Etymotic ER-4 Earphones have set the bar for noise-isolating earphones for more than 20 years now. First developed for auditory research, ER-4 Series earphones continue to deliver unsurpassed sound quality with response accuracy so good, it is the standard by which all other earphones are measured. Now the Etymotic ER-4 MicroPro Series puts audio technology precise enough for medical diagnostics into the hands of musicians, sound engineers, and audiophiles. Whether you are seeking reference-quality monitors or just an unparalleled listening experience, the Etymotic ER-4 MicroPro Series of noise-isolating earphones will deliver.
Elite Balanced-Armature Custom-Tuned Drivers
The ER-4 MicroPro is a world leader in sound reproduction. These are the only earphones with Accu-Driver™ balanced-armature, precision-matched drivers. These drivers have been custom-tuned to provide an impressive 86%+ response accuracy from 20 Hz - 16 kHz. Etymotic takes the custom tuning process seriously: each pair of ER4-PT earphones arrives with a channel-matching compliance graph signed by the engineer who did the tuning. The resulting high frequency-response accuracy, combined with the ER-4 MicroPro's best-in-class output sensitivity, creates superb, unsurpassed sound quality. This is the true, faithful, high-fidelity sound that musicians and audiophiles crave.
Best-in-Class Noise Isolation
The Etymotic ER-4 MicroPro provides excellent sound isolation, completely sealing the ear to block out 98% of external sound. That's about equivalent to 35 dB - 42 dB of noise isolation - a truly impressive feat for any earphone or headset, period. That much noise isolation has two big benefits. First, outside noises melt away, so you can focus on your music without the background noise - voices, traffic, other peoples' music, noisy neighbors. Second, the sound quality gets yet another boost. Without external noise to interfere, the sound that reaches your ears via the ER-4 MicroPro is so pure and clear, you may notice fine new auditory details that regular earphones just can't reproduce as faithfully. You will also be able to hear your music better at a lower volume than before, making it less likely that you will damage your hearing gradually by exposing yourself to too much volume over time. Serious noise isolation makes a serious difference.
The ER-4 MicroPro comes with an assortment of noise-isolating Accu-Fit™ eartips to ensure you can get a perfect fit from your in-ear earphones. The cable is braided and reinforced, and designed to keep the microphonic effect very minimal.
Etymotic ER-4 MicroPro - Watch the Video
Choosing the Right ER-4 MicroPro Model: ER4-PT vs ER4-S
We offer both the ER4-PT and ER4-S models of the Etymotic MicroPro series. The ER4-PT has greater output than the ER4-S, with 10 dB more output at higher frequencies and 13 dB more output in the lower frequencies. The ER4-PT also has a higher sensitivity and a more powerful bass, and it comes with the signed channel-matching graph. Meanwhile, the ER4-S is designed to provide accurate sound reproduction, compensating for the high frequency bias in CD recordings. The ER4-S boasts 92% response accuracy, versus the ER4-PT's 86%. The ER4-S's response is also similar to a typical monitor speaker, making it a popular choice for performing musicians to use as an in-ear reference monitor. The ER4-S may require a headphone amplifier for listening to low-power handheld devices. Both are favored by recording engineers and audiophiles.
Still not sure? The ER4-PT comes with a P-to-S adapter that converts the response accuracy from 86% to 92%. If you cannot decide between the ER4-PT and the ER4-S, opt for the ER4-PT - with the extra adapter accessory, it's a like getting both models in one.
20 Hz - 16 kHz
4S (100 Ohms)
4PT (27 Ohms)
Sensitivity (@1 kHz) SPL at 0.1v
4S (90 dB)
4PT (102 dB)
Maximum Output (SPL)
User Replaceable ACCU-Filters
ER-4 Attenuation Data
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