In 1991, Etymotic Research introduced the world’s first earphones for music reproduction that were to be inserted into the ear canal. The ER-4S provided excellent isolation from outside noise and eliminated interactions with the pinnae, or outer ears, the shapes of which are different for each person, and thus are partly responsible for the widely varying perception of headphones’ sound. The design of the ER-4S was based on Etymotic’s extensive work in audiology, and informed by input from musicians and recording engineers. This combination of scientific and artistic approaches led to a product that was quickly adopted by many musicians, sound professionals, and audiophiles.

In the 20 years since then, many other companies have introduced competing products. Some are simply copies of Etymotic designs, some try to improve on them, and others only follow the basic form factor. All of these competitors must necessarily be compared to the prototype of the category: the still-available ER-4S or its more efficient sibling, the ER-4P. As a manufacturer in a product category in which model life spans tend to be short, Mead Killion, founder of Etymotic Research, believes in delivering a sound that’s faithful to the frequency-response curve that came out of his exhaustive research, and not bowing to fashion, or changing for change’s sake. The drivers of each set of ER-4 earphones are hand-matched and assembled at Etymotic’s headquarters in Illinois. Each set of ’phones comes with the resulting compliance chart, so that you know the unit you buy performs to specification.

Our own S. Andrea Sundaram reviewed the ER-4PT for SoundStage! Xperience, along with a cable that converts it to perform like the ER-4S. He found that the frequency response of the ER-4PTs was centered in the midrange, with a midbass and bass response that was slightly lower in level but still "quick, clean, and articulate." He also found the very top end to be slightly rolled off, though it "didn’t sound dull or muted, something that often happens when a design is intended to be forgiving." That combination of characteristics "put the emphasis squarely in the vocal range." In addition, Andrea found that "The individual timbres of voices -- the distinct character that makes each unique -- were also exceptionally well preserved by the ER-4PTs." He was even impressed with the ER-4PTs’ soundstaging abilities, and how they "managed to turn my skull into a recording studio or concert hall -- whichever was on the album." When he inserted the ER-P24 adapter cable, "the ER-4PT -- now equivalent to the ER-4S -- really did take on the sound of studio monitors in the nearfield."

Not a reviewer prone to raves, Andrea concluded with: "The Etymotic Research ER-4PT earphones -- and, even more, the ER-4S model -- provide reference-quality sound in a vanishingly small package. Their level of transparency of detail is beyond what I thought possible from this type of device. They really are like having studio monitors that you can take with you wherever you go."

While $299 might seem a lot to pay for an audio component weighing less than 25 grams, it’s about the least you can expect to spend on any product worthy of being called a reference component -- which Etymotic’s ER-4-series headphones are.

Manufacturer contact information:

Etymotic Research, Inc.
61 Martin Lane
Elk Grove Village, IL 60007
Phone: (847) 228-0006
Fax: (847) 228-6836

E-mail: customer-service@etymotic.com
Website: www.etymotic.com