Sennheiser IE 600

In-ears that hit the sweet spot

These traditional wired in-ear monitors (IEMs) are among my favorite headphones released this year. Sennheiser designed the IE 600 earbuds to split the difference between the punchy fun of their IE 300s and sharp technical prowess of the IE 900s. And to my ears, they nailed the sonic sweet spot. 

Like those other two models, the IE 600s feature a single dynamic driver inside each earbud. They also share a similar ergonomic earbud design — made of amorphous metal this time around, 3D-printed into shape and hand-finished. The result is a durable, comfortable set of IEMs, tuned for an engaging, musical sound profile with a delightfully prominent midrange. 

Sennheiser's high-precision drivers and advanced airflow system 

A single-driver design can lead to more cohesiveness than systems that use crossovers and multiple drivers. And Sennheiser's 7mm "TrueResponse" drivers can handle a wider frequency range than most. Still, it's a lot of ground for a single driver to cover — and sometimes competing sounds can be hard for our ears to distinguish.

So Sennheiser uses a dual "chamber within a chamber" absorber system to control airflow and help parse out musical nuances. This system uses damping material to cut down on resonance and keep similar-yet-different sounds from bleeding into each other. The result is full-bodied sound with effortless detail. 

Efficient design gives you many ways to play

Sennheiser designed the IE 300s to work with a portable music player — and even a phone or laptop. But I would suggest using a separate headphone amp to hear them at their best. Two detachable cables are included, one with a standard 3.5mm stereo miniplug and one with a 4.4mm balanced plug.  

I primarily used the latter connection on a forthcoming portable iFi Audio headphone amp/DAC combo, which paired up nicely with these headphones. This compact DAC was small enough to fit inside the zippered hard case included with the IE 600. So I could easily slip the entire premium listening rig inside my carry-on bag for my recent flight to Chicago for AXPONA — then stream Qobuz on my computer in the hotel. 

Secure and comfortable with a noise-isolating seal 

The most important touchpoint between sound and comfort is how well your earbuds fit. Of course, a proper, secure in-ear seal just feels right. But it can also make or break audio performance, including bass extension and imaging. 

Sennheiser includes six pairs of ear tips — three sizes of silicone tips, and three sizes of foam tips. For my ears, the largest foam tips squeezed right into place and didn't move. They expanded to create a noise isolating seal that avoided in-ear pressure points — and aligned the drivers correctly with my ears.