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Showing posts with the label bass

What is a Bandpass Subwoofer?

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What exactly is a Bandpass Subwoofer?  Let’s take a look and see!   Along the way we will dispel some popular myths about bandpass subwoofers.   Forth Order Bandpass Subwoofer Enclosure The image above shows a speaker enclosure with the subwoofer mounted on an internal baffle that divides the box into two separate airspaces.   One of those chambers is sealed, one is ported.   At first glance this seems like an odd configuration.   How does it make any sound if the speaker is inside of the box?   The answer is simple once you understand that a port is just a speaker made out of air.   As the air in the ported side of the enclosure is compressed and decompressed it causes the air in the port to move back and forth and the port produces the sound.   A common myth is that the subwoofer driver makes the sound and the port “let’s the sound out”.   That is not accurate, what you are actually hearing is the sound waves produced by the port itself. DIY 4th Order It turns out that there

Subwoofer Ports

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Subwoofer ports (a.k.a vents) are interesting things.  In a previous post I provided some background into how ports worked , in this post I am going to dig a little deeper into port design, a.k.a. port tuning. Flared Ports with Wooden Connector Rings The Port Formula There is a formula that you can use to design a port, since formulas tend to scare people away and there plenty of tools available to do the calculations for you this blog post will focus on understanding the four main parameters that you need to think about when designing a port.  Tuning Frequency Enclosure Volume Port Cross Section Port Length We can manipulate any three of these four items and the formula dictates the forth parameter.  For this post we are going to examine how the tuning frequency, enclosure volume, and port cross section influence the length of the port.  It is very important to understand the impact of these four parameters as they will determine the size, shape and sound of our subwoofer.  We need to