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Getting the power out of amp

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=7084
Printed Date: July 22, 2025 at 11:48 AM


Topic: Getting the power out of amp

Posted By: The Distortion
Subject: Getting the power out of amp
Date Posted: December 24, 2002 at 6:11 AM

An amp rated at 100 x 2 @ 4 ohms and 150 x 2 @ 2 ohms you need 2 ohm speakers to get it's full power, is there anyway to make the amp see a 2 ohm load with 4 ohm speakers without adding more speakers?

maybe by soldering "something"  inline of the wire(s)?




Replies:

Posted By: bberman1
Date Posted: December 24, 2002 at 9:28 AM
How many ohms are your speakers and are they dual voice coil (DVC)? Also is your amp bridgeable? And if so do you have the power ratings or model number of the amp?




Posted By: The Distortion
Date Posted: December 24, 2002 at 9:39 AM
It was just a general question, I really have no specs to throw at you, I was just wondering.posted_image




Posted By: bberman1
Date Posted: December 24, 2002 at 9:48 AM
Alright then if you have (2) 4 ohm (SVC) speakers and wire them together that will give you a 2 ohm load.




Posted By: The Distortion
Date Posted: December 24, 2002 at 10:00 AM

I gotcha, I was "thinking " their was some type of electronic doomajinger you could wire in that would "represent" itself as an extra  speaker to "fool" the amp into thinking it had two 4 ohm speakers hooked up and therefore sending out more power...I'm not even sure if that made sense

thanks!!!





Posted By: bberman1
Date Posted: December 24, 2002 at 6:01 PM
There is some type of electronic doomajinger it’s called a resistor. You can also get a 4 ohm resistor https://www.the12volt.com/resistors/resistors.asp Hook that up as well as your (1) 4ohm speaker and it will create a “dummy load” and give you 2 ohm load with just one 4 ohm SVC speaker.




Posted By: The Distortion
Date Posted: December 24, 2002 at 7:06 PM

Hope I did not offend you by calling a resistor a "doomajinger" , I know some people take car audio electronics very seriously. I just honestly did not know what it was.

Anyway the reason I asked  is because after that other post regarding the audiobahn six by nine rear fill speakers, I cancelled the order on the speakers and changed it to a set of MB Quart DSD 216 components.

I am going to place the infinity reference components in the rear as rear fill and the MBQuarts up front, the MB Quarts have a 50 to 120 watt rms range ,versus the 90 watts on the infinitys.

The amp I am going to power the MB quarts is a rockford fosgate power 350S 2 channel it has a 87.5 X 2 @ 4 ohms and 175 watts X 2 @ 2 ohms. Too much power for the MB Quarts yet I can back off.

Also I do not think I want to tackle this and even if I can use that resistor idea on a set of components, I think I am going to take my car into a professional custom car installer and see what ideas he has to tweak my system when i am done.

MERRY CHRISTMAS

 Manning





Posted By: dowheelies
Date Posted: December 25, 2002 at 5:59 AM

For anyone considering wiring a resistor inline DO NOT. Your amp WILL see a lower impedance load and work twice as hard to produce double(in a perfect world) the power output. However you will NOT get anymore power to to the speaker itself. All the additional power will be burned by the resistor and instead of being used to create sound energy will create heat energy. So in the end you end up putting additional strain and wear on your charging system and amplifier possably shortening their lives. You also loose available dynamic amplifier headroom that make those powerful transients all they can be. 

 There is/was a solution available from Stinger called the Accutap years ago that "fooled" an aplifier to think it was seeing a different load without "burning" the additional power. I'm not sure they are still sold. The conclusion we made at our shop at the time was the cost was high enough most of the time to recommend to customers to upgrade their amp or speakers to get the power outputs they wanted without any magic "doomajingers".

Hope this helps someone out,

Eric



-------------
2000 Lightning-Mods by Razors Edge 12.0@110. System by Alpine. Badazz mulch haulin' Vette killer!




Posted By: bberman1
Date Posted: December 25, 2002 at 9:44 AM
There was no offence taken. But as far as the wiring goes if you wire your two fronts together Then hook them up to one channel @ 2 ohms and then divide by 2 (for each speaker) you still get 87.5 watts per speaker. The only advantage you would have is you can use (1) 2 channel to power both the fronts and back speakers.




Posted By: The Distortion
Date Posted: December 25, 2002 at 9:59 AM

Ahhh I see! So the best way to get that max power rating (2 X 175 @ 2 ohms) is to connect a 2 ohm speaker to each channel, using two four ohm speakers  wired together splits that wattage between the two. I gotcha..thanks, Merry Christmas

oh yeah that was some good info dowheelies :)





Posted By: bberman1
Date Posted: December 25, 2002 at 10:05 AM
Glad to have helped you make some sense about how it works.





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