Sennheiser HMD 280-13 Closed Headset, 300 ohms

Sennheiser HMD 280-13 Closed Communication Headset (300 Ohms)

The Sennheiser HMD 280-13 (Article Number: 004977) is a professional dual-sided circumaural (over-ear) communications headset designed for high-noise environments like broadcast TV control rooms, sports commentary booths, intercom stations, and industrial production fields. Built on the rugged physical platform of Sennheiser's workhorse HD 280 PRO monitoring headphones, this variant adds a noise-compensating dynamic microphone boom.

The "-13" designation indicates a highly specific system change from the standard standard HMD 280 PRO: it features upgraded high-impedance 300 Ohm headphone drivers instead of the typical 64 Ohm versions, making it compatible with high-voltage studio matrix intercom networks and professional broadcast consoles without overloading the gear.

Key Operational and Engineering Attributes

• High-Impedance 300 Ohm Voice Coils: Purpose-built for multi-user broadcast intercom systems (such as Riedel, Clear-Com, or RTS matrix stations). The higher load impedance limits current draw, which keeps distortion low and prevents the signal sagging that occurs when multiple headsets share a single communication line.

• Aggressive Passive Acoustic Attenuation: The sealed closed-back ear cup design provides up to 32 dB of passive external noise reduction. This isolates the operator from roaring crowds, engine noise, or control-room chatter, allowing for clear monitoring without cranking volumes to ear-damaging levels.

• Supercardioid Dynamic Microphone: Features a pre-mounted dynamic microphone capsule with a supercardioid pickup pattern. It is highly directional, capturing close-proximity speech while aggressively canceling out off-axis ambient room reflections and background stage noise.

• Flexible Swivel Boom Placement: The heavy-duty microphone boom arm rotates a full 270 degrees. This layout allows the headset to be worn flipped around, so the operator can position the mic boom on either the left or right side of their face.

• Unterminated Coiled Single-Sided Cable: Ships from the factory with a 1m to 3m coiled single-sided cable that is completely unterminated (bare copper wires). This allows system engineers to solder on whatever specialized terminal plugs their venue requires (such as a 4-pin female XLR for intercom systems, or a dual XLR/Jack combination for broadcast desks).

Technical Specifications Matrix

In the Box: Production Component Inventory

• 1 x Sennheiser HMD 280-13 Headset with Unterminated Coiled Cable

• 1 x MZW 4 Wind and Pop Screen Foam Cover

• 1 x User Safety and Wiring Schematic Manual

Field Configuration and Wiring Advice

Solder Mapping for 4-Pin Intercom Use: Because this headset ships with raw, bare wires, you will need to solder your own connector to interface with your gear. If you are configuring the HMD 280-13 for a standard broadcast production intercom matrix using a standard 4-Pin XLR Female connector, use this typical structural mapping scheme:

• Pin 1: Microphone Shield / Ground (-)

• Pin 2: Microphone Signal Positive (+)

• Pin 3: Headphone Ground Common (-)

• Pin 4: Headphone Signal Positive (+) (For mono links, bridge the left and right ear wires together onto this pin).

• (Note: Always check your specific intercom system manual—such as Clear-Com or RTS—before soldering to verify their factory input mapping).

Proper Dynamic Boom Placement: To get the cleanest signal and minimize vocal popping or heavy breath blasts from entering the communication line, do not place the dynamic microphone capsule directly in front of your lips. Instead, position the flexible boom arm so the capsule sits roughly 1 to 2 centimeters away from the skin, just off to the corner of your mouth. The directional supercardioid pattern will still capture your voice clearly while breath bursts blow harmlessly past the element.