Sealed, bandpass, ported, or tube? What are the differences ?


So, you think your music system setup needs a bit higher bass level. Naturally, you think about getting a subwoofer. You head down to a store, you ask for a subwoofer and the sales agent asks – sealed, bandpass ported or tube? Now, you look like a deer caught in the headlights. Hopefully, this scenario really hasn’t happened to you.

The world of subwoofers has evolved to a point that some people are lost when it comes to the different kinds and setup. To help with the confusion, this article is going to differentiate what is sealed, bandpass, ported and tube.


sealed-boxesSealed is the most common type of box. Furthermore, it’s the easiest kind to create. Think of it as subwoofer in a box. The insides of the box are also sealed as much as possible without putting the components at risk. This kind of box gives the finest overall bass sound quality, especially if you play music with lower frequencies. It also provides the flattest frequency response. On the downside, the setup is very dependent on the box. The internal volume needs to be fine-tuned correctly. The size of the box also matters as if it’s smaller that it should be, then more power is required. If it’s bigger, sound output will be muddy.


bandpassThe configuration of a Bandpass is composed of two boxes – ported and sealed. This setup oftentimes produces more bass when compared to ported or sealed boxes, especially if you test it on lower frequencies. However, the downside of Bandpass set up the optimum frequency range is rather narrow. This is because the setup mechanically bocks upper and lower frequencies. A Bandpass setup is usually big. Also, getting precise volume is a bit difficult. Keep in mind that Bandpas has a tendency to mask any distortion; hence it’s not good for certain music genres.


portedPorted are generally bigger when you compare it to the sealed boxes. The defining factor for this setup is a tube. The purpose of this tube is to allow air to move freely within and of the box. Sound travels through the air, and this are the idea behind ported boxes. Since the air can move freely, it can carry the sound waves from within, and out of the box. The box itself becomes like an amplifier. As a result, it produces more power compared to the other sealed-type of setups. On the downside, the box will act like a filter, which then cuts lower frequencies. Also, these kinds of boxes do not allow for a linear frequency response.


tube subwoffersThis setup is the best choice if your main concern is portability and space. The setup tightly packs a subwoofer, crossover and amplifier into one. It’s also cheaper in a sense that buying the components separately would result to more spending. The main downside of tubes is the lack of raw power.

So, that’s it. Hopefully, this article has defined what is a sealed, bandpass, ported or tube is. Keep in mind that each has its own strengths and weaknesses. It’s better that you get something that will fit your needs.