Stereo Headset for Binaural Recording: Design

# Compact Stereo Headset for Precise Binaural Recording

An engineer created a compact stereo headset that enables recording, playback, and live streaming of binaural audio. The device simulates human ear acoustics in the ear canal, minimizing size without sacrificing quality. Key components: PUI Audio AOM-5024L-HD-R microphones and Knowles SR-32453-000 speakers, integrated into an elliptical housing 12 mm deep.

Prototyping Stages

Initial models used silicone ear replicas with WM-61 microphones connected to a Zoom recorder. Issues arose with resonances at high frequencies — tests on Metallica's "Fade to Black" revealed rattling in the guitar part.

Solution: Alginate ear molds, casting of silicone composite Shore A 40 whipped for a rough surface. Additionally, a wool filter at the microphone to suppress high-frequency resonances.

• Ear materials: tin-cure silicone, hardness 40 Shore A.
• Microphones: switch from WM-61 to PUI Audio AOM-5024L-HD-R (higher sensitivity, lower noise).
• Electronics: Zoom stereo recorder for precise recording.

Street tests confirmed realistic sound source positioning.

Design and Components

Prototype dimensions were reduced by mimicking earbuds: microphone and speaker in the ear canal provide stereo base, reflections, and permeability similar to a human head.

Knowles SR-32453-000 speaker (6 mm diameter, 4 mm thickness) with balanced armature delivers a flat frequency response and precise phase characteristics. Housing — elliptical plastic with a slant for secure fit.

Unbalanced connection with external shielding, cable in soft rubber to counter vibrations. The Zoom F1 recorder suits the prototype, but without mic-amplifier isolation — overload possible at high volumes. For refinement, Zoom F3 is recommended with balanced circuitry and high dynamic range.

![Knowles SR-32453-000 drivers]

Market Analysis of Analogs

Existing headsets don't fully implement binaural principles due to disrupted ear geometry and electronics.

• Sennheiser Ambeo Smart Headset: external housing shifts microphone outside the canal, no frequency response data.
• Roland CS-10EM: unbalanced connection, but geometry doesn't match the ear.
• DPA 4560-OC-B-B00: successful in-canal microphone (price ~$1230 USD), lacks speakers for monitoring.

The proposed model surpasses analogs in compactness and imitation accuracy.

Applications and Prospects

The headset works in mobile mode (worn on the head) or stationary (on a bust). Suitable for recording, live streaming, and active headphones. Patent RU222990U1 confirms novelty.

Demo content is limited, but tests show clear positioning.

Key Points

• Precise replica of ear canal geometry ensures binaural effect without a mannequin.
• Components: AOM-5024L-HD-R + Knowles SR-32453-000 for low noise and flat frequency response.
• Overload issue in Zoom F1 solved by isolation or balanced circuitry (Zoom F3).
• Market: Sennheiser/Roland analogs lose on geometry, DPA close but no speakers.
• Dimensions: 12 mm depth, elliptical profile for comfort.

— Editorial Team