HMS II.7 – Fullband artificial head with free-field ICP^® microphones

HMS II.7 is the fullband artificial head equipped with two low-noise free-field ICP^®...

HMS II.7 is the fullband artificial head equipped with two low-noise free-field ICP^® microphones (left and right ear) and a two-way mouth loudspeaker. Therefore, the artificial head supports measurements in sending and receiving direction.

The the freefied-optimized artificial ears are equipped with pre-polarized ½” microphones providing a self-noise level of 15.5 dB_SPL(A). In combination with an upper sound pressure level limit of 135 dB_SPL, HMS II.7 covers most hands-free application measurements. The artificial mouth reproduces the complete spectrum of human voice, allowing narrowband, wideband, super-wideband and even fullband measurements. The head and torso simulator provides geometric and acoustic characteristics according to recommendation ITU-T P.58 and thus replicates all acoustically relevant structures of the human anatomy. With HMS II.7, users can create aurally accurate voice and audio recordings for analysis with the measurement and analysis software ACQUA.

HMS II.7 is ideally suited for all acoustical far-from-the-ear measurements of voice and audio quality. This includes automotive hands-free devices, smart speaker or conference phones. Since no impedance simulation is conducted, HMS II.7 is not suited for measurements of sound sources close-to-the-ear such as headphones, headsets, and handsets.

plus

Highlights

HMS II.7 is equipped with two low-noise free-field ICP^® microphones for binaural measurements
The artificial head enables testing close to or below the hearing threshold
HMS II.7 is suitable for far-from-the-ear measurements in sending and receiving direction
The artificial mouth and geometrical dimensions of HMS II.7 are compliant with recommendation ITU-T P.58

Applications

Free-field measurements in sending and receiving direction of sound sources far-from-the-ear
Voice quality and audio quality testing of e.g.:
- In-vehicle applications like hands-free terminals, in-car communication (ICC) systems, infotainment systems, emergency call (eCall) devices
- Voice-controlled smart home devices like smart speakers and other IoT devices
- Conference phones and hands-free devices

Features

Artificial free-field ears:

HMS II.7 is equipped with simplified pinna simulator and two high-sensitivity, low-noise binaural free-field ICP^® microphones.
The build-in ½” microphones provide an inherent noise level of typically 15.5 dB_SPL(A) and allow conclusive measurements close to or below the hearing threshold.
The upper sound pressure level limit of 135 dB_SPL ensures full usability of HMS II.7 for measurements at medium and high levels.
The artificial ears provide a transmission range from 3.5 Hz to 20 kHz.

Artificial mouth:

The artificial mouth with its two-way loudspeaker design transmits equalized speech signals from 50 Hz up to 20 kHz – from narrowband to fullband.
The two-way mouth simulator of the artificial head also reproduces high speech levels with low distortion.
Acoustic properties of the two-way mouth exceed the requirements of the recommendation ITU-T P.58.
Automated and comfortable equalization of the two-way mouth simulator is supported in the measurement and analysis software ACQUA.
Depending on the application, users can mount the artificial head on the height-adjustable tripod HMT III or on the torso box HTB VI.