Another amp wiring question

[Pinhacker71]

I will be installing 2 JL M600/6 amps with total of 1200 watts. Do I really need a 0 gauge power and ground cable, or can I use 4 g?

 

[tdonoughue]

It depends also upon the length of your run. See the sites like this one: http://www.engineeringtoolbox.com/amps-wire-gauge-d_730.html . When you do it, you probably want to put a factor of 2 or so for safety. So, you have 12 amps; I would figure for 24 or so. All of that said, when I did mine with one amp I did 0 gauge.

 

[Jackew]

I had the same question with my AR240 when I added my amps. I went the 4 and I always had over heating problems - always!

Then with my new boat I went with 0 wire, it has made a Hugh difference. Amps are never running hot like with 4 - plus I think I get better sound too.

Don't focus only on the wire - also make sure your connections are good! I went with heavy duty connection stright onto the battery and direct to my distribution block.

There is no such thing as overkill when it comes to powering high end sounds on a boat!

 

[Jackew]

Amp

• Jackew
• Jan 30, 2016

Here is the amps installed

 

[Pinhacker71]

Is there any reason I can't run power cable directly to the house battery? That is the only thing I'm using it for is the stereo. I would not think there would be a parasitic draw if amps power down the way they are supposed to when stereo is turned off. I would still have the house battery connected to the switch so it can be charged when underway. I just dread trying to attach the 0 gauge wire under the battery switcher housing.

 

[cozilla]

@Pinhacker71 I have a switch and ACR and I connected my amp power directly to my house battery. I also keep my batteries on a charger when not in use though.

 

[Pinhacker71]

That is exactly how I plan to set mine up. Just seems to make sense.

 

[David Analog]

Is there any reason I can't run power cable directly to the house battery? That is the only thing I'm using it for is the stereo. I would not think there would be a parasitic draw if amps power down the way they are supposed to when stereo is turned off. I would still have the house battery connected to the switch so it can be charged when underway. I just dread trying to attach the 0 gauge wire under the battery switcher housing.

Here's one reason to route the main audio supply through the battery switch. When the amplifier trigger is not receiving voltage the amplifier is 'Off' and cannot become a power drain. So that issue is not a problem battery-direct. So let's say you get hit with a storm and a serious wind-driven horizontal rain. Water can find its way everywhere including under a cover. Not usually a major problem in a small boat. It will drain and dry. But if the amplifiers are battery-direct and circumventing the battery switch, you have live power all the time entering the amplifiers via a 0, 2, or 4-ga. cable. However, the real potential risk in this case is all those paper thin traces on the inside of the amplifier. From water exposure the amplifier can go up in flames and do considerable damage to the boat without ever tripping a large fuse or breaker. In fact you can have a fire with just a couple of amps of current flow with this particular scenario. Is it likely? No. Is it possible? Yes. A boat owner can use a large master breaker as a safety disconnect. But he may not be as likely to every time he places the boat in a slip or on a trailer. And a large master fuse gives you no convenient disconnect option.
Or, perhaps you take a major roller over the bow that momentarily floods everything. Your electronics surviving may depend on how quickly you can isolate from the power source. Water exposure is one thing. Water exposure while passing current is a whole other matter.

 

[tdonoughue]

I like @David Analog 's response, but have an additional, more common application I suggest (which is why mine is attached to the switch):

If I want to work on the amp or its wiring for any reason and I want to make sure there is no power to it, I flip my switch and all power in the boat is off. Can I work around it by flipping my switch and then also removing the in-line fuse or battery cable? Sure. But just flipping the switch is much easier and eliminates my forgetting to unplug/disconnect one more thing before I work on the system.

 

[David Analog]

I like @David Analog 's response, but have an additional, more common application I suggest (which is why mine is attached to the switch):

If I want to work on the amp or its wiring for any reason and I want to make sure there is no power to it, I flip my switch and all power in the boat is off. Can I work around it by flipping my switch and then also removing the in-line fuse or battery cable? Sure. But just flipping the switch is much easier and eliminates my forgetting to unplug/disconnect one more thing before I work on the system.

A very good point by Tim. And it reminds me that the quickest way to do damage to a HU and introduce noise into the signal path is to unplug/plugin RCA cables while the system is powered up.