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<blockquote data-quote="KooK" data-source="post: 8309454" data-attributes="member: 567461"><p>It depends on the situation. It's really basic math is the best way to figure it out. Amperage is Watts / Volts. If I buy a single SA-8 V.2 and have an amp pushing 600 watts at 13.8 volts, IF the amp reaches its max draw of 600 watts at 13.8 volts it is actually drawing 43.48 amps at that exact moment. Say I have the lights on and the AC running, I'm driving down the road and my car is currently taking 45 amps of power. Now that means that on hard bass hits I'm drawing roughly 88.5 amps from a 70 amp alternator, so it drains the system, lights dim for that moment.</p><p></p><p>Right there, what's happening to the alternator when it goes outside of its load range? Heat increases exponentially for each bass note!</p><p></p><p>Now, the factory battery is going to take some of the load off the alternator, so instead of the alternator receiving the entire 88.5 amp draw from the car and the bass note, it's now only receiving a 75 amp draw for that note because it's acting as a cushion which is a difference of 12.5 amps of overload the alternator isn't having to deal with.</p><p></p><p>What's happening to the alternator there? It's still going out of it's load range, heating up more than it should and the life is still shortened, but not as much because it doesn't have as much heat to it due to the peak draw being lower.</p><p></p><p>Finally, we add an auxiliary battery, it's not going to drop the 12.5 amps like your factory battery did, it's probably going to be more like a 6.25 amp drop from peak. So instead of the 88.5 draw with no batteries, the 75 amp draw with only one battery, we now have a 68.75 amp draw with two batteries, this will again decrease heat greatly because as I said, when the alternator goes out of its load range heat will increase exponentially.</p><p></p><p>BUT! Even though you're keeping that peak load off the battery, you are creating a more constant load because the batteries need to be recharged between bass notes. Ah, you see this is true, however I go back to where I state that the heat in the alternator rises exponentially when you get to the top of its range. If you were to evaluate X^2 (an exponential function) you will see that the higher the peak load is, the hotter the alternator will get vs a more constant high load with much lower peak values.</p><p></p><p>But what about long bass notes? Well that's why I specify what type of music I listen to. My bass notes are not long and drawn out in the music I listen to. If they were then the charging system would be much greater of a concern to me; if in a case I listen to Bass Nectar or something, I will probably have to turn off the A/C and/or turn the bass down a bit.</p><p></p><p>An auxiliary battery isn't something that will work for everybody, but it's something that will help out people in situations where the audio system is close to the peak power level of the charging system. You will shorten your lifespan of the alternator by putting this equipment in, in the first place. However you will lengthen the lifespan of the alternator from that if you were to install a cushion where there was not one.</p></blockquote><p></p>
[QUOTE="KooK, post: 8309454, member: 567461"] It depends on the situation. It's really basic math is the best way to figure it out. Amperage is Watts / Volts. If I buy a single SA-8 V.2 and have an amp pushing 600 watts at 13.8 volts, IF the amp reaches its max draw of 600 watts at 13.8 volts it is actually drawing 43.48 amps at that exact moment. Say I have the lights on and the AC running, I'm driving down the road and my car is currently taking 45 amps of power. Now that means that on hard bass hits I'm drawing roughly 88.5 amps from a 70 amp alternator, so it drains the system, lights dim for that moment. Right there, what's happening to the alternator when it goes outside of its load range? Heat increases exponentially for each bass note! Now, the factory battery is going to take some of the load off the alternator, so instead of the alternator receiving the entire 88.5 amp draw from the car and the bass note, it's now only receiving a 75 amp draw for that note because it's acting as a cushion which is a difference of 12.5 amps of overload the alternator isn't having to deal with. What's happening to the alternator there? It's still going out of it's load range, heating up more than it should and the life is still shortened, but not as much because it doesn't have as much heat to it due to the peak draw being lower. Finally, we add an auxiliary battery, it's not going to drop the 12.5 amps like your factory battery did, it's probably going to be more like a 6.25 amp drop from peak. So instead of the 88.5 draw with no batteries, the 75 amp draw with only one battery, we now have a 68.75 amp draw with two batteries, this will again decrease heat greatly because as I said, when the alternator goes out of its load range heat will increase exponentially. BUT! Even though you're keeping that peak load off the battery, you are creating a more constant load because the batteries need to be recharged between bass notes. Ah, you see this is true, however I go back to where I state that the heat in the alternator rises exponentially when you get to the top of its range. If you were to evaluate X^2 (an exponential function) you will see that the higher the peak load is, the hotter the alternator will get vs a more constant high load with much lower peak values. But what about long bass notes? Well that's why I specify what type of music I listen to. My bass notes are not long and drawn out in the music I listen to. If they were then the charging system would be much greater of a concern to me; if in a case I listen to Bass Nectar or something, I will probably have to turn off the A/C and/or turn the bass down a bit. An auxiliary battery isn't something that will work for everybody, but it's something that will help out people in situations where the audio system is close to the peak power level of the charging system. You will shorten your lifespan of the alternator by putting this equipment in, in the first place. However you will lengthen the lifespan of the alternator from that if you were to install a cushion where there was not one. [/QUOTE]
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