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what are OHM's and RMS'?

Old 09-04-2002, 04:36 PM
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Default what are OHM's and RMS'?

just wondering.. i never knew what they were.. or stand for
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Old 09-04-2002, 04:59 PM
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ohms doesn't stand for anything. it is the measurement of the resistance an object has to current flow. like a meter is a way to measure distance. 1 ohm of resistance connected to a 1 volt power supply will have 1 Amp of current flowing threw the device.
RMS stands for root means square. It is what you should look at when you are buying amps and speakers. I believe it is .707 x peak power?
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Old 09-04-2002, 05:07 PM
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well said...^

let me put it in words i understand....:D

when dealing with car audio....OHM is a rating on the speakers, per voice coil. and on the amp, the amp gives out different amounts of power at different OHM. the lower the OHM, the more power it can give off. but some amps wont play at too low of an impedance (OHM) because it will cause them to run really hot.

so what you will have to do when looking at sub and amp combos, is the impedance of the sub, and the what impedance does the amp give the most power. if they

RMS.....thats the power rating of the speaker. peak doesnt mean much...RMS is a number to look at.
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Old 09-06-2002, 03:25 AM
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RMS (root mean square) can be calculated using the .707 x Peak Power method. its not exactly accurate but for car audio purposes its just fine.
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