Introducció
This manual provides detailed instructions for the setup, operation, maintenance, and troubleshooting of your Sennheiser RS 255 TV Headphones. These headphones, also referred to as HDR 275 in some contexts, are designed to deliver clear dialogue and immersive sound from your television without disturbing others. The included BTA1 TV Transmitter facilitates wireless audio transmission.
Què hi ha a la caixa
Upon unboxing your Sennheiser RS 255 TV Headphones, you should find the following components:
- HDR 275 Headphones with User Replaceable Battery
- TV Transmitter BTA1
- TV Audio Digital (Toslink to Mini Toslink Optical Cable)
- TV Audio Analog (Audio Cable 3.5 mm)
- USB A-C Cable and USB C-C Cable
- User Information (this manual)

Figure 1: Contents of the Sennheiser RS 255 TV Headphones package.
Configuració
1. Càrrega dels auriculars
Before initial use, fully charge the headphones. The headphones feature a user-replaceable battery with up to 50 hours of battery life per charge.
- Connect the larger USB plug (USB-A) of the provided USB A-C cable to your TV's USB port (ensure TV power is on).
- Connect the smaller USB-C end to the charging port on the headphones.
- Alternatively, connect the USB-C cable to the BTA1 TV Transmitter, which also charges the headphones.
The LED indicator on the headphones will show charging status: red (0-10%), yellow (20-90%), and green (90-100%).

Figure 2: Charging port on the HDR 275 headphones.
2. Alimentació del transmissor
The BTA1 TV Transmitter receives power via a USB connection. This can be from your TV's USB port or a separate USB power adapter (not included).
- Connect the provided USB A-C cable to the transmitter's power input.
- Plug the USB-A end into a powered USB port (e.g., on your TV or a wall adapter).
3. Connexió a fonts d'àudio
The BTA1 TV Transmitter supports multiple audio input types. Choose the connection method best suited for your television or audio source.
Optical Audio Connection (Recommended for most TVs)
This digital connection provides high-quality audio and allows independent volume control for the headphones and TV speakers.
- Remove the protective cap from the blue-tipped optical cable.
- Connect one end of the optical cable to the "DIGITAL AUDIO OUT (OPTICAL)" port on your TV.
- Connect the other end to the "TV AUDIO" optical input on the BTA1 TV Transmitter.

Figure 3: Connecting the optical cable to the TV and transmitter.
Connexió HDMI ARC
If your TV has an HDMI ARC (Audio Return Channel) port, you can use this for digital audio. An HDMI cable is sold separately.
- Connect an HDMI cable (not included) to the "HDMI ARC" port on your TV.
- Connect the other end of the HDMI cable to the "HDMI" input on the BTA1 TV Transmitter.
Analog Audio Connection (3.5mm Headphone Out)
Use this connection for TVs or other devices with a 3.5mm headphone jack. Note that TV speakers may be disabled when using this output.
- Connect the provided 3.5mm audio cable to the headphone output on your TV or audio device (e.g., laptop, portable projector, AV receiver).
- Connect the other end to the "TV AUDIO" analog input on the BTA1 TV Transmitter.

Figure 4: Analog audio connection to the transmitter.
USB Audio Connection (PC/Mac)
For computers, the USB connection can provide both power and audio to the transmitter.
- Connect the provided USB A-C cable to a USB port on your PC or Mac.
- Connect the USB-C end to the power input on the BTA1 TV Transmitter.
- On your computer, go to Sound Settings and select "BTA1 TV Transmitter" as the audio output device.
Funcionament
1. Encendre/apagar
The headphones are pre-paired with the transmitter out of the box.
- To turn on: Press and hold the power button on the headphones.
- To turn off: Press and hold the power button for 3 seconds. The headphones will also automatically turn off after 15 minutes without an audio signal.
2. Control de volum
Adjust the listening volume using the dedicated volume up (+) and volume down (-) buttons on the headphones.
3. Selecció de la font
The transmitter automatically detects active audio signals. If multiple sources are connected, you can manually switch between them:
- Press the "SOURCE" button on the BTA1 TV Transmitter to cycle through available inputs (USB, HDMI, TV Audio).
- A solid LED next to the source indicates active audio. A blinking LED indicates no audio signal.
4. Modes de so
Enhance your listening experience with specialized sound modes:
- Claredat de la parla: Improves dialogue intelligibility, making voices crisper and easier to hear over background noise. Activate by pressing the "SOUND MODE" button on the transmitter until the corresponding LED illuminates.
- So envoltant virtual: Enhances depth and immersion, recreating a theater-like audio experience. Activate by pressing the "SOUND MODE" button on the transmitter until the corresponding LED illuminates.
- You can activate either mode, both, or neither, based on your preference.

Figure 5: Sound mode controls on the BTA1 TV Transmitter.
5. Smartphone Pairing and App Personalization
The Sennheiser Smart Control Plus app (available on App Store and Google Play) offers advanced personalization and control features for both your headphones and transmitter.
- Vinculació d'auriculars:
- Install the Smart Control Plus app on your smartphone.
- Press and hold the multifunction button on the headphones for 6-7 seconds until the LEDs flash blue to enter pairing mode.
- In your phone's Bluetooth settings, scan for devices and select "HDR 275" to pair.
- Open the Smart Control Plus app to manage headphone settings, including equalizer, sound profiles, hearing enhancements (Speech Clarity, Noise Suppression), and transparency mode.
- You can toggle hearing enhancements on/off with a quick press of the power button on the headphones.
- Emparellament del transmissor:
- Press and hold both the "SOURCE" and "SOUND MODE" buttons on the BTA1 TV Transmitter until the LED blinks green to enter pairing mode.
- In the Smart Control Plus app, use the device manager to add and connect to the "BTA1 TV Transmitter".
- Through the app, you can customize Auracast broadcast settings (name, encryption, listening device type), manage sound modes, and adjust audio sync for video delay.

Figure 6: Sennheiser Smart Control Plus App for advanced settings.
6. Auracast Technology
The BTA1 TV Transmitter supports Auracast, an exciting new wireless technology that allows you to broadcast audio to an unlimited number of compatible Auracast earbuds, headphones, or speakers simultaneously. Each connected device can have its own independent volume and sound settings.

Figure 7: Auracast allows multiple devices to connect to one transmitter.
Manteniment
1. Earpads Replacement/Cleaning
The earpads are detachable for easy cleaning or replacement. To remove, gently pinch and pull them off. To reattach, align and press them back into place.

Figure 8: Detachable earpads for cleaning or replacement.
2. Replaceable Battery
The headphones feature a user-replaceable battery, extending the lifespan of your product. Refer to the full product manual or Sennheiser support for detailed battery replacement instructions.
Resolució de problemes
1. No Audio Signal
If you are not hearing any audio, consider the following:
- Content Detection: Ensure your audio source is actively playing content. The transmitter requires an active audio signal to begin broadcasting. If you switch sources and hear nothing, try restarting the content.
- Dolby/PCM Settings: The transmitter can accept a Dolby-encoded digital signal. Most TVs handle this automatically. However, if you experience no sound, you may need to adjust the digital sound output format in your TV's settings menu. Look for options to switch between "Dolby" and "PCM" (Pulse Code Modulation). Refer to your TV's manual for specific instructions.
Especificacions
| Característica | Detall |
|---|---|
| Marca | Sennheiser |
| Nom del model | Sennheiser RS 255 TV Headphones |
| Número de model | 800142 |
| Color | Negre |
| Col·locació de l'orella | Sobre l'orella |
| Factor de forma | Sobre l'orella |
| Control de soroll | Cap |
| Durada mitjana de la bateria | 50 hores |
| Tecnologia de connectivitat | Wireless (Bluetooth, Auracast) |
| Versió Bluetooth | 5.4 |
| Mètode de control | Toca |
| Pes de l'article | 195 grams |
| Material | Plàstic, Teixit |
| Característiques addicionals | Virtual Surround Sound, Speech Clarity, Automatic Volume Levelling, Customizable Sound, Auracast Technology |
Garantia i Suport
Your Sennheiser RS 255 TV Headphones come with a 1-year manufacturer's warranty. For technical support, warranty claims, or additional questions, please contact Sennheiser customer support. You can also bookmark the official Sennheiser support weblloc per a futura referència.
For further assistance, refer to the official Sennheiser support channels or the full product manual.
Quick Start Video Guide
For a visual guide to setting up and operating your Sennheiser RS 255 TV Headphones, please watch the official quick start video below.
Video 1: Sennheiser RS 255 Quick Start Guide. This video provides a step-by-step walkthrough of unboxing, connecting, and using your TV headphones and transmitter.