Sony Wireless Stereo Headphone System

MDR-RF855RK - Operating Instructions

WARNING

To reduce the risk of fire or electric shock, do not expose this apparatus to rain or moisture. Do not expose to dripping or splashing, and do not place objects filled with liquids on the apparatus. Do not open the cabinet; refer servicing to qualified personnel only. Do not install in a confined space. Connect the AC adapter to an easily accessible AC outlet.

CAUTION: Risk of explosion if the battery is replaced by an incorrect type. Do not expose batteries to excessive heat. Do not dismantle, open, or shred batteries. Avoid storage in direct sunlight. In case of battery leakage, do not allow liquid to contact skin or eyes. If contact occurs, wash with water and seek medical advice.

Do not use any charger other than the one provided. Secondary cells and batteries need to be charged before use. Always use the correct charger and refer to the manufacturer's instructions.

High volume may affect your hearing.

The validity of the CE marking is restricted to countries where it is legally enforced, mainly in the EEA and Switzerland.

Sony Corporation declares that this equipment complies with Directive 2014/53/EU and UK relevant statutory requirements. Full text of EU declaration of conformity is available at: http://www.compliance.sony.de/. Full text of UK declaration of conformity is available at: https://compliance.sony.co.uk/

Disposal of Waste Batteries and Electrical and Electronic Equipment: This symbol on the product, battery, or packaging indicates that they should not be treated as household waste. Recycle materials to conserve natural resources and prevent negative consequences for the environment and human health. Hand over products and batteries at end-of-life to appropriate collection points for recycling.

This product may interfere with pacemakers or other medical devices. Consult your doctor before use if you use such devices.

Features

Thank you for purchasing the Sony MDR-RF855RK Wireless Stereo Headphone System. This system offers:

Wireless headphone system with long battery life and 100 m range.
Hassle-free recharging by placing the headphones on the transmitter.
40 mm driver units for deep bass response.
Auto power on/off function for longer battery life.
Battery playback time up to 18 hrs with rechargeable batteries or 28 hrs with Sony alkaline batteries.

How to use

Insert the supplied rechargeable battery BP-HP550-11 into the left housing of the headphones. Observe correct polarity.
Connect the AC adapter to the AC outlet and the transmitter. Insert the plug firmly.
Charge the headphones. Place the headphones on the transmitter. The CHG/RED indicator lights up red. Charging is complete when the indicator turns off (approx. 7 hours for full charge).
Connect the A/V component to the transmitter using either the headphone jack or the audio out (L/R) jacks. Use the supplied connecting cable.
Wear the headphones. Lower the volume before listening to reduce the risk of hearing damage.
Start playback of the A/V component. The POWER/GREEN indicator of the transmitter lights up green.
Adjust the volume using the volume control on the headphones.

If you cannot receive a clear audio signal: Change the radio frequency using the CHANNEL selector switch on the transmitter and the TUNING switch on the headphones.

After use: The headphones automatically turn off when taken off (Auto power on/off function). Ensure the headphones are worn vertically for the auto power on function to work correctly. Do not pull up the self-adjusting band when not in use.

About sending RF signals: The transmitter sends RF signals when it detects an audio signal. Noise may occur depending on transmitter position and room conditions. Avoid placing the transmitter on a metallic table.

Automatic Transmitter Turn-off: If low signal or no signal is input for about 5 minutes, the transmitter turns off automatically. The POWER/GREEN indicator flashes green for 5 minutes, then turns off. Raise the volume of the connected A/V component if necessary.

Tips for charging

The supplied rechargeable battery is not charged initially; charge it before use.
Placing the headphones on the transmitter automatically turns them off and starts charging.
If the CHG/RED indicator does not light up red, check headphone placement and clean contact points if dusty.
Charging time is approximately 30 minutes to 7 hours.
To recharge after use, place the headphones on the transmitter.
Check remaining battery charge via the POWER indicator on the headphones. Charge if it turns off, dims, flashes, or sound becomes distorted.

Notes on Charging:

Insert the AC adaptor plug firmly.
Use only the supplied AC adaptor.
Battery capacity may decrease if headphones are left on and placed on the transmitter with the AC adaptor disconnected.
The transmitter automatically turns off while charging.
Only the supplied rechargeable battery BP-HP550-11 can be charged. Other batteries cannot be charged.
Dry batteries cannot be charged.
Do not use the supplied rechargeable battery for other components.
Charge in an environmental temperature between 5°C and 35°C.
Battery lifetime may be reduced by half when performance degrades. The supplied battery is not commercially available; order from your Sony dealer.

Using headphones with dry batteries

Commercially available LR03 (size AAA) dry batteries can be used. Install two batteries as described in step 1 of "How to use." The battery charge function is not activated when dry batteries are installed.

Battery life with dry batteries: Up to 28 hours with Sony alkaline batteries LR03 (size AAA).

Note: Do not carry dry batteries with coins or metallic objects to avoid short circuits and heat generation.

Tips for connection

Do not connect to AUDIO IN 1 and AUDIO IN 2 simultaneously.
If connecting to a monaural mini jack, the audio signal may not output through the right channel.

Tips for volume setting

When connecting to an A/V component's headphone jack, set the A/V component's volume as high as possible without distorting the audio signal.
Be careful not to raise the volume too high in quiet scenes when watching videos.

Tips for better reception

This system uses 800 MHz band signals, so reception may be affected by surroundings. Conditions that can reduce range or cause interference include:

Buildings with steel beams.
Areas with many steel file cabinets or metal furniture.
Areas with electrical appliances generating electromagnetic fields.
Placing the transmitter on a metal instrument.
Proximity to roadways.
Presence of radio transceivers (e.g., in trucks) or wireless communication systems along roadways.

The optimum distance is up to approximately 100 m without interference. This distance may vary. If noise occurs within this range, reduce the distance or select another channel.

Within the reception area, the transmitter can be placed in any direction. Some spots (dead spots) may exist where the RF signal cannot be received; this is inherent to RF signals and not a malfunction. Moving the transmitter slightly can change the location of dead spots.

Replacing the earpads

Remove the old earpad by pulling it out of the groove on the housing.
Place the new earpad on the driver unit, fitting the edge into the groove and turning it around the driver unit. Adjust the earpad to the vertical position. Earpads are not commercially available; order replacements from your Sony dealer.

Troubleshooting

No sound/Low sound: Check connections, ensure A/V component is on, adjust A/V component volume, change radio frequency, move headphones closer to transmitter, charge battery or replace dry batteries.
Distorted or intermittent sound: Move headphones closer to transmitter, avoid metallic tables for transmitter, adjust A/V component volume, change radio frequency, charge battery or replace dry batteries.
Loud background noise: Adjust A/V component volume, charge battery or replace dry batteries, avoid metallic tables for transmitter, move headphones closer to transmitter.
POWER/GREEN indicator flashes green: No signal or low signal detected. Start playback or increase A/V component volume. Transmitter will turn off automatically after 5 minutes of no/low signal.
Sound cuts off: Transmitter turns off after 5 minutes of no/low signal. Increase A/V component volume.
Battery cannot be charged/CHG/RED indicator issue: Ensure correct headphone placement on transmitter, use only the supplied rechargeable battery, clean contact points if dusty. If the indicator still does not light up, the battery may be at the end of its life.

Precautions

For long periods of non-use, disconnect the AC adaptor and remove the battery to prevent damage from leakage.
Avoid locations with direct sunlight, heat, or moisture.
Some noise may be heard when disconnecting the AC adaptor before removing headphones.
Avoid exposure to temperature extremes, direct sunlight, moisture, sand, dust, or mechanical shock.

Notes on headphones:

To reduce the risk of hearing damage: Avoid using headphones at high volume. Continuous, loud, and extended play is not advised. If you experience ringing in your ears, lower the volume or discontinue use.
Caring for others: Keep the volume at a moderate level to hear outside sounds and be considerate to those around you.

For questions or problems not covered in this manual, consult your nearest Sony dealer. Bring both the headphones and transmitter for repair.

Specifications

RF stereo transmitter (TMR-RF855R)

Modulation: FM stereo
Operating frequency: 863.0 MHz – 865.0 MHz
Maximum output power: < 4 mW
Channel: Ch1, Ch2, Ch3
Transmission distance: Approx. 100 m
Audio inputs: Pin jacks (left/right), Stereo mini jack
Power requirements: DC 12 V (from supplied AC adaptor)
Dimensions: Approx. 180 mm × 94 mm × 126 mm (w/h/d)
Mass: Approx. 310 g
Rated power consumption: 3.0 W
Operating temperature: 5°C to 35°C

Wireless stereo headphones (MDR-RF855R)

Frequency response: 10 Hz – 22,000 Hz
Power source: Supplied rechargeable nickel-metal hydride battery BP-HP550-11, or LR03 (size AAA) dry batteries
Mass: Approx. 280 g (including battery)
Operating temperature: 5°C to 35°C

Included items

RF stereo transmitter TMR-RF855R
Wireless stereo headphones MDR-RF855R
AC adaptor (12 V)
Connecting cable (stereo mini plug to pin plug × 2), 1 m
Rechargeable nickel-metal hydride battery BP-HP550-11 (550 mAh min.)
Card warranty
Operating Instructions (this manual)

Design and specifications are subject to change without notice.

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