Etymotic Research ER4SR Reference Earphones Sennheiser our premium wireless speaker delivers

our premium wireless speaker delivers room-filling sound from a single source

Our patented algorithm perfectly compensates for the internal delay generated by a noise cancellation loop

The unique ear cup design directs sound waves to the ear at a slight angle to create an impressively natural and spatial listening experience

Crystal Clear Audio: Two Decades in the Making

Etymotic Research ER4SR Reference Earphones Sennheiser our premium wireless speaker deliversOverview ER4SR is the highest performing single driver in ear monitor. The IEM shells are made of anodized aluminum, CNC machined with extremely tight tolerances. Using a single Balanced Armature (BA) driver allows for extremely accurate IEM without the added complexity of crossovers, and helps keep the aluminum body small and slim. The included high quality user replaceable cable is reinforced and twisted, to improve longevity and durability.