6 Ch Amp with 8 Speakers

Printed From: the12volt.com
Forum Name: Car Audio
Forum Discription: Car Stereos, Amplifiers, Crossovers, Processors, Speakers, Subwoofers, etc.
URL: https://www.the12volt.com/installbay/forum_posts.asp?tid=75317
Printed Date: May 14, 2025 at 8:27 AM

Topic: 6 Ch Amp with 8 Speakers

Posted By: gonzo532
Subject: 6 Ch Amp with 8 Speakers
Date Posted: March 29, 2006 at 1:39 PM

Hello, I am in need of some advice.

I am an average installer, I can build boxes , upgrade a car stereo etc etc.

Here's my project:

I havea box with EIGHT 150Watt 6"x9" Kicker 3 Way Speakers.

I have a JL Audio Marine Amplifier Model# e6450M, Six Channel Amp.

What configuration should I use to connect 8 speakers to the 6 channels????

Here are the Amp spec's

Rated Power 12.5 V Stereo:	45W RMS x 6 @ 4 ohm 75W RMS x 6 @ 2 ohm
Rated Power 12.5 V Bridged:	90W RMS x 3 @ 8 ohm 150W RMS x 3 @ 4 ohm
Rated Power 14.5 V Stereo:	70 W RMS x 6 @ 4 ohm 110 W RMS x 6 @ 2 ohm
Rated Power 14.5 V Bridged :	140 W RMS x 3 @ 8 ohm 220 W RMS x 3 @ 4 ohm
THD at Rated Power:	12.5V: <0.08% THD, 20 Hz - 20 kHz 14.4V: <1% THD, 20 Hz - 20 kHz
S/N Ratio:	>104 dB referred to rated power (A-weighted, 20 Hz – 20 kHz noise bandwidth)
Frequency Response:	10 Hz – 25 kHz (+0, -1dB)
Damping Factor:	>200 @ 4 ohm per ch. / 50 Hz >100 @ 2 ohm per ch. / 50 Hz
Slew Rate:	± 22V / µs
Input Range:	200mV – 8V RMS
Dimensions (L x W x H):	17.70 in. x 9.25 in. x 2.36 in. 450 mm x 235 mm x 60 mm

Replies:

Posted By: DYohn
Date Posted: March 29, 2006 at 4:00 PM

First of all, why in the world would you want 8 3-way speakers in one box? But sure, since you must not be too concerned about how it sounds anyway, assuming the speakers are each 4-ohms connect two sets in parallel to two channels and the other four speakers to the other four channels.

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Posted By: forbidden
Date Posted: March 29, 2006 at 4:04 PM

Use 4 channels of the amp only. Parallel wire each pair of 6x9's to 2 ohm and connect to the 4 channels of amplification. Leave the other 2 channels alone for future use. DYohn's method will work fine as well.

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Top Secret, I can tell you but then my wife will kill me.

Posted By: stevdart
Date Posted: March 30, 2006 at 12:20 AM

Unscrew each one of them and frisbee them into the lake. See how far you can sail them. You'll have eight tries.

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Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.

Posted By: DYohn
Date Posted: March 30, 2006 at 12:31 AM

LOL

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Posted By: Velocity Motors
Date Posted: March 30, 2006 at 8:42 AM

lol

..... That's why I keep coming back here. You guys are a peice of work. posted_image

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Jeff
Velocity Custom Home Theater
Mobile Audio/Video Specialist
Morden, Manitoba CANADA

Posted By: gonzo532
Date Posted: March 30, 2006 at 10:10 AM

LoL, I know it's a weird setup. There is a reason and here it is:

The system is going into a brand spankin' new MasterCraft X2 ($70,000) wakeboard boat. The stock system comes wtih Four JL Audio Separates and One 10" Subwoofer all powered by a JL Audio Marine 4 CH Amp. My friend (boat owner) wants it this way so here I am asking for help.

The Box is an aerodynamic plastic material and made for the boat tower. Yes, it's a little overkill for tower speakers but it looks really good on the boat. In fact, the tower and 8 Kicker speakers only cost $600 vs. the box with four speakers for $400. It was a good deal at the boat show and it was somewhat of a drunk purchase.

My concern is this: If I run all these speakers on one amp on High Pass, Can I FRY the amp?? The amp has internal protection so I'd hope that would kick in before drawing too much off the amp. My friend really likes to turn up the music when the boat is underway (wakeboarder thing).

I'll hook it up using six channels, two channels will get four speakers in parrallel....See Diagram to confirm I'm good to go please!

Thanks so much, you guys are a wealth of info. Yes, you can laugh at my cheezy diagram.

posted_image

Posted By: stevdart
Date Posted: March 30, 2006 at 10:29 AM

Hmm, wonder how I knew you were on a lake? And lol to "It was a good deal at the boat show and it was somewhat of a drunk purchase." I can understand that!

You can't fry the amp as long as the impedance load per channel doesn't go below 2 ohms. You could hook up as many of the same-ohm speakers as you wanted to, using various parallel / series connections. The speakers don't "draw" off the amp, they just provide a resistance load that causes the amplifier to perform in a certain way, and then receive the output from the amp. The wattage is divided into the number of speakers according to their combined impedances per each channel.

So, per your diagram (which is quite good I think ;) if all channels are equal, each speaker will receive the same amount of power (most good amplifiers would result like this). Just two of the channels will be performing at a somewhat lower standard of quality (hotter) at 2 ohms, and the other four channels will be outputting at a cool 4 ohms.

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Build the box so that it performs well in the worst case scenario and, in return, it will reward you at all times.