2 ohms or 4? Bridge or not?

Echo Lodge · Jul 4, 2011

I am in the process of installing a new system in my roll bar boat. I have 4 Polk db series 6.5 inch in four cans on the tower. I have the same 4 speakers in boat. I am running a Crunch P5000.5 amp http://www.maxxsonics.net/manuals/crunch/pdfs/PowerZone%2008%20Amp%20Manual.pdf

I have a sony head unit that is 52x4 amp. I currently have the 5 channel amp powering the tower speakers and a bass tube. The head unit is powering the 4 interior speakers. Would I be better off running the tower speakers in parallel (2 ohms) off channel 1 and 2 and the interior speakers in parallel (2 ohms) off channel 3 and 4. Or leave the head unit to power the interior and bridge the amp to run the tower speakers? Or leave it how I have it?

SPL2K · Jul 5, 2011

Run all of the speakers off of the amp so they can all be crossed over correctly. Series the 2 left rollbar speakers together and the 2 rights together and run them off the rear channels of the amp. Then do the same with the interior speakers off of the front amp channels. Each amp channel will be running at 8 ohms. It will be slightly less power but still plenty loud plus voltage and heat wont be as much of an issue.

Echo Lodge said:
I am in the process of installing a new system in my roll bar boat. I have 4 Polk db series 6.5 inch in four cans on the tower. I have the same 4 speakers in boat. I am running a Crunch P5000.5 amp http://www.maxxsonics.net/manuals/crunch/pdfs/PowerZone%2008%20Amp%20Manual.pdf

I have a sony head unit that is 52x4 amp. I currently have the 5 channel amp powering the tower speakers and a bass tube. The head unit is powering the 4 interior speakers. Would I be better off running the tower speakers in parallel (2 ohms) off channel 1 and 2 and the interior speakers in parallel (2 ohms) off channel 3 and 4. Or leave the head unit to power the interior and bridge the amp to run the tower speakers? Or leave it how I have it?

Echo Lodge · Jul 5, 2011

SPL2K said:
Run all of the speakers off of the amp so they can all be crossed over correctly. Series the 2 left rollbar speakers together and the 2 rights together and run them off the rear channels of the amp. Then do the same with the interior speakers off of the front amp channels. Each amp channel will be running at 8 ohms. It will be slightly less power but still plenty loud plus voltage and heat wont be as much of an issue.

So even though the amp can do 2 ohms I will be better off running it at 8 ohms for the voltage and heat benefits? I do like the idea of running all speakers off of the amp as I can then use the head unit's fader for controlling sound above and in the boat.

SPL2K · Jul 5, 2011

Echo Lodge said:
So even though the amp can do 2 ohms I will be better off running it at 8 ohms for the voltage and heat benefits?

Running it at 4 ohms per channel would be ideal in a boat but you would need another 4 channel amp for that. Your next best option is 8 ohms. That 2 ohm rating is intended for automotive use where you have a continuous 14 volts and controlled temperature.

Even amps that are capable of running at 2 ohms are less efficient than at 4 or 8ohms which causes them to draw more power and create more heat.

Echo Lodge · Jul 5, 2011

Thanks.... I will give it a shot and see how things pan out.

linus3 · Jul 6, 2011

Eric had dinner with Paul tonight. Said you need to "bridge" which sounds like mentioned above.

Echo Lodge · Jul 6, 2011

linus3 said:
Eric had dinner with Paul tonight. Said you need to "bridge" which sounds like mentioned above.

The suggestion above was to not bridge the amp but to run the speakers in series.

http://www.termpro.com/articles/spkrz.html

This will change the speakers from 4 ohms to 8 and allow me to run all the speakers (tower and interior) off of the 5 channel amp.

Tom, it will also solve my wire issue as I can use the left over wires in the tower run to power the tower light speakers.

linus3 · Jul 8, 2011

sorry, thought bridging was that. My bad, anyway pull your head out and play some Abba already.

Echo Lodge · Jul 12, 2011

linus3 said:
sorry, thought bridging was that. My bad, anyway pull your head out and play some Abba already.

Anytime.... I am confident in my masculinity!

2 ohms or 4? Bridge or not?

Echo Lodge

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SPL2K

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Echo Lodge

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SPL2K

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Echo Lodge

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linus3

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Echo Lodge

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linus3

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Echo Lodge

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