High Performance Insert Earphones for EP / ERP applications:
- Unique design minimizes interference with ERP / EP measurements
- Predictable frequency response
- High isolation between ears: reduces the need for masking sound (* when used with a source having separate grounds for each channel – eg NOT a standard PC sound card)
- Eliminates collapsed ear canal problem
- 30+ dB external noise exclusion
Why do I need these special earphones for auditory EP / ERP applications?
- Calibratable – These insert earphones have optimally-flat frequency response. So, no matter the frequency of the sound you play, you can apply a single scale factor to achieve relatively accurate control of sound-pressure at the earphone.
- No stimulus artifact – The transducer is a few inches from the electrodes so you will not see a stimulus artifact in the recorded EEG.
- Predictable timing – The time it takes for sound to travel from the transducer to the ear is exactly one millisecond, and you can take that into account in your measurements.
Can I use standard earphones or speakers?
- Standard headphones will interfere with the EEG recording.
You can use loudspeakers, but we recommend against that because:
- Loudspeakers sometimes produce stimulus artifact
- Sound pressure levels depend on the exact head position relative to the speaker.
- Loudspeakers typically have irregular (not flat) pass bands, making calibration across frequencies a challenge.
- Time delay from speaker to ear depends on distance and head-position, so it is impossible to know the timing delay to the ear without carefully measuring the distance between the speaker and the ear.As
- 1 kHz sensitivity: 105 dB SPL for 1V rms drive
- Impedance: 10 Ohms nominal
- Acoustic Polarity: + Electrical = +Acoustic
- Typical Frequency Response (Zwislocki Coupler) at right
Copyright © Etymotic Research, Inc.
Showing 1–16 of 21 results
ER-2 Insert Earphones- Flat frequency response at the human eardrum
ER-30 Insert Earphones- For use in magnetically unfriendly environments
ER-1 Insert Earphones- Flat frequency response referenced to the sound fiel
ER•3C Insert Earphones – 10 Ohm
Sound attenuating over-the-ear phones for parent/participant
Dual-Mono Cable 7ft Assembly for ER-1 Insert Ear Phones
Disposable foam eartip baby (10 mm) for use with ER-3A (pkg of 50 ea)
Disposable foam eartip regular (13 mm) for use with ER-3A (pkg of 50 ea)
Disposable foam eartip jumbo (18mm) for use with ER-3A
4mm infant eartip for ER-3A
3.5mm infant eartip for use with ER-3A
Disposable foam eartip baby (10mm) for use with ER-1 and ER-2 (pkg of 50 ea
Disposable foam eartip regular (13mm) for use with ER-1 (pkg of 50 ea)
Sound delivery tube replacements with adapters for ER1 phones
Sound delivery tube replacements with adapters for ER3
Front tube adapters for ER-1, pkg of 10