2 ohm amp with an 8 ohm load
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=120653
Printed Date: May 13, 2025 at 7:58 PM
Topic: 2 ohm amp with an 8 ohm load
Posted By: red06g35
Subject: 2 ohm amp with an 8 ohm load
Date Posted: March 11, 2010 at 1:33 PM
Greetings,
I am installing a Polk db1040 DVC Subwoofer (4-Ohms/voice coil). I mistakenly ordered an amplifier that I belive is going to be too powerful for the subwoofer. Due to store return policies (not very flexible), I am afraid I am going to have to hold on to it and make it work. Here are the details:
The sub can handle between 50-270 watts RMS and a maximum of 540 watts. The amp purchased is an eclipse XA1200 which (according to the literature) puts out 350 watts RMS at 4-Ohms and 500 watts at 2-Ohms. I currently have the sub wired in parallel, to draw a 2-ohm load, however, the 2-Ohm power from this amp makes me think it will prematurely blow the speaker due to the power output.
My questions are these:
1. Am I correct in my assumption that running the amplifier at 2-Ohms on a regular basis (with a listed output of 500 watts) will prematurely damage my speaker?
2. If I wire the speaker in series, it is theoretically going to increase the impedance to 8-Ohms. Will this be too much impedance for the amp?
I understand that the higher the impedance, the less power that will reach the sub (but in this case, that may not be a bad thing).
Thanks in advance.
Replies:
Posted By: j.reed
Date Posted: March 11, 2010 at 4:09 PM
Having extra power on tap is not a bad thing. It called headroom and is a good thing. You should be able to give the sub all it will ever need and more of CLEAN power. Ensure the gains are set properly and you should have no problems running it at a 2ohm load. ------------- 
Posted By: smtgolf
Date Posted: March 11, 2010 at 10:38 PM
Just to correct note #2:
If it's wired in series, you are "decreasing" the impedance to 8-ohms. You are actually providing less resistance to the amp. If you are wired at 2 ohms, you are providing more resistance to the amp. The amp must work harder (output more power) to run the sub at 2 ohms vs. 8 ohms. It's an inverse relationship.
Check the stickies on Ohm's law to see the relationship between resistance and power.
Posted By: i am an idiot
Date Posted: March 11, 2010 at 10:49 PM
Posted By: the12volt
Date Posted: March 11, 2010 at 11:17 PM
smtgolf wrote:
Just to correct note #2:
If it's wired in series, you are "decreasing" the impedance to 8-ohms. You are actually providing less resistance to the amp. If you are wired at 2 ohms, you are providing more resistance to the amp. The amp must work harder (output more power) to run the sub at 2 ohms vs. 8 ohms. It's an inverse relationship.
Check the stickies on Ohm's law to see the relationship between resistance and power.
smtgolf, your statement is incorrect. Wiring in series will increase the impedance, not decrease it. 2 ohms is less resistance than 8 ohms, not more... -------------  the12volt • Support the12volt.com
Posted By: smtgolf
Date Posted: March 11, 2010 at 11:22 PM
Shoot, I didn't even notice that I reversed it...time to sleep. My fault on that one....I know better. Way too tired.
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