Why not acoustic suspension?

Here ya go!

Acoustic suspension speakers are a specific type of sealed-box design that rely on a specially designed woofer and the air inside the cabinet for low-distortion, controlled bass, whereas general sealed-box speakers may not use this specialized driver design and may prioritize simplicity, compactness, and ease of construction.

Acoustic Suspension Speakers

Design Principle: Acoustic suspension speakers employ a woofer with very soft, compliant suspension components, and the air sealed inside the cabinet acts as a spring to return the cone to its rest position 

 

HUMAN Speakers+1

. This design provides a linear restoring force and reduces distortion, particularly at low frequencies 

 

Wikipedia+1

. The woofer’s mechanical suspension (spider and surround) primarily holds it in place without exerting most of the restoring force 

 

Audioholics

.

Performance Characteristics:

• Tighter, more controlled bass with a gentle roll-off (typically 12 dB/octave below resonance) 

   

  1

  .
• Lower distortion and better transient response compared to vented designs 

   

  2

  .
• Compact cabinet size with efficient bass performance, often delivering deep frequencies from a small enclosure 

   

  2

  .
• Precision and musical accuracy are prioritized over maximum output or absolute efficiency 

   

  1

  .

• 

  

  4 Sources

Applications: Ideal for hi-fi audio where accurate bass reproduction is more important than sheer bass extension or loudness. Often used in home stereo and critical listening setups 

 

HUMAN Speakers

.

General Sealed Box Speakers

Design Principle: A sealed box speaker, sometimes called a closed or sealed enclosure, does not have any ports or vents and relies on the air inside the box to provide some damping to the woofer 

 

All for Turntables

. Unlike dedicated acoustic suspension designs, it may use standard driver suspensions and does not necessarily optimize low-distortion bass behavior.

Performance Characteristics:

• Controlled bass with a smooth, gradual roll-off below the driver’s resonant frequency 

   

  1

  .
• Simpler and easier to build than an acoustic suspension system 

   

  1

  .
• Generally less sensitive and less efficient in producing very deep bass compared to acoustic suspension speakers of equal size 

   

  1

  .
• Still provides tight bass and works well in small spaces but may require more amplifier power to achieve the same output 

   

  2

  .

• 

  

  4 Sources

Applications: Commonly used in a variety of home and professional speakers, subwoofers, and bookshelf systems where simplicity, cost, and compactness are desired. These speakers may not attain the extremely low distortion levels of a true acoustic suspension speaker 

 

All for Turntables+1

.

Key Differences

Feature	Acoustic Suspension	Standard Sealed Box
Woofer design	Specialized compliant driver	Standard driver
Restoring force	Air spring in the cabinet	Combination of cone suspension and air
Bass roll-off	Gentle, 12 dB/octave	Gradual, may vary depending on driver
Distortion	Very low, well-controlled	Moderate; can vary
Cabinet size	Compact yet deep bass	Compact, sometimes less bass efficiency
Efficiency	Requires more power for same SPL	Slightly easier to drive
Application focus	Audiophile accuracy and transient response	Consumer or general-purpose use

In summary, all acoustic suspension speakers are sealed box designs, but not all sealed or closed boxes are true acoustic suspension systems. The former emphasizes specialized drivers and precise air-spring control to achieve high-fidelity, low-distortion bass, while the latter prioritizes simplicity and ease of integration into a room 

 

Audioholics+3

.

Why not acoustic suspension?

I prefer tuned and ported! 😎

See here and here.

Mike

@yogiboy Good read. In the case of the AR9, I believe that I read about the two 12 inch woofers in the bass cabinet portion were further calculated to "assist" each other in the same way as one works, in that "air compression" kind of assist, if that makes any sense.. My explanation is terrible I hope it can be understood. 

I have completely forgotten the name of the speakers I had as a kid.  They used passive radiators in the back, so they were in-between i suppose. 

 

But one day I removed the passive radiators, and sealed the holes shut with some round, wooden disc's i found at the local hardware store, and in my opinion, they performed so much better.  I could crank them so much harder without the woofers getting too wild.  The bass was tight as you would expect from a sealed box.

Passive radiators are a port substitute and basically give the same response as a ported speaker. There is no in between. If there is any in between perhaps it is a heavily stuffed port(variovent) which has no acoustic output but it ends up 12 dB like a closed box but it has tighter bass than an equivalent sized closed box. However an acoustic suspension woofer won't work in it.

Yogiboy did a pretty good explanation of acoustic suspension. My main minor gripe is where he says closed box roll off can vary. It ultimately becomes 12 dB per octave like all closed boxes of which acoustic suspension is as said a variation.