Can I use Bluetooth to listen to music in my car?
What is Bluetooth?
Bluetooth technology was invented in 1994 by Ericsson engineer https://www.bluetooth.com/learn-about-bluetooth/tech-overview/. It was originally conceived as a wireless alternative to data cables. The name “Bluetooth” comes from a 10th century Scandinavian king, King Harold Bluetooth, who united dissonant tribes into a single kingdom. This analogous with Bluetooth technology’s ability to allow collaboration between different devices.
Bluetooth is a wireless communications protocol that allows devices to communicate over short distances using UHF radio waves in the ISM band from 2402 to 2480 MHz. Bluetooth employs frequency-hopping spread spectrum technology that chops up the data being sent and transmits chunks of it on up to 79 different frequencies. This helps minimize interference and enable the communication of multiple devices in a small area.
For streaming audio from a smartphone to a car stereo, the Advanced Audio Distribution Profile (A2DP) is commonly used. This profile allows high quality stereo audio to be streamed from one device to another over a Bluetooth connection. The A2DP profile has to be supported on both the source device (phone) and the receiving device (car stereo) for Bluetooth audio streaming to work.
Pairing Your Phone to Your Car
The first step in connecting your phone to your car stereo via Bluetooth is to make sure Bluetooth is enabled on both devices. On your phone, open the Settings app and ensure Bluetooth is turned on. For the car, consult your owner’s manual to enable Bluetooth on the infotainment system or stereo. Most cars have a Bluetooth option in the Settings or Connectivity menu1.
With Bluetooth activated on both devices, put your car stereo into pairing or device discovery mode. There is usually a Bluetooth or Add Device option in the menu. Your car stereo will become discoverable to your phone for pairing. On your phone, access the Bluetooth settings again and select the option to add or pair a new device. Your car stereo name should show up as an available device. Tap on it to begin pairing.
The final step is to confirm the passkey shown on both your phone and car stereo. This numeric code is randomly generated to secure the connection. Once confirmed on both devices, the pairing will be complete and your phone will connect to your car for streaming audio, hands-free calling, and more.
Streaming Audio Over Bluetooth
Bluetooth audio streaming allows you to play music wirelessly from your smartphone to your car’s speakers. When streaming over Bluetooth, the audio is compressed using advanced audio codecs before it is transmitted. This compression allows Bluetooth streaming to use very little data while still maintaining good audio quality.
There are a few main Bluetooth audio codecs used for streaming including SBC, AAC, aptX, and LDAC. SBC is the standard Bluetooth audio codec that all devices must support. AAC provides better quality audio and is used by Apple devices. aptX and LDAC are optional higher quality codecs supported on many Android devices.1
Because the audio is compressed, Bluetooth streaming uses very little data. It uses around 1-2 Mbps compared to WiFi streaming which requires at least 5 Mbps. This makes it very data efficient and you don’t have to worry about using up your phone’s data plan while streaming music in the car.2
Audio Quality
The audio quality when streaming music over Bluetooth depends on several factors including your phone, car stereo system, and Bluetooth codec support. Bluetooth audio quality is usually sufficient for listening to music while driving, but it’s lower quality than a wired audio connection.
Most modern smartphones support advanced Bluetooth audio codecs like AptX and AAC which can provide improved audio quality compared to the basic SBC codec. High-end car stereos may also support these advanced codecs, allowing you to stream music at near CD-quality bitrates up to 352kbps (1).
However, both your phone and car stereo need to support the same advanced codec to take advantage of the improved audio quality. If your car only supports SBC, you’ll be limited to bitrates around 256kbps even if your phone supports better codecs (2).
While Bluetooth quality may not match a direct wired connection, for many people it’s still good enough for listening to music during a drive. But critical listeners may notice degraded quality at loud volumes or with certain music genres (3).
Sources:
(1) https://www.nytimes.com/wirecutter/blog/what-you-need-to-know-about-bluetooth-audio/
(2) https://www.soundguys.com/understanding-bluetooth-codecs-15352/
(3) https://www.bowerswilkins.com/en-us/blog/sound-lab/is-bluetooth-audio-worse.html
Multi-Point Connections
Many modern cars support Bluetooth multipoint connections, allowing you to pair multiple phones to the car’s audio system simultaneously. This makes it easy to switch seamlessly between different audio sources. For example, you could be streaming a playlist from your phone, then answer a call coming through your work phone without having to repair devices.
Multipoint Bluetooth allows the car audio system to maintain connections with two or more devices at once. When audio starts playing on one device, it automatically pauses on the other connected devices. This enables easy switching between music, podcasts, phone calls, and navigation app directions from different phones or tablets connected to the car (Digital Trends, 2022).
One limitation is that the car’s audio system can only actively play audio from one device at a time. But the unused connections remain open in standby mode, allowing instant switching. Overall, multipoint Bluetooth makes it simple and convenient to connect multiple devices without having to constantly repair and disconnect.
Hands-Free Calling
One of the most useful features of Bluetooth in the car is the ability to make and receive phone calls hands-free. By pairing your phone to your car’s infotainment system via Bluetooth, calls can be handled through your car speakers and microphones.
This allows you to keep your eyes on the road and hands on the wheel while talking on the phone, which greatly improves safety while driving. Studies have shown that hands-free calling while driving is significantly less distracting and dangerous than holding your phone to your ear (1).
Once paired, your car can automatically connect to your phone when you start driving. Incoming calls will ring through your car stereo and you can answer them with buttons on your steering wheel or dashboard in order to start the hands-free call.
The built-in car microphones and sound system provide clear call quality on both ends of the call. This allows you to carry on natural conversations without the need to hold your phone.
Metadata Display
With Bluetooth audio streaming to a car stereo, song titles, artists, and playlists are conveniently displayed right on the head unit screen while you drive. This allows you to easily identify the music that’s playing without taking your eyes off the road.
Modern Bluetooth protocols support sending metadata like track title, album, and artist over an A2DP audio connection to a capable car stereo. This metadata is then shown right on the head unit display, updating in real-time as you skip tracks and select playlists.
However, some phones or apps may not fully support metadata display over Bluetooth connections. For example, according to user reports the Pixel 6 Pro and the latest version of Spotify may have issues displaying full metadata when streaming to a car stereo.
But when set up properly between the phone, app, and car stereo, metadata display over Bluetooth provides a great in-car music experience, allowing you to keep your eyes on the road.
Drawbacks and Limitations
While Bluetooth can be very convenient for streaming music and making hands-free calls in your car, it does come with some downsides compared to a wired connection.
The most notable drawback of Bluetooth is that it provides lower audio quality than a direct wired connection. Bluetooth audio is compressed to transmit over the air, resulting in some loss of fidelity compared to the original source audio. The difference may not be noticeable with highly compressed MP3s or streaming music, but high-resolution audio will suffer over Bluetooth.
Bluetooth connections can also suffer from intermittent delays, skips, or drops while streaming music. As you move away from your phone’s range, around 30 feet in normal conditions, the signal starts to degrade and audio cutouts become more likely. This can ruin your listening experience if you are trying to hear a podcast or audiobook.
The limited range is another constraint of Bluetooth technology. While 30 feet is enough for in-car use, it does mean you won’t be able to leave your phone in the house or back yard if you want to keep listening in the car. Obstacles like walls and wireless interference can further reduce the functional range.
Overall, the lower audio quality, connection reliability, and limited range mean that Bluetooth audio in cars can’t fully replace a direct wired connection. But for most people, the convenience of wireless streaming and hands-free calling outweighs the slight trade-off in audio fidelity.
New Car Tech
Major automakers are developing their own proprietary in-car tech that competes with standard Bluetooth. For example, BMW has iDrive, Audi has MMI, and Mercedes-Benz has COMAND. These systems often have tighter integration with the car’s controls and allow for more advanced voice control. However, they require learning a brand-specific interface and may not integrate as seamlessly with your phone [1].
In terms of voice assistants, many new cars are integrating with Siri, Google Assistant, and Amazon Alexa, allowing you to access these AI helpers through your car’s infotainment system. This allows you to place calls, queue up music, lookup directions, and more using just your voice. However, it does require compatibility between the car’s system and your phone’s OS [2].
Looking ahead, in-car audio is likely to become more personalized and adaptive. With the rise of streaming, cars may be able to learn your musical tastes and queue up customized playlists and stations automatically. Spatial audio is also coming to cars, allowing for a more immersive surround sound experience. And noise cancellation technology is improving, helping isolate and enhance the audio within the cabin. The goal is to create an effortless, tailored listening environment tailored to each driver and passenger [3].
Conclusion
This chapter has covered how you can pair your smartphone with your car’s infotainment system to stream audio over Bluetooth. We explored the ways Bluetooth allows you to wirelessly listen to music, podcasts, and audiobooks directly from your phone through your car’s speakers. While Bluetooth audio quality is not as high fidelity as options like auxiliary input or USB, it provides sufficient quality for most drivers’ needs.
The pros of using Bluetooth for in-car audio include the wireless convenience, ability to access playlists and apps on your phone, and built-in hands-free calling capabilities. The cons mostly relate to audio compression and potential connectivity issues. Overall, Bluetooth is a great option for drivers who want an easy way to go cordless and make calls while driving safely.
Bluetooth technology has advanced enough in recent years that it can provide a robust wireless music listening experience in the car for most people. While high-end audiophiles may still prefer wired options, Bluetooth has reached the point where it satisfies the in-car audio streaming needs of the average driver. As Bluetooth capabilities continue improving, it will only get better as a ubiquitous platform for in-vehicle smartphone integration.