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Regulating output wattage
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<blockquote data-quote="Water Bear" data-source="post: 8865437" data-attributes="member: 673826"><p>The math is like this: Ohm's law is P (power) = V^2 (voltage squared) / R (impedance). (This is only true under some pretty strict assumptions, namely that you can represent your speaker as an RLC circuit. Let's not worry about this too much).</p><p></p><p>Without giving a science lesson on impedance, the point is that it depends on the frequency of alternating current. Your "4 ohm nominal" speakers won't measure 4 ohms on a DMM. We're going to assume that they present a 4 Ohm impedance at least some of the time during normal operation.</p><p></p><p>Soooo...hook your DMM up to your amp's speaker outs. Solve the equation sqrt(P * R) = V. Example: For a 100 watt speaker at 4 ohm, one channel should output sqrt(100 * 4) = 20 Volts. Set your head unit volume to whatever you tune at, turn up your gain until your DMM reads 20 V AC. Boom, you're done. Your amp will produce no more than 100 watts per speaker if you don't exceed tuning volume.</p></blockquote><p></p>
[QUOTE="Water Bear, post: 8865437, member: 673826"] The math is like this: Ohm's law is P (power) = V^2 (voltage squared) / R (impedance). (This is only true under some pretty strict assumptions, namely that you can represent your speaker as an RLC circuit. Let's not worry about this too much). Without giving a science lesson on impedance, the point is that it depends on the frequency of alternating current. Your "4 ohm nominal" speakers won't measure 4 ohms on a DMM. We're going to assume that they present a 4 Ohm impedance at least some of the time during normal operation. Soooo...hook your DMM up to your amp's speaker outs. Solve the equation sqrt(P * R) = V. Example: For a 100 watt speaker at 4 ohm, one channel should output sqrt(100 * 4) = 20 Volts. Set your head unit volume to whatever you tune at, turn up your gain until your DMM reads 20 V AC. Boom, you're done. Your amp will produce no more than 100 watts per speaker if you don't exceed tuning volume. [/QUOTE]
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Regulating output wattage
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