When it comes to speaker design, various enclosure types are used to achieve specific acoustic characteristics. One such enclosure design is the acoustic suspension, often referred to as a sealed enclosure. In this article, we’ll delve into the science of acoustic suspension, how it works, its advantages, and its applications in speaker design.
Understanding Acoustic Suspension
An acoustic suspension speaker enclosure is a sealed box that houses one or more speaker drivers, such as woofers or subwoofers. Unlike other enclosure types like bass reflex (vented) or transmission line, an acoustic suspension enclosure is airtight, with no ports or vents for air to escape.
How Acoustic Suspension Works
The primary principle behind acoustic suspension is the use of an airtight enclosure to create a spring-like effect on the diaphragm of the speaker driver. Here’s how it works:
- Airtight Enclosure: In an acoustic suspension design, the speaker driver is mounted inside a sealed enclosure. This enclosure traps a volume of air behind the diaphragm.
- Compliance and Resonance Frequency: The compliance of the air in the sealed enclosure acts as a spring, exerting a force on the speaker diaphragm. The diaphragm moves in response to the applied audio signal.
- Controlled Air Mass: The sealed enclosure controls the air mass and compliance, allowing the speaker designer to tune the resonant frequency of the speaker system.
- Damping: Acoustic suspension enclosures are known for providing tight and controlled bass due to their damping characteristics. The sealed box prevents uncontrolled low-frequency resonances that can lead to distortion.
Advantages of Acoustic Suspension Enclosures
Acoustic suspension speaker enclosures offer several advantages, making them a popular choice in various applications:
- Accurate and Tight Bass: One of the primary advantages of acoustic suspension enclosures is their ability to produce accurate and tight bass response. The sealed design minimizes resonances and provides precise control over the diaphragm’s movement.
- Reduced Distortion: The absence of vents or ports eliminates the potential for port noise or chuffing, common in bass reflex designs. This results in lower distortion, especially at low frequencies.
- Compact Size: Acoustic suspension enclosures can be more compact than their bass reflex counterparts while still delivering quality bass performance. This makes them suitable for smaller spaces or applications where size is a constraint.
- Durable Design: The sealed nature of acoustic suspension enclosures makes them less susceptible to dust and debris entering the cabinet, potentially damaging the driver or affecting sound quality.
Applications of Acoustic Suspension Enclosures
Acoustic suspension enclosures are commonly found in various speaker applications:
- Bookshelf Speakers: Many compact bookshelf speakers, designed for use in small to medium-sized rooms, utilize acoustic suspension enclosures to achieve accurate and controlled bass.
- Subwoofers: Sealed subwoofers are popular for home theater setups and music systems, where precise and deep bass is desired without the boomy character often associated with vented designs.
- Studio Monitors: Some studio monitor speakers, especially those designed for critical audio monitoring in recording studios, employ acoustic suspension enclosures for accurate sound reproduction.
In conclusion, acoustic suspension, or sealed enclosures, offer a unique approach to speaker design that prioritizes tight and controlled bass response with reduced distortion. While they may not be the loudest or most efficient in terms of bass output, their accuracy and compact size make them an excellent choice for various audio applications where quality bass is paramount.