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<blockquote data-quote="highfigh" data-source="post: 8895318" data-attributes="member: 691685">Power supply is everything when amplifiers are concerned and if it can provide 75W with 12.5VDC or 14.4VDC, it means the power supply has more/larger capacitors than an amp which can&#039;t provide equal output at different supply voltage but the speaker impedance you&#039;re providing isn&#039;t on their chart, which is the reason I recommended contacting JL.As the impedance drops, the Current through the output devices increases, their temperature increases and if they and their heat sinks can&#039;t shed this heat, they cook. Power is a calculated value and Voltage, Current &amp; Resistance can be used to derive this and other values, depending on what is known. Since 75W is known, Current (I) can be derived by using any resistance (pure resistance, since Impedance is the resistance at specific frequencies). The current @75W increases drastically as the resistance goes down, so for 4 Ohms, 2 Ohms and 1.33 Ohms:square root of 75 W/4 Ohms= 4.33A............................75W/2 Ohms = 6.12A............................75W/2 Ohms = 7.51AIf the outputs can handle it, maybe it&#039;s fine, but I would check with JL and find out if you can minimize any harm by adding a cap to each midbass and a coil to the woofers.The diagram may help-[ATTACH=full]64389[/ATTACH]</blockquote>

[QUOTE="highfigh, post: 8895318, member: 691685"] Power supply is everything when amplifiers are concerned and if it can provide 75W with 12.5VDC or 14.4VDC, it means the power supply has more/larger capacitors than an amp which can't provide equal output at different supply voltage but the speaker impedance you're providing isn't on their chart, which is the reason I recommended contacting JL. As the impedance drops, the Current through the output devices increases, their temperature increases and if they and their heat sinks can't shed this heat, they cook. Power is a calculated value and Voltage, Current & Resistance can be used to derive this and other values, depending on what is known. Since 75W is known, Current (I) can be derived by using any resistance (pure resistance, since Impedance is the resistance at specific frequencies). The current @75W increases drastically as the resistance goes down, so for 4 Ohms, 2 Ohms and 1.33 Ohms: square root of 75 W/4 Ohms= 4.33A ............................75W/2 Ohms = 6.12A ............................75W/2 Ohms = 7.51A If the outputs can handle it, maybe it's fine, but I would check with JL and find out if you can minimize any harm by adding a cap to each midbass and a coil to the woofers. The diagram may help- [ATTACH type="full" width="201px"]64389[/ATTACH] [/QUOTE]

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