Ported Speaker Enclosure

R2026b

Model of speaker enclosure with up to three ports

Since R2026b

• 

Ported Speaker Enclosure block

To add a block to a model, double-click the canvas and start typing the block name. Then, select the block from the list.

Libraries:
Simscape Acoustics / Applications / Cavities and Enclosures

Description

Add-On Required: This feature requires the Simscape Acoustics add-on.

The Ported Speaker Enclosure block models a speaker enclosure with one, two, or three port tubes. The block assumes the dimensions of the enclosure are smaller than the acoustic wavelength at any frequency included in the analysis.

The model implements an equivalent circuit of an Acoustic Inertance block, which models the air mass at the rear side of the diaphragm, an Acoustic Compliance block, which models the air volume of the enclosure, and Acoustic Inertance and Cylindrical Tube With Thermoviscous Losses Using Foster Network blocks for each port. Each port connects internally to an Acoustic Reference block. The figure shows the equivalent circuit for an enclosure with two port tubes.

The compliance value of the block is

$$C=\frac{V_0}{\gamma P_0},$$

where:

• V₀ is the physical volume of the enclosure.

• γ is the ratio of specific heats of the medium.

• P₀ is the ambient pressure of the medium.

The inertance value of the air mass behind the diaphragm is

$$L=\frac{0.85\rho r}{A},$$

where:

• ρ is the density of the medium.

• r is the radius of the speaker diaphragm.

• A is the cross sectional area of the speaker diaphragm.

The inertance value of the air mass at each port entrance is

$$L_P=0.61\frac{\rho r_P}{\pi r_P^2},$$

where r_P is the radius of the port.

The Number of tube segments parameter sets the Number of differential tube lengths parameter of the internal Cylindrical Tube With Thermoviscous Losses Using Foster Network block in each port. The Tube length and Tube radius parameters of each internal Cylindrical Tube With Thermoviscous Losses Using Foster Network block are set by the corresponding port length and port radius parameters in the Ported Speaker Enclosure block.

Examples

New

Loudspeaker Enclosure Modeling with Simscape Acoustics

Simulate different types of loudspeakers using Simscape™ Acoustics.

• Since R2026b
• Open Script

Ports

Conserving

P — Input acoustic terminal

acoustic

Input acoustic terminal of the enclosure.

P1 — Terminal associated with first port

acoustic

Terminal associated with the first port of the enclosure.

P2 — Terminal associated with second port

acoustic

Terminal associated with the second port of the enclosure.

Dependencies

To enable this port, set Number of ports to Two or Three.

P3 — Terminal associated with third port

acoustic

Terminal associated with the third port of the enclosure.

Dependencies

To enable this port, set Number of ports to Three.

Parameters

Enclosure volume — Volume of enclosure

1 m^3 (default) | positive scalar

Volume of the enclosure in meters cubed.

Speaker diaphragm area — Area of speaker diaphragm

30.4 cm^2 (default) | positive scalar

Area of the speaker diaphragm in centimeters squared.

Number of ports — Number of ports in enclosure

One (default) | Two | Three

Number of ports in the enclosure, specified as One, Two, or Three. Increasing the number of ports adds additional parameters for the length and radius of each port.

First port length — Length of first port

10 cm (default) | positive scalar

Length of the first port in the enclosure in centimeters.

First port radius — Radius of first port

1 cm (default) | positive scalar

Radius of the first port in the enclosure in centimeters.

Second port length — Length of second port

10 cm (default) | positive scalar

Length of the second port in the enclosure in centimeters.

Dependencies

To enable this parameter, set Number of ports to Two or Three.

Second port radius — Radius of second port

1 cm (default) | positive scalar

Radius of the second port in the enclosure in centimeters.

Dependencies

To enable this parameter, set Number of ports to Two or Three.

Third port length — Length of third port

10 cm (default) | positive scalar

Length of the third port in the enclosure in centimeters.

Dependencies

To enable this parameter, set Number of ports to Three.

Third port radius — Radius of third port

1 cm (default) | positive scalar

Radius of the third port in the enclosure in centimeters.

Dependencies

To enable this parameter, set Number of ports to Three.

Number of tube segments — Number of lossy tube segments in port models

3 (default) | positive integer

Number of lossy tube segments in the port models.

Version History

Introduced in R2026b