Etymotic ER4 XR Noise-Isolating Earphones with Etymotion Wireless Bluetooth Cable closed-back That's because we use similarly

That's because we use similarly designed acoustic transducers for both headphones

Detailed and balanced sound

both outer and inner edges of the “ring” are secured to the drive unit

they deliver an exceptional listening experience

Unlimited Sound

Etymotic ER4 XR Noise-Isolating Earphones with Etymotion Wireless Bluetooth Cable closed-back That's because we use similarlyOver 30 years ago, Etymotic invented noise isolating, in ear earphones. Etymotics original design, developed for auditory research and hearing testing, used balancedarmature receivers and established these speakers as the true reference standard for high definition, in ear earphones. Paired with the new Etymotion Wireless Bluetooth cable these earphones are unstoppable and sound better than anything else on the market today. With built in