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Discussion Starter · #1 ·
can I measure volts and ohms at frequencies and figure out how much power I'm sending my speakers?


well I measured my subs ohms at 50hz and power source's Volts at 50hz. I got 8.7 ohms and 20volts. which is around 45watts following the formula

V^2/ohms = watts

I also measured my mids at 1000hz and got 2.6ohms and 3.35 Volts for power. which is 4.3 watts.

is this accurate?
 

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I think the test tone needs to be a sine wave at the certain frequency in order to get the correct voltage. I know you can set your gains using sine waves and known wattages to find your input/ouput voltages.
 

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Discussion Starter · #3 ·
yea the voltage I got was stable with the sine wave I used. I tested a few waves....all came at around the same voltage.

I'm not sure if the ohms I read from the speaker is accurate. I think it is.
 

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I usually measure current through the speaker, then voltage and multiply the two to get power. But what you're doing is accurate. Much less power being used than you thought?
 

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Discussion Starter · #5 · (Edited)
yeap yeap.... :) ......thats a good thing. 5 watts to the speakers and I'm good.
even 8ohm speakers judging from the effiency at 2.8V will do good with a few Volts of power.


btw....do you ever just use your HU with comps and such?.


btw...again...remember when I gave my opinion on my MB quart comps....well I recently found out one of my mids was messed up. So the review was off a bit, well that is if I was using the messed up mid...I was only using one....not sure which though.
 

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it's amazing what u can do with so little power. people think they need 200 watts on their midbass. why i dont know. my CA18's are getting just under 17 watts and they get quite loud on that little amount of power. with gains all the way down too i might add.
 
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