Imagine someone told you eight years ago that understanding Bluetooth codecs would be commonplace by 2021. We would say there’s a better chance that Donald Trump becomes President of the United States. It just goes to show what we know. Hindsight is a wicked and ironic thing.
But it’s true. As Bluetooth-enabled devices become more prevalent, we are scrambling to learn more. Do you know what Bluetooth codecs are? And what do Bluetooth codecs do? Well, they are energy efficient, can reduce latency, and improve audio playback functions. Want to know more? Then keep reading…
What are Bluetooth Codecs?
Nearly all modern electronic communication devices have Bluetooth connectivity. We feel lost and unconnected without it. How would you enjoy a complete wireless headphones experience to the fullest degree without Bluetooth connections? You wouldn’t. Instead, you’d continue to be shackled to your phone by the ancient art of jack cording.
Don’t get it twisted (pun intended); many people still swear by jack connections and think Bluetooth is more hassle than fun. However, going wireless eliminates the need for jack connectors and frees up our surroundings. So, what are Bluetooth codecs for?
Start to understand Bluetooth codecs now…
The simple definition of Bluetooth codecs is an advanced audio codec algorithm. And that’s the simple definition. Codecs determine how Bluetooth is transmitted from a media device (laptop, PC, smartphones, etc.) to your Bluetooth-enabled device.
The codec encodes and decodes the digital audio data into a format to make it playable in your headphones. Codecs are essentially a way to transmit high-fidelity frequencies at a minimum bitrate. Before we go any further, we need to break down some of the technical jargon and terminology so we can explain Bluetooth codecs in more detail.
Bluetooth Codecs Terminology
There are a few important Bluetooth codec terms. Don’t let it bog you down too much, as you can crosscheck this section against the rest of the guide as you read through.
Sample Rates (Hz)
The sample rate is the number of data points per second that are in an audio file. If you want to capture the frequency, you will need to take two samples. These two samples will be gauged at -20Hz, which is double the limit of human hearing capabilities. If we are dealing in hi-res formats, they will be 96Hz or higher.
Bit depth (-bit)
If you add together all the bits in the audio sample, you can find the file’s resolution. To put this into perspective, a CD has 16-bit quality, while DVDs and Blu-ray discs are 24-bit. It’s very similar to the sample rate in regards to the higher bit-depth yielding larger files.
The bitrate is the number of processed bits per unit of time. This is usually measured in seconds. The main names for these are kilobits/second (kbps) or megabits per second (Mbps). Here’s how to calculate bitrate; sample rate TIMES bit-depth TIMES number of channels.
Bluetooth Transfer Rates – What are they, and what do they do?
Did you ever listen to your Bluetooth headphones when suddenly you lost connectivity? That’s because Bluetooth transfer rates are unstable. It’s why many audio geeks prefer wired headphones in terms of reliability.
If you ever brought a set of branded headphones from Sony or Philips, did you notice that they recommend a transfer rate for its codecs? However, it’s not usually a constant rate. It’s an optimal bitrate because your connectivity conditions constantly change. You will not be continually decoding at the optimal bitrate.
Keep within optimum connectivity range…
Bluetooth headphones and other devices have a connectivity range. Three to four meters is usually the average range for Bluetooth headphones. If you are not continually in the optimum connectivity range, you will not use your streaming speeds at maximum levels.
The further you move from the connectivity range, the more interference can derail your signal. People, walls, plants, air, and other resonant frequencies such as radio and WiFi all cause interference. Bluetooth codecs help to keep your headphones connected amidst a cacophony of frequencies.
Advanced Bluetooth Codecs Explained
The main goal of Bluetooth Codecs is to transmit hi-fidelity signals at a significantly lower bitrate. This will then free up lots of storage space, memory, and bandwidth. In essence, this helps simplify audio playback. These lower bitrates will affect audio quality, though. Greater compression of the file means less quality in terms of how it sounds.
If you are chilling at home and you want a quality music experience, less compression is the better choice. But if you are in traffic or busy at the gym, you can afford lower bitrates for your audio. Playback will improve, but the audio quality will decrease. With Bluetooth codecs, you can decide to favor audio quality over compression or vice versa.
Understanding Bluetooth Codec Frequency Bands
Now that we understand Bluetooth codecs in greater detail, it’s time to explore even more. Check out these varying Bluetooth codec frequency bands, what they do, and why they are important.
Low-complexity sub-band codec (SBC)
This low-complexity sub-band codec (SBC) is the lowest frequency Bluetooth codec of them all. This is the bare minimum requirement for the AD2P profile from the Bluetooth Special Interest Group. This determines how audio can be streamed between two devices.
The SBC band was originally used to stream audio quality at minimum bitrates. It’s simple and uncomplicated and was geared to support fluctuating Bluetooth bandwidth limits. The maximum transfer rate is 320kbps.
Qualcomm aptX, aptX HD, aptX adaptive, aptX LL
There is a multitude of varying Qualcomm codecs. Some of the most common Bluetooth codecs are aptX, aptX HD, aptX Adaptive, and aptX Low Latency (LL). If you are an avid Android user, these are the codecs that will most likely apply to you. If you have an iPhone, you will be best served using SBC. These Qualcomm codecs lesson stream latency.
If you are using a smartphone, there could be larger decreases depending on your phone model. If you are looking for a high-quality and accurate Bluetooth audio experience, buying headphones or earbuds that support aptX is essential. aptX supports 48Hz/16-bit LCPM audio data (352kbps). And aptX HD can handle 48Hz/24-bit LCPM audio data (576kpbs).
Advanced audio cooling (AAC)
Advanced Audio Cooling (AAC) is perfect for lossy digital audio compression. This is standardized across YouTube and PS4. It’s also a preference for Apple products. Don’t bother with AAC if you use an Android device. If you use an iPhone, you can benefit by utilizing these codecs for high-res playback.
This codec supports a transfer rate cap of 250kpbs.
Sony LDAC codecs
Did you know that Sony’s LDAC codecs, in theory, have transfers three times quicker than SBC? But in reality and practice, they are not that rapid. 990kpbs, 660kpbs, and 330kpbs are the three main LDAC modes.
The 990kpbs rate seems amazing, but in reality, phones usually have a 330kpbs default limit. So its bark is louder than its bite… rate. Do you see how we did that? The truth is that both SBC and aptX outperform LDAC in the two highest bitrate levels.
HWA Alliance’s LHDC & LLAC codecs
LHDC was originally designed by the Hi-Res Wireless Audio (HWA) Union and Savitech. The acronym stands for low-latency and high-definition audio codec. This powerful codec transfers three times faster than SBC and supports a maximum bitrate of 990kpbs.
The first smartphone to support these was the Huawei Mate 10. These low latency rates are ideal for gamers.
Bluetooth LE Audio LC3 codec
The Bluetooth LE Audio LC3 codec is a masterful codec that aids the deaf and hard-of-hearing. With this codec, you can connect hearing aids to stream audio. Talk about innovation. These codecs expand Bluetooth functionality, allowing a single source to stream to numerous Bluetooth devices at once.
Buying the Best Bluetooth-Enabled Codec Headphones
Now we understand more about Bluetooth codecs and how they simplify wireless connectivity, it’s time to research some products. Here is a handpicked selection of top-notch Bluetooth-enabled headphones with practical codec functions…
Need More Great Bluetooth Information and Products?
Our experts are here for you, so check out our helpful guides on Does Dolby Atmos Work with Bluetooth Headphones, Bluetooth Multipoint Explained, How to Reset Your Bluetooth Headphones, How to Fix Sound Delay in Bluetooth Headphones, Bluetooth Headphones Connected but Have No Sound for more useful information.
You might also like our detailed reviews of the Best Bluetooth Headphones for Conference Calls, the Best Wireless Bluetooth Headphones, the Best Bluetooth Headphones for Commuting, the Best Bluetooth Headphones Under $200, the Best Bluetooth Headphones Under $100, and the Best AptX Bluetooth Headphones currently available.
Understanding Bluetooth Codecs – Final thoughts
A complicated affair, indeed. But as Bluetooth-enabled headphones and speakers become more popular than ever before, the interest in codecs is also reaching a fever pitch. If you want total control over the frequency bands, understanding codecs are essential.
If you are consistently on the move but want to listen to audio wherever you go, using the correct codecs will make it possible. You will usually not be within the optimum range, so you need headphones with excellent codecs.
Until next time, happy listening.