how to 2 subwoofers/1 channel

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=115984
Printed Date: May 15, 2025 at 2:45 PM

Topic: how to 2 subwoofers/1 channel

Posted By: japd99
Subject: how to 2 subwoofers/1 channel
Date Posted: August 29, 2009 at 6:51 PM

I just had a 10 inch single sub installed on my 5th channel of a Memphis MCH600. It sounds incredible but in order to fit it in my Porsche, we had to take out a lot of the insulation in the back of the car. In a nutshell, when I'm on the highway or revving up the engine it's way too loud with engine and road noise. I found a guy who sells a custom box that will allow the insulation to go back in BUT I can only fit 8 inch subwoofers in it (either 1 or 2).

My question is: The current 10 inch sub I have is a Diamond D3/ 2ohms. The JL's are 4 ohms. How do I install 2 of these JL's without running into problems? I currently have 2 wires going to my D3 and I would like to get the new box with 2 speakers and only 1 connection to the subs. Will the two 4ohm subs mess up the amp? The amp says it can handle down to 1ohm with 400 watts on that 5th channel...

Please help!

Replies:

Posted By: i am an idiot
Date Posted: August 29, 2009 at 10:45 PM

Are the new speakers single or dual voice coil? That amp will run any load of 1 ohm or any higher number than 1. If the new speakers are single voice coi, 2 of them can be wired to give you either a 2 ohm or an 8 ohm load. If they are dual voice coil, you can wire them at 1 ohm, 4 ohm or 16 ohms.

Option 1 (parallel) = 2 ohm load
Speakers wired in parallel
Recommended Amplifier: Stable at 2 or 1 ohm mono

Option 2 (series) = 8 ohm load
Speakers wired in series
Recommended Amplifier: Stable at 4, 2, or 1 ohm mono

Posted By: japd99
Date Posted: August 29, 2009 at 10:53 PM

The new ones would be the JL 8w3v3. I don't think they are dual voice coil. How will this make a difference?

Posted By: i am an idiot
Date Posted: August 29, 2009 at 10:59 PM

A single voice coil has only one voice coil. Dual voice coil has 2. It makes a difference on the final impedance of your setup.

Option 1 (parallel/parallel) = 1 ohm load
Voice coils wired in parallel, speakers wired in parallel
Recommended Amplifier: Stable at 1 ohm mono

Option 2 (series/parallel) = 4 ohm load
Voice coils wired in series, speakers wired in parallel
Recommended Amplifier: Stable at 4, 2, or 1 ohm mono