EF-21942-000

Speakers Overview

The Knowles EF-21942-000 is a rectangular receiver speaker designed for audio applications. It features an impedance of 641 Ohms and operates within a frequency range of 200 Hz to 6.3 kHz. The component has physical dimensions of 7.87 mm x 5.59 mm x 4.01 mm. Sensitivity ratings vary by port configuration, with documented values including 122 dB and 126.5 dB depending on the specific variant or testing conditions.

Speakers Feature Summary

• Rectangular form factor suitable for compact electronic assemblies
• High impedance design optimized for specific driver circuits
• Available with top or side port configurations

Speakers Applications

• Receiver audio output in communication devices
• Portable electronic equipment requiring small form factors
• Industrial control panels with audio feedback requirements

Speakers Procurement Notes

Verify the exact port configuration (top vs. side) and sensitivity rating required for your design, as datasheets indicate variations. Confirm RoHS compliance status before ordering. Ensure mechanical clearance matches the 7.87 x 5.59 x 4.01 mm envelope. Cross-reference part numbers carefully to avoid confusion between similar Knowles receiver models.

Speakers Selection Notes

Select this component when high impedance matching is necessary for the audio amplifier stage. The rectangular shape aids in space-constrained PCB layouts. Consider the specific sensitivity requirement (122 dB vs 126.5 dB) based on volume needs. Verify that the 641 Ohm impedance aligns with the source circuit capabilities to ensure optimal power transfer and frequency response.

Speakers Part Context

This part belongs to Knowles' line of precision acoustic components. Receiver speakers like the EF-21942-000 are distinct from general-purpose loudspeakers due to their specialized impedance and frequency response characteristics. They are typically used in scenarios where clarity and specific electrical matching are prioritized over raw sound pressure level.

Speakers Replacement Considerations

Direct substitutes must match the 641 Ohm impedance and rectangular footprint. Check for identical port orientation (top/side) to maintain acoustic performance. No other specific replacement part numbers are publicly confirmed for this exact model.