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Wattage and Ohm question 


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 Post subject: Wattage and Ohm question
Posted: Wed Jan 20, 2016 11:47 pm 
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Stupid question but I can't work out how to determine the total amount of ohms in a sub and amp system.

An amp wired at 2ohm to a dvc 4 ohm sub, so which value do I use? I understand 700w at 2ohm will be 350w at 4ohm and all the rest. But how much power from an amp delivering 700w at 2ohm will make it to a 4ohm dvc sub?

 Post subject: Re: Wattage and Ohm question
Posted: Thu Jan 21, 2016 12:03 am 
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Sound is an AC waveform... As such AC principals apply... The coil will have an inductance and a capacitance (stuff all capacitance)... Inductance and capacitance will add together to give reactance and it adds to the resistance to give a total impedance for the circuit (sounds hard but it's simple formulae to work out...)

You cannot just assume anything about the power level output... As even if you work out the speaker's impedance the output is not linear and you cannot apply a direct division scale to it... You'd have to contact the amplifier manufacturer and they should have test reports for each style they sell with ball park values...

Your sub as 2x 4ohm voice coils yeah? If you wire the coils in series... Ie in one, out of it into the other and then out of it to the amp you'll get 8ohms loading on the amp (4+4=8)...

If you wire the 4 ohm coils in parallel you'll get 2ohms loading on the amp (((4^-1)+(4^-1)) ^-1) which is you add the reciprocals of the impedances and then take the reciprocal of that...

So you can place 2ohms total loading on your amp... Amp's are designed to run a certain impedance for peak performance (not just peak power)... You'd do best to match that impedance...

Again to answer your question about that amp at 4ohms you'd need to contact the manufacturer for info...




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