Ear Canal with Ear Drum

R2026b

Acoustic impedance of human ear canal and ear drum

Since R2026b

• 

Ear Canal with Ear Drum 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 / Human Ear

Description

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

This block simulates a human ear canal, including the ear drum, as defined in the IEC 60318-4 standard [1]. The block models the ear canal as a tube-shaped cavity using the Cylindrical Tube With Thermoviscous Losses Using Foster Network block. The block optionally models the concha, or outer pinna cavity, as another tube-shaped cavity. The block models the ear drum impedance, which includes partial canal length, identically to the Ear Drum Impedance block using the same equivalent circuit [2]. The figure shows the equivalent circuit of the block as a Simscape model with all components included.

Table 2 of the reference lists the default values for each inertance, compliance, and resistance component. The block measures pressure across the C5 compliance component and volume velocity through the C5 compliance component. Enable the pressure and volume velocity outputs using the Output pressure across C5 and Output volume velocity through C5 parameters, respectively.

Examples

New

Model Ear Canal

Model the acoustic response of an ear canal using Simscape™ Acoustics.

• Since R2026b
• Open Script

Ports

Output

P — pressure, Pa

physical signal

Physical signal output port for the pressure measurement.

Dependencies

To enable this port, set Output pressure across C5 to on.

U — volume velocity, m³ / s

physical signal

Physical signal output port for the volume velocity measurement.

Dependencies

To enable this port, set Output volume velocity through C5 to on.

Conserving

+ — Input acoustic terminal

acoustic

Input acoustic terminal of the ear canal.

Parameters

Concha Parameters

Include concha — Option to include concha

on (default) | off

Option to include the concha model in the ear canal with ear drum equivalent circuit.

Concha length — Length of concha

0.003 m (default) | positive scalar

Length of the concha in meters.

Dependencies

To enable this parameter, set Include concha to on.

Concha radius — Radius of concha

0.005 m (default) | positive scalar

Radius of the concha in meters.

Dependencies

To enable this parameter, set Include concha to on.

Canal Parameters

Canal length — Length of ear canal

0.0095 m (default) | positive scalar

Length of the ear canal in meters.

Canal radius — Radius of ear canal

0.0035 m (default) | positive scalar

Radius of the ear canal in meters.

Ear Drum Parameters

L1 — Inertance value of L1 in equivalent circuit

82.9 (Pa*s²)/m³ (default) | nonnegative scalar

Inertance value of the L1 inertance component of the ear drum equivalent circuit.

L2 — Inertance value of L2 in equivalent circuit

9400 (Pa*s²)/m³ (default) | nonnegative scalar

Inertance value of the L2 inertance component of the ear drum equivalent circuit.

L3 — Inertance value of L3 in equivalent circuit

130.3 (Pa*s²)/m³ (default) | nonnegative scalar

Inertance value of the L3 inertance component of the ear drum equivalent circuit.

L4 — Inertance value of L4 in equivalent circuit

983.8 (Pa*s²)/m³ (default) | nonnegative scalar

Inertance value of the L4 inertance component of the ear drum equivalent circuit.

L5 — Inertance value of L5 in equivalent circuit

133.4 (Pa*s²)/m³ (default) | nonnegative scalar

Inertance value of the L5 inertance component of the ear drum equivalent circuit.

C1 — Compliance value of C1 in equivalent circuit

0.7e-12 m³/Pa (default) | nonnegative scalar

Compliance value of the C1 compliance component of the ear drum equivalent circuit.

C2 — Compliance value of C2 in equivalent circuit

2.34e-12 m³/Pa (default) | nonnegative scalar

Compliance value of the C2 compliance component of the ear drum equivalent circuit.

C3 — Compliance value of C3 in equivalent circuit

1.5e-12 m³/Pa (default) | nonnegative scalar

Compliance value of the C3 compliance component of the ear drum equivalent circuit.

C4 — Compliance value of C4 in equivalent circuit

2.73e-12 m³/Pa (default) | nonnegative scalar

Compliance value of the C4 compliance component of the ear drum equivalent circuit.

C5 — Compliance value of C5 in equivalent circuit

1.517e-12 m³/Pa (default) | nonnegative scalar

Compliance value of the C5 compliance component of the ear drum equivalent circuit.

R2 — Resistance value of R2 in equivalent circuit

55.66e6 (Pa*s)/m³ (default) | nonnegative scalar

Resistance value of the R2 resistance component of the ear drum equivalent circuit.

R4 — Resistance value of R4 in equivalent circuit

27.99e6 (Pa*s)/m³ (default) | nonnegative scalar

Resistance value of the R4 resistance component of the ear drum equivalent circuit.

Additional Damping

Include R1 — Option to include acoustic resistance R1

off (default) | on

Option to include the R1 acoustic resistance component in the ear drum equivalent circuit.

R1 — Resistance value of R1 in equivalent circuit

4.22e5 (Pa*s)/m³ (default) | nonnegative scalar

Resistance value of the R1 resistance component of the ear drum equivalent circuit.

Dependencies

To enable this parameter, set Include R1 to on.

Include R3 — Option to include acoustic resistance R3

off (default) | on

Option to include the R3 acoustic resistance component in the ear drum equivalent circuit.

R3 — Resistance value of R3 in equivalent circuit

4.22e5 (Pa*s)/m³ (default) | nonnegative scalar

Resistance value of the R3 resistance component of the ear drum equivalent circuit.

Dependencies

To enable this parameter, set Include R3 to on.

Include R5 — Option to include acoustic resistance R5

off (default) | on

Option to include the R5 acoustic resistance component in the ear drum equivalent circuit. Including R5 significantly reduces the resonance of the model at 13.5 kHz.

R5 — Resistance value of R5 in equivalent circuit

3.22e6 (Pa*s)/m³ (default) | nonnegative scalar

Resistance value of the R5 resistance component of the ear drum equivalent circuit.

Dependencies

To enable this parameter, set Include R5 to on.

Optional Outputs

Output pressure across C5 — Option to output pressure across acoustic compliance C5

on (default) | off

Option to output the pressure measured across the C5 acoustic compliance component in the ear drum equivalent circuit.

Output volume velocity through C5 — Option to output volume velocity through acoustic compliance C5

on (default) | off

Option to output the volume velocity measured through the C5 acoustic compliance component in the ear drum equivalent circuit.

References

[1] IEC 60318-4:2010. "Electroacoustics — Simulators of human head and ear - Part 4: Occluded-ear simulator for the measurement of earphones coupled to the ear by means of ear inserts." International Electrotechnical Commission.

[2] Gazzola, C., V. Zega, A. Corigliano, P. Lotton, and M. Melon. “Lumped-Parameters Equivalent Circuit for Piezoelectric MEMS Speakers Modeling.” Proceedings of the 10th Convention of the European Acoustics Association Forum Acusticum 2023, January 17, 2024, 6307–14. https://doi.org/10.61782/fa.2023.0485.

Version History

Introduced in R2026b