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New Guy .... Electrical System Question

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Old Jul 1, 2017 | 08:59 PM
  #1  
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Default New Guy .... Electrical System Question

Hello everyone.
First time poster. I've got a '13 Street Glide that I've added 6x9 in the saddlebag lids and two 8in woofers in a ATLANTA CUSTOM BAGGERS trunk. I'm planning on running a 300watt continuous power amp.

Will I have any alternator problems? ..... Electrical System is all stock.


Thanks!
 
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Old Jul 2, 2017 | 09:19 AM
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You will need to added up the current draw for all stock components and all accessories you plan to install. Check this against the current output of the stock alternator on the bike. I believe the stock alternator puts out 50 amps. The 300 watt continuous draw amp you are considering will consume half of what the stock alternator is capable of.
 
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Old Jul 2, 2017 | 11:38 AM
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Yep, what Boomer said. 300 continuous watts would consume 25 amps in current. However, if your amp OUTPUTS 300 watts of audio continuously then the current draw will be much higher. It takes more energy to make less energy. Your amp cannot be 100 percent efficient, if it's 50 percent efficient it will take 50 amps at 12 volts to generate 300 watts, if it's 75 percent efficient it will take 37.5 amps at 12 volts and so on and so forth.
Of course that's assuming you're listening to an amp that's always running at full volume and the music is never dynamic and is always at peak output.
In reality your music is dynamic and the large current pulls will come from your battery as they hold your current reserves. Measure the amp's current draw while listening at a normal level and this will tell you the average load placed on your electrical system.
 
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Old Jul 2, 2017 | 12:11 PM
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....some of the car audio guys will use a large capacitor to even out power surges ( with the bass) on the charging system...for a big old wacky audio system another battery could be added in the saddlebag.


But there is audio section on the forums and you should check in there- and be specific as to what equipment you are using.

"300 watts" is likely the "power output of the amp"-

the input power requirements will be in the manual.



i ( and many of us) use the rockford fosgate PBR300 amps.

different amps have different efficiencies amplifying sound.



Mike
 
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