Apogee Electronics Symphony Mk II Chassis with Thunderbolt 3 Interface Kit with Headphones (No I/O Modules)

Ideal as a starting point for building your custom pro audio interface build, this B&H Kit combines an Apogee Electronics Symphony Mk II Chassis with Thunderbolt 3 Interface (no I/O modules) with a pair of high-quality closed-back planar headphones. This gets you started while leaving room to select the I/O modules that best fit your needs.

Thunderbolt 3/4 Ready

Finally, you can enjoy all the features and modularity of the Symphony I/O Mk II series while exploiting the massive bandwidth afforded by Thunderbolt 3 technology. With universal USB-C connectors provided by the preinstalled Thunderbolt 3 option card, this interface can be easily integrated into the most modern workflows and is fully compatible with all computer and audio systems using Thunderbolt 3/4 or USB-C connectivity.

Rear Panel Slots

The rear panel provides access to the two I/O Module slots that are capable of a combined thirty-two channels of input and output, while the two Thunderbolt / USB-C connectors ensure compatibility with modern Windows and Mac computers. Also included are wordclock I/O connectors and termination, an option-card slot, and a quiet digitally controlled fan to keep everything running cool. The optional five I/O Modules allow the user to choose from standard configurations, or customize the following-channel count, analog to digital input, digital to analog output, microphone preamps (requires an analog card), and digital I/O.

Pristine Conversion

The Symphony I/O Mk II features a single ultrahigh-fidelity DAC and headphone amplifier with Apogee's Constant Current Drive technology, which was first introduced in the Apogee Groove. The headphone amplifier dynamically compensates for the nonlinearities of any connected headphones, providing massive power while maintaining extremely low distortion and linear frequency response.

Additional Details

Legendary AD/DA conversion

Up to 32 channels of modular analog I/O with optional 8 mic preamps

Ultralow-latency performance

Intuitive touchscreen display and front-panel control

Option-card slot for future platform flexibility

Dynamic Temperature Control

Designed in California, built in the USA

Benefits

Ideal for tracking and recording—Superior bidirectional passive noise reduction prevents microphone bleed

Low distortion protects hearing—Hear backing tracks with greater clarity — without boosting the volume

Precise response for accurate timing—Planar drivers offering pinpoint impulse response help you keep time with the music and stay on beat

Compatible with wide range of equipment—High-output, 18-ohm drivers peform well with most interfaces, mixers, laptops and mobile devices

Precision-Crafted Design

Built from premium magnesium, aluminum, and steel to ensure long-lasting performance. Magnetically attached earpads allow easy replacement and customization.

Effortless Comfort

Adjustable leather suspension headband and supple gel-filled earpads for hours of listening in luxurious comfort. Cable connects conveniently to either side.

Private Listening Space

Adjustable leather suspension headband and supple gel-filled earpads for hours of listening in luxurious comfort. Cable connects conveniently to either side.

SLAM-Symmetric Linear Acoustic Modulator

SLAM incorporates precisely engineered channels seamlessly integrated into the ring that connects the earpads to the drivers. Each channel’s length, cross-section, and shape are meticulously tuned through advanced simulations, precision measurements, and critical listening to achieve the ideal low-frequency response.

These acoustic channels relieve pressure buildup and acoustically modulate the low-frequency response, smoothly boosting bass, similar to adding a gentle low-frequency shelf. The result is significant bass enhancement, 6 dB or more extending as deep as 10 Hz.

A proper seal between earcups and ears inherently creates increased pressure between the ear and diaphragm. Consequently, the diaphragm faces greater resistance when compressing air toward the ear compared to when moving away.

SLAM resolves this issue by allowing controlled pressure equalization between the diaphragm and ear area, ensuring fully symmetric and uniform forces regardless of diaphragm direction. This linearized force significantly reduces distortion and improves transparency, adding openness and clarity to the soundstage.