So why are low volts bad?

[The Camry]

In the car audio world. We do everything we can to keep high voltages.

in the world of boat audio(i practically live at the lake in the summer). Most people have 4 tower speakers, 4 in boat speakers and a sub and they just run it all over a 2nd battery and start their boat every 30 min or so. They have to be having some seriously low voltage.

i dont get it. Why is low voltage so bad?

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[Kangaroux 5,000+ posts]

Low voltage means your system is straining. Say you're running a 1000w amp that's pulling 100A @ 14v, but you don't have the electrical to support it so your voltage drops as a result down to 11v. Now to achieve that same 1000w, you have to pull ~130A. As more current is drawn, your power wire will heat up more and so will your amp components, and heat is the #1 cause of failure for car audio equipment.

 

[bgowdy 5,000+ posts]

In the car audio world. We do everything we can to keep high voltages.
in the world of boat audio(i practically live at the lake in the summer). Most people have 4 tower speakers, 4 in boat speakers and a sub and they just run it all over a 2nd battery and start their boat every 30 min or so. They have to be having some seriously low voltage.

i dont get it. Why is low voltage so bad?

hmmm... my older bro has a bass boat simliar to this. He has a custom marine HU and marine speakers, and sub thats on his boat(hidden to keep from getting wet and a amp. He has his hooked into his boats battery bank which consist of 5-6 marine deep cycle batteries. He also runs all his boat light and what not on it and doesnt have issues with voltage.

 

[fly_marlin]

In the car audio world. We do everything we can to keep high voltages.
in the world of boat audio(i practically live at the lake in the summer). Most people have 4 tower speakers, 4 in boat speakers and a sub and they just run it all over a 2nd battery and start their boat every 30 min or so. They have to be having some seriously low voltage.

i dont get it. Why is low voltage so bad?

Besides being an indication that the system is demanding more power than being supplied, electronics such as amps and batteries don't like this very much. Standard battery would go bad after just 1 bad voltage drop. Amps can get damaged this way as well.

 

[los33 10+ year member]

Low voltage creates higher resistance towards pulling power. The more resistance the hotter everything gets.

Imagine voltage as a heartbeat, 14v is a steady beat, but the lower it goes the faster beats meaning its flowing faster.

Resistance is kind of like overlapping causing double the work.

Get it?

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[fly_marlin]

Low voltage creates higher resistance towards pulling power. The more resistance the hotter everything gets.
Imagine voltage as a heartbeat, 14v is a steady beat, but the lower it goes the faster beats meaning its flowing faster.

Resistance is kind of like overlapping causing double the work.

Get it?

Sent from my draconis using Tapatalk

Yeah, I don't know about all that. V=IR. Lower voltage means higher current, resistance doesn't chance with voltage. Resistance also doesn't make anything hotter, more current does.

 

[los33 10+ year member]

Yeah, I don't know about all that. V=IR. Lower voltage means higher current, resistance doesn't chance with voltage. Resistance also doesn't make anything hotter, more current does.

Yeah my post doesnt make to much sense... I give up trying to make sense anymore

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[noble brown]

Yeah, I don't know about all that. V=IR. Lower voltage means higher current, resistance doesn't chance with voltage. Resistance also doesn't make anything hotter, more current does.

Resistance is the direct cause of heat. If you could create a theoretical circuit with 0 resistance and infinite current you would have 0 heat. IRL, heat is only a secondary result of increased current draw because it always results in increased resistance.

 

[adulbrich 5,000+ posts]

Lower voltage requires more current. Amps are also less efficient at lower voltages. More current causes more heat, like stated above. Heat is bad

 

[wew lad 5,000+ posts]

go set the gain on an amp with a sine wave using an oscope with the alternator on, leave the wave unclipped but nearly clipping.

then do the same thing but dont touch the gain, and turn the vehicle off - use only your battery. now use the oscope on the outputs, the wave will be clipped.

i have pictures to prove this but it's a very interesting correlation and its surprising how much of a difference it makes

 

[n2audio 5,000+ posts]

A lot of the answers to this point are assuming the amplifiers in question have a lot of regulation built into the power supply.

Most common amps don't. When voltage drops they simply produce less power - drawing roughly the same amt of current. That's the main issue with low voltage.

A cheap amp that's 1000w at 14v is probably 700 or so at 12.

In most cases it's no big deal until the voltage drops to the point that the amp's low voltage protection shuts it down.