Four core technical parameters define the performance of the speakers: Sensitivity, Impedance, Frequency Range, and Speaker Dimensions.

1.Speaker Sensitivity (dB SPL/mW)

Sensitivity denotes sound output amplitude at a given driving power – higher sensitivity corresponds to greater loudness under identical power input. However, excessive sensitivity may induce background noise interference, necessitating precise impedance matching for optimal performance.

During in-house acoustic calibration, the primary objective is to achieve a refined balance between speech intelligibility and long-term listening comfort, thereby mitigating auditory fatigue for agents engaged in extended call sessions. Speakers with a sensitivity rating of 107±3dB SPL/mW fully comply with industry-specific standards for call center applications.

2. Impedance (Ω)

Typical impedance ratings for communication headsets include 32Ω, 64Ω, 150Ω, and higher values. Impedance refers to the electrical resistance presented by the speaker to alternating current (AC) audio signals.

The 150Ω configuration is optimized for compatibility with RJ-headset interfaces, as certain telephone systems exhibit significant volume attenuation when paired with 32Ω speakers. Customization with 32Ω speakers is available to accommodate specific customer requirements.

3. Speaker Frequency Range: 100Hz–6.8kHz

Frequency response defines the range of acoustic frequencies a speaker can reproduce. The theoretical standard for wideband voice communication is 50Hz–7kHz (±3dB). Call center headset speakers are acoustically tuned to this frequency band to ensure faithful reproduction of human speech, while actively suppressing extraneous high-frequency and low-frequency noise.

• Human Voice Fundamental Frequencies: Male voices range from 85–180Hz, and female voices from 165–255Hz. The 100Hz lower cutoff ensures coverage of fundamental frequencies and second harmonics for most human speech, preserving vocal richness and natural tonality.

• Ultra-Low Frequency Filtering: Frequencies below 100Hz primarily are dominated by ambient noise (e.g., HVAC systems, vehicular traffic). Active attenuation of these sub-100Hz frequencies minimizes interference and reduces overall power consumption of the speaker unit.

• Speech Clarity Core Band: Sibilants and fricatives in human speech concentrate energy in the 2kHz–6kHz range. Extending the upper frequency limit to 6.8kHz ensures complete retention of critical consonant details (e.g., /s/, /ʃ/ (sh) ), enhancing speech intelligibility in high-noise environments.

• Inaudible/Discomfort Zones: Frequencies below 50Hz are inaudible to the human ear; frequencies above 10kHz produce harsh, unpleasant tonal characteristics and are therefore excluded from the optimized response range.

4. Speaker Dimensions (mm)

Speaker size directly influences both wearing ergonomics and acoustic performance. An undersized diaphragm compromises low-frequency response, while an oversized design results in bulkier earcups that reduce long-term comfort. Inbertec employs ergonomic engineering to balance acoustic performance with wearability.

• Computer Headsets: φ30mm / φ40mm

• Call Center Headsets: φ28mm (standard) / φ30mm (optional) – Inbertec call center headsets primarily adopt φ28mm speakers, excluding aviation-specific models.

Key Advantages of Compact Speaker Design

The small outer diameter and streamlined upper/lower housing reduce the overall headset weight, which enables the headset to adhere to call center industry lightweight standards for prolonged wearing comfort.

Core Materials

High-grade neodymium magnets are integrated into the speaker assembly, delivering enhanced sound pressure level (SPL) output with differentiated manufacturing specifications tailored to professional communication needs.

Manufacturing & Performance Commitment

As a specialized headset manufacturer, Inbertec upholds stringent production criteria for call center headsets, prioritizing crystal-clear voice transmission and high-efficiency signal propagation to meet the demands of intensive communication environments.

The Essence of Inbertec Call Center Headsets

Exclusively engineered for high-intensity professional voice communication, Inbertec call center headsets feature superior ambient noise suppression, industrial-grade durability, and ergonomic comfort. Their core mission is to enable efficient, accurate, and reliable information exchange in mission-critical call center operations.