Sony® In-Ear Monitor Headphones

Product Overview

Faithfully reproduce every performance

With a Penta Balanced Armature system including magnesium super tweeter, integrated magnesium inner housing and an optimized sound path, these stage monitor headphones faithfully reproduce even the most subtle sounds and emotions.

Penta Balanced Armature system for optimal stage sound

For clean high notes, natural tones, and the pure emotion behind every performance, the IER-M9 has a Penta BA system including a magnesium super tweeter. Sony's original T-shaped Balanced Armature directly drives the diaphragm for more linear motion, and clean, faithful high notes.

Magnesium diaphragm super tweeter

The IER-M9 super tweeter diaphragm is made of lightweight and rigid magnesium alloy to deliver the fast dynamic transient of performance. The unique BA unit design also benefits from extremely low resonance thanks to high internal loss. Internal wiring is upgraded with a new silver-coated copper voice coil and gold-plated terminals, faithfully reproducing sound without sacrificing even micro signals so pitch, harmonics, and emotion are portrayed.

Audio grade film capacitor for less distortion

Our custom audio grade film capacitor in the cross-over circuit delivers much lower distortion. The audio grade capacitor of the IER-M9 delivers fine detail sound. Plus, audio grade solder also helps minimize any loss in signal path.

Beautifully designed for accurate tonal balance

With an integrated magnesium inner housing and optimized sound paths, the IER-M9 headphones deliver balanced tones and every nuance of your performance.

Integrated magnesium inner housing to reduce vibration

A highly rigid housing keeps the BA units firmly in place, helping to eliminate vibration and keeping sound clear without losing even the most minute detail in your sound.

Optimized sound path

A wide and short sound path made of magnesium alloy reduces frequency peaks and dips, to give a monitor sound you can rely on for critical listening accuracy.

Finer details and musical expression captured without loss

Silver-coated oxygen-free copper cables, a natural silk braid cable insulator with non-magnetic undercoat plug and a 0.17" standard balanced connection cable give less sound degradation, finer detail, and faithfully reproduced musical expression.

Balanced connection

A 0.17" standard balanced connection cable separates left and right sound signals completely, which minimizes cross-talk that results in sound deterioration.

Silver-coated OFC

Silver-coated, oxygen-free copper wire minimizes resistance and signal-transmission loss. The result is less sound degradation, finer detail, and smoother treble sounds.

Silk braid insulator and non-magnetic plug

Vibration is absorbed by the silk braid cable insulator to minimize rustling when the cord is touched. A gold-plated plug with non-magnetic undercoat preserves signal purity.

Detachable cable

The cable can be replaced if needed, or to fine-tune your monitor sound through a different cable.

Own the stage and the moment

The IER-M9 in-ear stage monitor headphones are designed to stay firmly in place so you can capture all the emotions you express in every performance.

Pre-formed ear hanger for easy positioning

The IER-M9 stably fit your ears thanks to the universally shaped ear hanger, which is easy to position even in the dark.

13 variations of earbuds

Six triple comfort and seven hybrid silicon earbuds let you find a snug fit for all kinds of ear shape. Combining hard silicone rubber and specially developed formed silicone, they perfectly match sound with stability and are comfortable to wear for long periods of time.

Light, durable magnesium outer housing

These in-ear headphones are designed for hard-wearing durability against knocks or accidents.

Stable fit

The IER-M9 are designed to stay firmly in place with a snug fit for all ear sizes. With a firm fit and optimal housing shape, each earbud stays in the right position, even while moving on stage.

Discover a new realm of musical expression, in the studio and on the stage with IER-M9 In-ear monitor headphones designed for musicians. With 5x unique Balanced Armature drivers from Sony, including a magnesium diaphragm and gold-plated terminals, every musical nuance is authentically reproduced.

Penta BA system

Magnesium diaphragm super tweeter

Sony's original design BA Driver Units

Light and durable magnesium outer housing

Pre-formed ear hanger for stable fit

Driver Unit: Penta Balanced Armature

Useful Documents