Introduction
The Sennheiser HMD 27 Professional Broadcast Headset is designed for broadcast commentators and audio engineers, offering high wearing comfort and excellent audio performance. This headset features a closed, circumaural earcup design for high passive noise attenuation, ensuring clear audio in demanding environments. Its lightweight construction and soft earpads provide comfort during extended use. The unique automatically opening two-piece headband distributes pressure evenly, preventing discomfort on the fontanelle. A wide headband padding is also included for users who prefer a conventional single-piece headband.
What's in the Box
Carefully unpack the box and ensure all items are present and in good condition. The package should contain:
- Sennheiser HMD 27 Headset
- Dynamic Microphone (integrated)
- Wide Headband Padding (for converting to single-piece headband)

Image: Side view of the Sennheiser HMD 27 headset, showing the circumaural earcups and the attached microphone.
Features
- Closed Circumaural Earcup Design: Provides high passive noise attenuation for effective sound isolation.
- Lightweight Construction: Designed for comfort during prolonged use.
- Automatically Opening Two-Piece Headband: Distributes pressure evenly to enhance comfort.
- Convertible Headband Option: Includes a wide headband padding to convert the two-piece headband into a conventional single piece.
- Dynamic Microphone: Features a hypercardioid pattern for focused voice capture and reduced ambient noise pickup.
- Wired Connectivity: Ensures reliable audio transmission.
- Soft Circumaural Earpads: Contribute to comfortable fit and sound isolation.
Setup
- Headband Adjustment: The headset features an automatically opening two-piece headband. To adjust for a comfortable fit, simply place the headset on your head. The headband will adapt to your head shape. If you prefer a conventional single-piece headband, attach the provided wide headband padding over the two-piece design.
- Microphone Positioning: Position the microphone boom arm so that the microphone is approximately 1-2 cm (0.4-0.8 inches) from your mouth. Ensure the microphone is aligned with your mouth for optimal voice capture. The boom arm is flexible and can be adjusted.
- Connecting the Headset: Connect the 3.5 mm audio jack of the headset cable to the corresponding audio input/output port on your device (e.g., computer, audio mixer, broadcast console). Ensure the connection is secure.

Image: Side view of the Sennheiser HMD 27 headset, demonstrating the adjustable microphone boom arm in an extended position.
Operating Instructions
- Audio Monitoring: Once connected, audio from your device will be routed through the headset's circumaural earcups. Adjust the volume on your connected device as needed.
- Microphone Use: The dynamic microphone is designed for clear voice transmission. Speak clearly and maintain a consistent distance from the microphone for best results. The hypercardioid pickup pattern helps to minimize background noise.
- Comfort Adjustment: During long sessions, periodically check the fit of the headset. The soft earpads and self-adjusting headband are designed for comfort, but minor repositioning may enhance long-term wearability.
Video: An overview of the Sennheiser HMD 27-Series Audio Headset, highlighting its features and design.
Maintenance
- Cleaning Ear Pads: Gently wipe the circumaural earpads with a soft, damp cloth. Avoid using harsh chemicals or abrasive materials. Ensure earpads are completely dry before storage or next use.
- Cleaning Microphone: Use a soft, dry cloth to wipe the microphone grille. Do not attempt to disassemble the microphone.
- Cable Care: Avoid sharp bends or excessive pulling on the cable. Store the cable neatly to prevent tangling and damage.
- Storage: When not in use, store the headset in a clean, dry place, away from extreme temperatures and direct sunlight.
Troubleshooting
- No Sound from Headset:
- Ensure the 3.5 mm audio jack is fully inserted into the device's audio output.
- Check the volume settings on your connected device.
- Test the headset with another audio source or device to rule out device-specific issues.
- Microphone Not Working:
- Verify the microphone boom arm is correctly positioned and not muted (if your device has a mute function).
- Check the microphone input settings on your connected device. Ensure the HMD 27 microphone is selected as the input device.
- Test the microphone with another application or device to confirm functionality.
- Discomfort During Use:
- Adjust the headband and earcup position to find the most comfortable fit.
- If using the two-piece headband, ensure it is properly seated. Consider attaching the wide headband padding for a different pressure distribution.
Specifications
| Feature | Detail |
|---|---|
| Model Number | 506902 |
| Headphones Form Factor | Over Ear, Circumaural |
| Color | Black |
| Included Components | Headset, Microphone, Wide Headband Padding |
| Noise Control | Sound Isolation, Noise Cancelling |
| Frequency Response | 20 KHz (Headphones) |
| Headphones Jack | 3.5 mm Jack |
| Connectivity Technology | Wired |
| Material | Metal (frame), Soft Earpads |
| Compatible Devices | Laptops, Audio Mixers, Broadcast Consoles |
| Cable Feature | Retractable (Coiled) |
| Item Weight | 12.5 ounces (0.78 Pounds) |
| Product Dimensions | 10 x 6 x 6 inches |
| Microphone Type | Dynamic, Hypercardioid |
| Impedance | 600 Ohms |
Warranty and Support
Sennheiser products are manufactured to the highest quality standards. For information regarding warranty coverage, technical support, or service, please refer to the official Sennheiser website or contact their customer service department. Keep your proof of purchase for warranty claims.
For further information, visit the product detail page.





