Enclosure types

How bass reflex, sealed, bandpass, horn, tapped horn and scoop work – with pros and cons.

Intermediate Bandpass Subwoofer: Driver Between Two Chambers In a bandpass, the driver sits between two chambers, and the sound only exits through ports. This gives a lot of level in a limited frequency band. 6th-order bandpasses...
Beginner Bass Reflex: How the Enclosure with a Port Works A bass reflex enclosure has a port in which air resonates. Enclosure volume and port form a Helmholtz resonator. Around the tuning frequency, the port delivers a large...
Beginner Sealed Enclosure: Air Spring Instead of a Port In a sealed enclosure, the driver works into a closed volume of air that acts like a spring. Below the resonance, the level falls at 12 dB per octave – more gently than...
Intermediate Bass Horn: How a Horn Increases Efficiency A horn does not amplify by itself; it couples the cone better to the air – like an acoustic transformer. This brings a lot of efficiency, but requires large dimensions...
Intermediate Hybrid Enclosure: When Principles Mix Hybrid enclosures combine several principles, for example a horn channel that at the same time tunes a compression chamber as a port. They are a compromise between size,...
Beginner Scoop: Short Horn Channel with a Side Effect A scoop guides the sound to the outside through a short, curved channel. It is more compact than a bass horn, but has limits: below its usable range the driver is barely...
Intermediate Tapped Horn: Both Sides of the Cone Feed a Horn In a tapped horn, the front and rear of the cone feed the same horn at two points. Both paths meet in phase at the horn mouth. The principle is considered particularly...
Intermediate Transmission Line and Quarter-Wave Enclosures In a transmission line, the rear of the cone feeds a long, damped line. Practical designs emit sound at the end of the line. Tuned as a quarter-wave resonator, the line...