Ear Drum Impedance

R2026b

Acoustic impedance of human ear drum

Since R2026b

expand all in page
  • Ear Drum Impedance block

Libraries:
Simscape Acoustics / Applications / Human Ear

Description

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

This block simulates the impedance of an average human ear drum and part of the ear canal as defined in the IEC 60318-4 standard [1]. The block implements a proposed equivalent circuit of five Acoustic Inertance components, five Acoustic Compliance components, and two Acoustic Resistance components [2]. Optionally, you can include up to three additional resistance components, which provide additional damping for a better fit with real-world measurements [2]. The figure shows the equivalent circuit, found in Figure 2 of the reference, as a Simscape model with all components included.

Equivalent circuit to the Ear Drum Impedance block as a Simscape model.

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
Simulate Ear Drum

Simulate Ear Drum

Simulate the acoustic response of an ear drum using Simscape™ Acoustics.

New
Model an Inserted Earbud

Model an Inserted Earbud

Model the acoustic response of an earbud inserted into an ear using Simscape Acoustics.

Ports

Output

expand all

Physical signal output port for the pressure measurement.

Dependencies

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

Physical signal output port for the volume velocity measurement.

Dependencies

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

Conserving

expand all

Input acoustic terminal of the ear drum.

Parameters

expand all

Parameters

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

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

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

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

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

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

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

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

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

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

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

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

Additional Damping

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

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

Dependencies

To enable this parameter, set Include R1 to on.

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

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

Dependencies

To enable this parameter, set Include R3 to 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.

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

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

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

See Also