Which ER•4 is Right for You?

Included with every pair of ER•4 earphones is an industry-exclusive channel-matching compliance graph, signed by the Etymotic engineer who precision matched and custom tuned the balanced-armature drivers.

ER4SR is Etymotic’s new reference standard hi-fidelity earphone, for those who demand nothing less than the highest fidelity. The next generation of our long revered flagship earphone, the ER4S, the ER4SR delivers increased accuracy with greater sound output, or sensitivity. Like its predecessor, the ER4SR channels are matched within an industry-leading 1dB across frequencies from 100Hz to 10 kHz. The new ER4SR incorporates significant cosmetic and functional improvements, from a sleek, anodized and laser-etched aluminum body to the reinforced, user-replaceable detachable cable. The ER4SR is a must have for discerning engineers, audiophiles, and consumers wanting the most accurate in-ear earphone available.

ER4XR is the earphone for music lovers and hi-fi enthusiasts who want uncompromising accuracy in the midrange and high frequencies, but appreciate a bit of extra presence in the lower end. Like the ER4SR, the ER4XR is built with precision machined, anodized and laser-etched aluminum bodies and features user-replaceable detachable cables. The ER4XR also incorporates the stringent channel-matching standard used in the ER4SR. The ER4XR is ideal for anyone looking for exceptional sound quality with just the right amount of low-end enhancement.

Accurate Earphone Reproduction

For earphones to have 100% accuracy, a recording of a live performance must produce exactly the same sound at the eardrum as the original performance. To achieve this, the acoustic properties of the ear must be factored in. The acoustic resonance and horn effects of the ear change a flat audio signal entering the open ear into sound with a (2700 Hz) high-frequency boost, which is the same response heard at the eardrum in a typical ear.

New ER4 Comparison Chart
New ER4 Comparison Chart