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<blockquote data-quote="DanWiggins" data-source="post: 2315041" data-attributes="member: 544847">In actuality, the situation may be worsened by using thinner gauge wire!Wire has a resistance per foot rating, based upon the diameter of the wire.&nbsp; Larger diameter, less resistance.&nbsp; A 1/0AWG wire is ~2.2 times larger in area than a 4AWG wire, so you have roughly 2.2 times HIGHER resistance with your 4AWG wire.Now, why does this matter?&nbsp; Well, let&#039;s say you have a 1200W amp putting out the full 1200W output.&nbsp; At 12V (to keep the numbers easy - I&#039;m lazy...//content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif) that would be 100A (P=I*V, I=P/V = 1200/12).&nbsp; So we have 100A of current...Now, 4AWG wire has a resistance of 0.24 Ohms per 1000 feet; let&#039;s say your power run is (again, to be lazy) 20 feet.&nbsp; So we have (0.24/1000*20) 4.8 mOhms of resistance.&nbsp; With 100A running down that, we would lose (0.0048 * 100) 0.48V, or about 0.5V DC drop for your amp.What about 1/0AWG wire?&nbsp; Well the resistance is 0.096 Ohms per 100 feet, so we have a total drop of 0.2V DC drop to your amp.That&#039;s not a big difference, but it does mean you amp may not be able to fully generate all the output before clipping (the power rails will sag further), and your amp will run a bit harder (longer ON portion of the power supply&#039;s duty cycle) to compensate.&nbsp; Both of which don&#039;t help.Add another amp to the equation, so you&#039;re pulling even more current, and things get worse...Is it a fatal flaw?&nbsp; Nope.&nbsp; But something to think about.&nbsp; In&nbsp; your particular case, 4AWG is probably OK.&nbsp; Don&#039;t go smaller, though...Note too that just because your voltage sags so that you could generate &quot;only&quot; 1000W unclipped, that still means that with hard clipping you can still put out nearly 2000W of power!Dan WigginsAdire Audio®</blockquote>

[QUOTE="DanWiggins, post: 2315041, member: 544847"] In actuality, the situation may be worsened by using thinner gauge wire! Wire has a resistance per foot rating, based upon the diameter of the wire. Larger diameter, less resistance. A 1/0AWG wire is ~2.2 times larger in area than a 4AWG wire, so you have roughly 2.2 times HIGHER resistance with your 4AWG wire. Now, why does this matter? Well, let's say you have a 1200W amp putting out the full 1200W output. At 12V (to keep the numbers easy - I'm lazy...[IMG]//content.invisioncic.com/y282845/emoticons/smile.gif.1ebc41e1811405b213edfc4622c41e27.gif[/IMG]) that would be 100A (P=I*V, I=P/V = 1200/12). So we have 100A of current... Now, 4AWG wire has a resistance of 0.24 Ohms per 1000 feet; let's say your power run is (again, to be lazy) 20 feet. So we have (0.24/1000*20) 4.8 mOhms of resistance. With 100A running down that, we would lose (0.0048 * 100) 0.48V, or about 0.5V DC drop for your amp. What about 1/0AWG wire? Well the resistance is 0.096 Ohms per 100 feet, so we have a total drop of 0.2V DC drop to your amp. That's not a big difference, but it does mean you amp may not be able to fully generate all the output before clipping (the power rails will sag further), and your amp will run a bit harder (longer ON portion of the power supply's duty cycle) to compensate. Both of which don't help. Add another amp to the equation, so you're pulling even more current, and things get worse... Is it a fatal flaw? Nope. But something to think about. In your particular case, 4AWG is probably OK. Don't go smaller, though... Note too that just because your voltage sags so that you could generate "only" 1000W unclipped, that still means that with hard clipping you can still put out nearly 2000W of power! Dan Wiggins Adire Audio® [/QUOTE]

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