Bluetooth makes it easy to enjoy wireless audio from your TV, phone, or tablet. Whether you’re connecting a pair of headphones for private listening or linking your TV to a Bluetooth soundbar for bigger sound, understanding how Bluetooth audio works can help you get the best experience — and avoid a few common surprises.
What Is Bluetooth Audio?
- Bluetooth is a wireless technology that sends data between devices using short-range radio signals. For audio, that means your TV (the source) sends a constant stream of sound data to your soundbar, speaker, or headphones (the receiver) without any physical cables.
- Because Bluetooth has limited bandwidth, it doesn’t send raw, uncompressed audio directly. Instead, the TV compresses the sound into a format called a codec before transmitting it. The receiving device then decodes that signal and plays it back through its speakers.
How Bluetooth Audio Is Transmitted
Every Bluetooth audio connection follows the same basic steps:
-
Pairing and Connection
The TV and the speaker or headphones find each other, pair, and agree on a compatible codec. -
Audio Compression (Encoding)
The TV’s Bluetooth system compresses the digital audio into smaller “packets” that can travel smoothly through the air. -
Wireless Transmission
These packets are sent over Bluetooth radio waves, typically within a range of about 30 feet (10 meters). -
Decoding and Playback
The soundbar, speaker, or headphones decode the packets and convert them back into audible sound.
This happens in real time — fast enough that you usually don’t notice any delay. However, depending on the codec used and the quality of the connection, you might experience a small amount of latency (delay between picture and sound).
Common Bluetooth Audio Codecs
A codec determines how your audio is compressed and how much detail is preserved. Different devices support different codecs. When two devices connect, they automatically use the best one they both understand.
| Codec | What It Does | Typical Use |
|---|---|---|
| SBC (Subband Codec) | The standard codec required in all Bluetooth audio devices. Reliable, but not as detailed as newer options. | All Bluetooth products |
| AAC (Advanced Audio Coding) | Efficient codec used heavily by Apple devices. Offers good balance between quality and stability. | iPhones, iPads, TVs, some Android devices |
| aptX / aptX HD / aptX Adaptive | Qualcomm’s family of codecs that improve sound quality and reduce delay. | Many Android phones, soundbars, and headphones |
| LDAC | Sony’s high-resolution codec that supports up to 24-bit/96 kHz audio at higher bitrates. | Select Android TVs and headphones |
| LC3 | The next-generation codec used in Bluetooth LE Audio for better quality at lower data rates. | Newer Bluetooth 5.2+ products |
If your devices don’t share a common advanced codec, they’ll automatically fall back to SBC. This ensures you’ll always get sound — though possibly at lower fidelity.
What Bluetooth Can’t Transmit
While Bluetooth is versatile, there are limits to what kinds of audio it can send. Here are the main ones:
-
No Surround Sound Formats
Bluetooth audio is generally limited to stereo (left and right channels). Surround formats such as Dolby Digital, DTS, or Dolby Atmos aren’t transmitted directly over Bluetooth.
Your TV will instead convert those signals into stereo before sending them to your Bluetooth device. -
No True Lossless Audio
Even the best Bluetooth codecs use some compression to fit audio within Bluetooth’s bandwidth.
High-resolution or “lossless” formats like FLAC or ALAC can be played by your device, but they’ll be compressed before wireless transmission. -
Limited by Hardware Support
Both your TV and your sound device must support the same codec. For example, if your TV only supports SBC and AAC, and your soundbar only supports aptX, they’ll still fall back to SBC. -
Latency (Audio Delay)
Some codecs add more delay than others. For watching TV or movies, low-latency codecs (like aptX Low Latency) help keep voices in sync with the picture.
Many TVs also have “lip sync” adjustments in the audio settings to help fine-tune timing.
Bluetooth vs. Wired or HDMI Connections
| Connection Type | Pros | Cons |
|---|---|---|
| Bluetooth | Wireless, convenient, compatible with many devices | May compress audio; limited to stereo; potential delay |
| Optical or HDMI ARC/eARC | Supports uncompressed multichannel formats like Dolby Digital and Atmos | Requires a physical cable |
| Wi-Fi (Wireless Sound Systems) | Can transmit higher-quality audio than Bluetooth | Often brand-specific (e.g., TCL, Sonos, Bose ecosystems) |
If your soundbar supports HDMI ARC or optical input, those options generally provide higher-fidelity sound than Bluetooth. Bluetooth, however, remains the most flexible and widely compatible wireless option.
The Future: Bluetooth LE Audio and LC3
Newer devices that support Bluetooth LE Audio use a more efficient codec called LC3 (Low Complexity Communication Codec). LC3 offers better sound quality at lower bitrates, improved battery life, and advanced features like:
- Multi-stream audio — perfect synchronization for both earbuds.
- Auracast — broadcast audio to multiple listeners (e.g., TVs in public spaces).
As more TVs, phones, and headphones adopt Bluetooth 5.2 or later, LE Audio will become the new standard — bringing higher quality and greater flexibility to wireless sound.
Key Takeaways
- Bluetooth sends audio wirelessly using codecs that compress and decompress the signal.
- Common codecs include SBC, AAC, aptX, LDAC, and LC3.
- Bluetooth is ideal for stereo audio, but not for lossless or surround formats like Dolby Digital or DTS.
- For the best lip sync and sound quality, use a wired or HDMI connection when possible — or ensure both your TV and audio device support the same advanced Bluetooth codec.
- The next generation, Bluetooth LE Audio, promises clearer sound and new listening features.