So…you want to buy a Subwoofer?

Speaker sphere

Buying a woofer? I received dozens of comments and questions on this subject last week. This is a loaded question. The absolute most important comment I can make is: match the woofer to the amplifier!

What does this mean? How do I do that? Try visualizing this:

If I have a 100-watt woofer, and the maximum movement of the woofer is one inch, this means it would take 100-watts to move the woofer in and out one full inch.


If I have two 100-watt woofers, of the example above, and only had 100-watts of power, each woofer would be getting one half of the amplifier’s power = 50 watts apiece. This would mean the woofers are only moving one-half inch! You are getting the same output from one subwoofer as you are using two.


If I have a 500-watt woofer and using the same example, if it takes 500-watts to move the woofer one inch in and out, a 100-watt amplifier would only move the woofer one-fifth of an inch. This means you get almost no bass from the 500-watt woofer because the amplifier doesn’t have enough power to move the woofer adequately.


The examples above are very simplified examples of amplifier power versus subwoofer power, but I think you get my point. I can get more output out of a 100-watt woofer than a 500-watt woofer with a small amplifier. This is something to really consider when buying or selling subwoofers. In the previous article, I mentioned why people are still buying Bazooka tubes even after twenty-plus years. Their system consists of a 250-watt amplifier with a 300-watt woofer in a very efficient cylinder-shaped enclosure. It is matched to the application, the amplifier to the woofer.


These points are critical to consider when replacing a stock subwoofer. If my 1998 Ford Explorer needs a factory replacement 125-watt eight-inch subwoofer and my replacement woofer is 400-watts, I will get significantly less bass output from the “upgraded” woofer. This will leave you feeling like you really wasted your money. This example is why it is essential to find a sales professional at your local store. Professionally trained sales staff will be able to make sure you get a matched woofer or woofers with your amplifier or help you purchase a “matched” set. As I have written in the past articles, the Internet’s best price does not mean it is correct for your application or desired output of your low down dirty bass applications.

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