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Small black rectangular Bluetooth adapter with 3.5mm jack

GMCELL BT-29 Bluetooth 5.4 TX/RX Audio Adapter

SKU CH-QGRY-FBZ79 MPN BT-29

A 2-in-1 Bluetooth 5.4 adapter transmits audio from a 3.5 mm source to two headphones or receives streams for a car stereo

  • Amplifier ClassBT-29
  • CompatibilityApple AirPods, Apple AirPods Pro, Sony WH-1000XM5, Sony WH-1
  • FeaturesFlush Mount
  • Box Volume2.1082 L x 8.6106 W x 13.4112 H centimeters
  • ColorBlack
  • Dimensions4.8 in x 0.5 in x 1.4 in
  • TX mode streams TV audio to two headphones at once
  • RX mode adds Bluetooth to car stereo for hands-free calls
  • Bluetooth 5.4 gives stable pairing up to 10 m range
  • Compact 4.8 x 1.4 x .5 in design fits airplane seat pockets
  • SBC codec works with AirPods, Sony, Bose and any Bluetooth 4.0+ device

Dual-mode Bluetooth audio adapter

The GMCELL BT-29 is a compact 2-in-1 transmitter and receiver that adds wireless audio to devices with a 3.5 mm jack. In TX mode it sends sound from a TV, airplane seat or turntable to Bluetooth headphones. In RX mode it streams music from a phone to a car stereo or legacy hi-fi system. Bluetooth 5.4 provides fast pairing and a stable link up to 10 m (33 ft).

Sharing and hands-free calling

Two headphones can be paired simultaneously in transmitter mode, letting couples watch a film or listen to music together without cables. The built-in microphone enables hands-free calls when the adapter is used as a receiver in a vehicle. The SBC codec works with every Bluetooth 4.0 or newer headset, earbud or speaker, so no proprietary app or driver is required.

Codec and latency constraint

Audio is transmitted using the universal SBC codec, which guarantees broad compatibility but introduces latency that makes the adapter unsuitable for live instrument monitoring or competitive gaming. Buyers who need aptX Low Latency, aptX Adaptive or LDAC for real-time audio should look at a different solution.

Highlights

  • TX mode streams TV audio to two headphones at once
  • RX mode adds Bluetooth to car stereo for hands-free calls
  • Bluetooth 5.4 gives stable pairing up to 10 m range
  • Compact 4.8 x 1.4 x .5 in design fits airplane seat pockets
  • SBC codec works with AirPods, Sony, Bose and any Bluetooth 4.0+ device

Specifications

BrandGMCELL
SeriesBT-29
ModelBT-29
Amplifier ClassBT-29
Part NumberBT-29
CompatibilityApple AirPods, Apple AirPods Pro, Sony WH-1000XM5, Sony WH-1000XM4, Sony WF-1000XM5, Bose QuietComfort 45, Bose QuietComfort Ultra, Samsung Galaxy Buds, Jabra Evolve, Beats Studio Pro, Anker Soundcore, Any Bluetooth 4.0+ headphone
FeaturesFlush Mount
Box Volume2.1082 L x 8.6106 W x 13.4112 H centimeters
ColorBlack
Dimensions4.8 in x 0.5 in x 1.4 in
EnclosurePorted
FeatureFlush Mount
Frequency Response10Hz - 20KHz
Mounting Depth4.8 inches
Package Contain1
Ported Box Volume4.8 L x 0.5 W x 1.4 H inches, Ported
Sealed Box Volume4.8 L x 0.5 W x 1.4 H inches x 4.8 inches x 0.5 inches x 1.4 inches
Thickness4.8 L x 0.5 W x 1.4 H inches
Voice CoilBT-29
Voice Coil Constructiondynamic_driver
Crossover Frequency Range20 KHz
Speaker Level InputsActive
I/O PortsBluetooth

Questions about this item

How do I switch between transmitter and receiver mode on the BT-29?

Slide the TX/RX switch on the side of the BT-29 to the desired mode; in TX mode connect the 3.5 mm plug to the source, in RX mode plug it into the AUX input of the car stereo or speaker.

What happens when the built-in battery of the BT-29 no longer holds a charge?

The rechargeable cell is sealed inside the BT-29 and cannot be swapped; once it stops accepting a full charge the entire adapter must be replaced.

How long can I stream audio on the BT-29 before the battery runs out?

The BT-29 runs up to 10 hours on a full charge, so extended sessions such as a long flight or road trip are covered before you need to recharge via the USB-C port.

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