How To Tell If A Car Amplifier Rating Is Too Good To Be True

One of the most popular questions we field here at Audio Designs and Custom Graphics revolves around amplifier rating and all the misinformation that goes along with it. So we thought we would share some real world facts with you to help you in making a more informed decision when it comes to buying a car audio amplifier.

There Are No “Wattage Police”

First and foremost, there are no “wattage police” out there to keep manufacturer’s honest. If Brand X wants to claim that their amplifier puts out 3000 watts when in reality it can only produce 300 watts, then no one is stopping them. That is the sad reality of the budget brands in car audio. What is so interesting here is that the top brands actually do some reverse marketing compared to the cheap brands in that they put conservative ratings on their amplifiers so they will actually outperform them. It is very common for a 1000 watt amplifier from a reputable company to put out 1150-1300 watts. What a far cry from the cheap brands.

So that all sounds good, but are there some signs that can indicate an amps real output potential? Great question. Here are some simple things to look for in an amplifier:

Fusing Is Key To Amplifier Rating

What is the total fuse rating on the amp itself? If an amp says it produces 3000 watts of power and it is a traditional A/B design, it’s maximum efficiency would be 60%. Let’s do some simple physics here (sorry for the math lesson… It’s important!)

Amp power = input voltage X current draw X amp efficiency

So if a normal car amp sees around 13.5 volts when the vehicle is running we know the input voltage is 13.5. We know the best efficiency a class A/B amp can have is 60%. And we know we want to get to amp power of 3000 watts. So….

3000 = 13.5 X 370.4 X .60

Whoa, that 3000 watt amp you can buy for $149 needs 370.4 amps of current to make 3000 watts. But wait, it only had a 25 amp fuse in it. What am I missing? Well…let’s run the formula again:

13.5 volts X 25 amps X .60 efficiency = 202.5 watts. In simple terms, you are not getting what you paid for. And that is why it was too good to be true.

CEA Rating

Look for a CEA Rating on the amplifier. CEA stands for Consumer Electronics Association, and if it has a CEA Rating for amp power, it is a reasonably good way to compare amp output between two amplifiers. One important note here is that many amps will put out significantly higher power when the amp sees a lower impedance, or load. We will gladly explain that for you if you stop by the store.

Output Voltage

Wattage is only one amplifier rating metric and is surely not the end all. What drives a speaker is voltage, not wattage. And it is possible to have three different amplifiers rated at 500 watts that will vary in their total output voltage capability. What does that mean to me? The higher the output voltage, the louder your system will play (all else being equal).

What is really important?  Size, Power and Reliability

In the end, what we feel is most important when choosing an amplifier is the following:  size, power, and reliability. If the amp will not fit where you need to mount it, then that amp is out. Will the amplifier reasonably power the speakers that best fit my needs? If so, then good. And most importantly, how reliable is the amplifier? Will it play for years to come and not overheat or go into protection mode and shut down?

Stop in and we will show you more!

We invite you to stop by Audio Designs and Custom Graphics in Jacksonville. We will be glad to elaborate on any of these topics and will gladly show you what we feel are the best sounding, most reliable amplifiers for your dollar. We like to think what makes us different is that we do not use a one size fits all template for our audio systems, but rather look at every customer and every vehicle differently, and we custom design and install the best solution for each person’s unique needs.  Stop in, give us a call or Contact Us today!