64 Audio U4s Universal In-Ear Monitors

A quad driver hybrid UIEM featuring ground-breaking patented technologies originally developed for our flagship products in order to bring a wider audience closer to their music.

tia™
A tubeless design that reduces resonance for a transparent and lifelike sound signature.

The tia system is comprised of three major elements: open balanced armature tia drivers, the tia single-bore design, and tia acoustic chambers. The U4s features two major elements of the tia system: the tia driver and the tia single-bore design.

The Tia driver is an open balanced armature speaker design for realistic resolution and transparency. By opening a balanced armature, the diaphragm becomes fully unobstructed, reducing resonance in the IEM and allowing sound to travel more naturally to the ear.

The Tia Single Bore is a huge advancement in eliminating unwanted tube resonance. The large bore itself serves as a sound-shaping chamber and aids the tia high driver in delivering a linear and coherent frequency response. The short sound path provides remarkable high-frequency extension and smoothness. The large single bore also allows for easier maintenance

apex™
Only from 64 Audio, apex alleviates listener fatigue by releasing air pressure sealed in the ear canal. This venting enables musicians and music enthusiasts to listen more comfortably for longer. Apex, or Air Pressure Exchange, is a pneumatically interactive vent that releases air pressure from a sealed ear canal. Apex comes in two variations, m15 (-15dB) and m20 (-20dB).

When you seal a miniature speaker in an ear canal, the air inside becomes trapped. Apex relieves this air pressure, allowing the eardrum to move naturally, so you can comfortably listen longer.

Freely moving air extends the soundstage and provides a more natural listening experience. It also preserves bass frequencies and helps the listener distinguish individual instruments.

LID™
LID, or Linear Impedance Design, enables a consistent, reliable sound regardless of what source. This proprietary circuit corrects the non-linear impedances of the drivers, restoring proper interaction with the source and preserving the desired sound signature.

Whether you're a musician plugging into a variety of gear at different gigs or studios, or an audiophile listening from low-impedance sources, LID ensures your IEMs are delivering the desired sound signature consistently.

And like all our IEMs, this model can be used with a wide range of personal audio devices as well as all hard-wired and wireless monitor systems.