Formula 4 finding Impedence Power Ratiing

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=14995
Printed Date: July 17, 2025 at 6:09 AM

Topic: Formula 4 finding Impedence Power Ratiing

Posted By: Lebult
Subject: Formula 4 finding Impedence Power Ratiing
Date Posted: June 15, 2003 at 7:01 PM

Hey guys,

I have a Sound Storm amp I'm using for my subs. Now, I wanna get another AMP for the rest of my speakers, but I wanna keep it Sound Storm. Make it a little neater, instead of 2 or 3 different brands lying around. I'm either gonna get one 4 Channel or 2 2Channel AMPS.

Here's the problem. The AMPs I want are a LITTLE too powerful for my speakers, so I wanna increase the Impedence (they're 4 Ohms now) to get them a little less power. But I can't find what the Power rating would be at 8 Ohms.

My question is, is there some sort of formula that I can use to find the Power Rating??

Replies:

Posted By: tdsteele
Date Posted: June 15, 2003 at 7:40 PM

How much is a "little" overpowered. It is possible to use a larger amp then what your speakers can handle if you keep the gains on the amp turned down to compensate for it.

Posted By: Lebult
Date Posted: June 15, 2003 at 10:30 PM

Ya, they're within Peak Rating Levels, but do I want to risk it?

The AMP pumps out 150 Watts RMS x 4, and my speakers are rated at 90RMS,270 PEAK (x2) and 70RMS, 210 PEAK (x2)

Posted By: bberman1
Date Posted: June 15, 2003 at 10:43 PM

You should be fine just turn don’t crank the gains up too high. If you hear the speakers distorting then turn the gains down until the distortion goes away.