ER2 Tubal Insert Earphones

The ER-2 TUBEPHONE Tubal Insert Earphones from Etymotic are specially designed to create a flat pressure response at the eardrum. ER-2 is intended for research purposes with humans and animals.

The bandwidth of the ER-2 is 16 kHz. The device impedance is 10 Ohms nominal; 12 Ohms @ 100 Hz; 8 Ohms @ 20 kHz. ER-2 delivers highly accurate and precise audio signals with a 70+ dB isolation between ears (reduces the need for masking) as well as a 30+ dB external noise exclusion. Different eartip sizes allow for convenient coupling to the ear. Individual frequency-response curves and distortion measurements are provided with each pair of ER-2 tubal insert earphones.

Note: Since the ER-2 input impedance is 10 Ohms, a low-output impedance signal source is required for constant voltage drive. Note the specifications and frequency-response graph. We recommend an amplifier with an output impedance of ≤1 Ohm.

Caution: This item is for research use only, and is not intended for clinical diagnostic use.

Comparison ER-1 and ER-2

ER-1 tubal insert earphones are designed to imitate the normal resonance of the open ear and to reproduce the same frequency response at the eardrum for speech that would be produced in a live situation (sound field).

ER-2 tubal insert earphones are designed to remove the 2.7 kHz ear canal resonance to create a flat pressure response at the eardrum.

Features

• Flat frequency response at the human eardrum
• For research with humans and animals when a 16 kHz bandwidth is required
• Accurate reproduction of signals recorded on the KEMAR® manikin (with flat-response microphone)
• 70+ dB isolation between ears: reduces the need for masking
• 30+ dB external noise exclusion

Technical Specifications

• 1 kHz Sensitivity: 100 dB SPL for 1.0 Volt (100mW) AV Drive; limits +/-3 dB
• Impedance: 10 Ohms (nominal); 12 Ohms @ 100 Hz; 8 Ohms @ 20 kHz
• Safe Operating Limits: Maximum continuous sine wave drive, 2.5 V RMS
• Maximum Peak Voltage for 1% Duty Cycle: 20 Volts
• Acoustic Polarity: + Electric (small pin) = + Acoustic

System Includes

• ER-2 TUBEPHONE Tubal Insert Earphones
• 7' cable assembly with dual-mono 1/4" male connectors
• 50 foam eartips (regular, 13mm)
• 10 foam eartips (small, 10mm)
• 2 Single Use Eartips™ adapters with tubing
• 2 sound-delivery tube replacements
• 1 Velcro neckstrap and 2 shirt clips

Instruction for Use

1. Examine the ear canal for obstruction or excessive cerumen.
2. Examine the eartip and the sound-delivery tubes to ensure they are not blocked.
3. Insert the clear tubing of the foam eartip completely onto the tip of the sound tube.
4. Roll the foam tip to a size that will fit the ear canal.
5. Insert the eartip well into the ear canal. Interaural attenuation is improved with deep insertion.
6. Allow foam to expand to acoustically seal the ear canal.
7. Eartips are single-use only.
8. Replace the sound tubes if they crack, harden, discolor or otherwise appear unusable.