but i guess its important, and i was hoping some of you guys can take a few mins of your day to try and explain this to me.

THX
I hope ur not trying to put a system together by urself, cause not to be mean though, u shouldn't even touch an amp with your knowledge. The ways to test things like ohms and shit, u need a volt meter that reads ohms. Also rms should be on the package of the amp and good amps should come with a sheet that tells accual rms.
So if u bought an amp and it doesn't say anything, u got ripped off, cause they would say 1200 max and that amp probully puts out 100 watts max. have fun, recommend u let a professional do ur car, unless u want to waste ur money
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Old 08-27-2005, 09:18 AM
nlghtcrawler nlghtcrawler is offline
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Re: I hate to ask this

its a amp i got for 10 bux... thats why i asked
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Old 08-27-2005, 12:14 PM
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CBFryman CBFryman is offline
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Re: I hate to ask this

you would have to have a n experence electrition look at the schematics of the amp to determian a safe laod for it or ask some people who have owned that amp.
1ohm Provides the resistance for 1v to only flow 1ampere. which will result in 1w. 1v is the equivelant of 1 joule. 1a is the equivilent of 1 couloumb (sp) per second of electrons. if you have 1 joule of energy doing the work of 1 coulobm per second then you have 2 things, work done, and the time this work was done. this calulates to find wattage, ie power.
a load uses up power in a circut, well actually it gives a total load which will result in a final voltage loss untill you reach 0v. so if your coil is 4ohm and you have 4v of amp output then you will flow 1 amp resulting ing 4w, you used all 4v to make this 4w.
If you have 2 4ohm coils in series and 4v then each coil uses 2v and only flows 0.5ampers and each coil receives 1w and you have a total load of 8ohm.
if you have 2 4ohm coils in parallel and 4v eachcoil still uses 2v but beause the resistance is split equally you flow 2amps and each coil receives 4w and you have a 2ohm load...
that is a run over, check out BCAE1 and it will all make sence.
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Old 08-27-2005, 01:21 PM
L|_|da L|_|da is offline
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Re: I hate to ask this

damn cb, you memorize all that?
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Old 08-27-2005, 06:48 PM
PaulD PaulD is offline
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sounds like someone swallowed a dictionary

In every days words ...... watts is power, the abilty to do work - like moving a speaker back and forth. RMS (root mean square) is "average" power. It's actually turns out to be 70.7% of max power, that's the sine of a 45 degree angle (1/2 of the full 90 degree peak). It's a way of comparing apples to apples if you use watts RMS to compare power.

Ohms is a measure of resistance, only it affects the power opposite than most would think. When you have a 4 ohm lload on an amp that is rated for 50 watts RMS @ 4 ohms, it will generally put out around 50 watts RMS when driven to full output.... just what you would expect. If you put a 2 ohm load on that same amp, the amp would put out appx 100 watts RMS. An 8 ohm load would limit the amp to appx 25 watts RMS. Remember that ohms are a resistance, the higher the resistance the more it takes of an amp to have the same power rating. An example would be ..... If I gave you a 40 lb weight, you could lift a certain number of times at a high speed - if I gave you a 20 lb weight, you could lift that one many more times at that same speed - if gave you an 80 lb weight, you would have a much harder time than with either of the first two weights. Hope it makes a little more sense.
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