Bluetooth devices use audio codecs to transmit audio signals over a wireless connection. The codecs feature compression algorithms that help to reduce file sizes, allowing them to be transmitted wirelessly over a Bluetooth connection.
Different Bluetooth codecs have different compression rates, which affects the quality of the audio that is transmitted. Some codecs prioritize audio quality over file size, while others prioritize smaller file sizes over audio quality. Ideally, when choosing a Bluetooth codec, it’s important to consider the devices you’re using and the type of audio you’ll be transmitting.
Some of the most common Bluetooth codecs are SBC (Sub-Band Coding) and AAC (Advanced Audio Codec). SBC is the most basic codec, and is used in almost all Bluetooth devices. On the other hand, AAC is a higher-quality codec, commonly used in Apple devices.
In today’s article, we’ll take a look at the technology behind these two wireless audio codecs and see how they compare and contrast. Read on!
SBC vs AAC – Quick Comparison
| SBC | AAC | |
| Bit rate | Up to 328kbps | Up to 320kbps |
| Bit depth | 16-bit | 24-bit |
| Sampling rate | Up to 48kHz | Up to 44.1kHz |
| Latency | High latency | Low latency |
| Compatibility | Universal compatibility | Limited compatibility |
AAC Overview
AAC is a Bluetooth codec that is used widely in Apple products. It provides high-quality audio with a higher bit rate, which means that it can stream high-quality audio without using too much bandwidth. It also has a low latency, which means there is little delay between when the audio is played and when it is received.
When using Apple headphones or wireless speakers, the audio data is compressed using the AAC codec before being transmitted over the Bluetooth connection. The receiver then decompresses the audio data using the same codec to play it back.
Ideally, AAC supports a wider frequency range than SBC, which means it can capture more of the nuances of the original audio. That’s not all. AAC is also one of the best file formats for storing music on Apple and other music devices.
Advantages of AAC
- High audio quality-AAC provides high-quality audio encoding and decoding with minimal loss of audio fidelity, making it a good choice for high-quality wireless audio streaming. AAC is capable of producing high-quality audio at lower bitrates, which is important for streaming music over Bluetooth.
- Low latency- AAC has low latency, which means that audio data can be transmitted quickly, resulting in a better audio streaming experience with fewer delays or sync issues. This makes it ideal for real-time audio applications, such as gaming and video conferencing.
- Efficient compression- AAC is an efficient audio compression format, meaning that it can reduce the size of audio files without compromising audio quality.
- Power efficiency- As we have stated, AAC is a highly efficient codec that can compress audio files without sacrificing sound quality. This means that it uses less bandwidth and requires less processing power, which is important for mobile devices that have limited battery life.
Disadvantages of AAC
- Limited compatibility- Although AAC is widely supported, it may not be supported by some older devices or operating systems. This might limit its compatibility with certain devices.
- Higher power consumption- Using the AAC codec for Bluetooth audio streaming may consume more power than SBC, which could impact battery life on portable devices.
- Limited bitrate support- The AAC codec has a limited range of supported bitrates, which could limit the quality of audio streaming or file compression.
- Licensing fees- AAC is a proprietary codec, which means that it requires licensing fees to use. This might increase the cost of devices that support it.
What is SBC?
SBC is a basic codec that is used in most Bluetooth devices. It is a mandatory codec for Bluetooth audio devices and is supported by virtually all Bluetooth-enabled devices, including smartphones, laptops, headphones, and speakers.
As the name suggests, SBC works by dividing the audio signal into multiple subbands, which are then separately encoded and transmitted over Bluetooth. The codec is also designed to adjust the number of subbands used based on the bandwidth available, which helps to optimize audio quality based on the capabilities of the transmitting and receiving devices.
Generally, SBC has a higher bit rate than a standard Bluetooth connection, which means it can transmit more data and potentially provide better sound quality. However, it also has a higher latency and a narrower frequency range than its AAC counterpart. This means that the audio may be delayed, and some of the nuances of the original audio may be lost.
Advantages of SBC
- Universal compatibility- Most modern Bluetooth devices, including smartphones, tablets, and laptops, support the SBC codec as it is a mandatory codec for Bluetooth audio. However, some newer Bluetooth headphones and speakers support more advanced codecs like aptX, AAC, or LDAC, which offer higher-quality audio compared to SBC.
- Low power consumption- SBC has a low bitrate compared to other AAC, which makes it a more power-efficient option for wireless audio transmission. This is particularly important for mobile devices like smartphones and headphones, where battery life is a major concern.
- Variable bitrate- SBC uses a variable bitrate to compress audio data, which means that the amount of data used to represent audio can vary depending on the complexity of the audio being transmitted. This means that SBC can provide good audio quality even in situations where bandwidth is limited.
- Dual- channel support- SBC supports dual-channel audio, which means it can transmit audio signals to two separate channels simultaneously. This is important for stereo audio playback, where separate audio signals are sent to the left and right channels.
- Low complexity- SBC is a low-complexity codec, which means it is simple to implement and doesn’t require a lot of processing power. This makes it an ideal choice for devices with limited processing capabilities, such as smartphones and wireless earbuds.
Disadvantages of SBC
- Limited audio quality- Although SBC is a widely used codec, it has some limitations when it comes to audio quality. It is a lossy codec, meaning that some audio data is lost during compression, which can result in a reduction in audio quality.
- Lower bitrate- The bitrate of SBC is not very high compared to AAC, which means that it may not provide the best audio quality. This can be a problem for audiophiles or people who are particular about the quality of their audio.
- Compression artifacts- SBC uses a compression algorithm that can introduce compression artifacts into the audio signal. These artifacts can be audible as distortion or noise in the audio signal.
- Poor performance at high bitrates- SBC may not perform as well at high bitrates, which can result in further degradation of audio quality.
AAC vs SBC- Which is Superior?
As we have mentioned, AAC and SBC are two of the most common codecs used for streaming audio over Bluetooth. However, in terms of AAC is generally considered superior to SBC, as it provides better audio quality at lower bitrates. However, the quality of audio depends on several factors, such as the source material, the quality of the headphones or speakers, and the Bluetooth device’s quality.
AAC is also considered to be a superior codec compared to SBC because of its lower latency, wider frequency range, and higher compression efficiency. Overall, if your Bluetooth device supports AAC, it is recommended to use it over SBC for better audio quality. However, if your device does not support AAC, SBC is a reliable fallback option.
While SBC may not offer the highest audio quality of all the available Bluetooth audio codecs, its universal compatibility, low power consumption, and variable bitrate make it a popular and reliable choice for wireless audio transmission. It’s also worth noting that not all Bluetooth devices support AAC, so SBC may be the only option available in some cases.
SBC is a more widely supported codec than AAC. SBC is a mandatory codec for the Bluetooth A2DP profile, which means that all Bluetooth devices that support A2DP must support SBC. AAC, on the other hand, is an optional codec for A2DP, so not all devices support it.
Overall, both AAC and SBC have their advantages and disadvantages, and the choice between the two will depend on factors such as the desired sound quality, latency requirements, device compatibility, and power consumption.
If you’re looking for high-quality sound, low latency, and have a device that supports it, then AAC may be the better choice. However, if battery life is a concern or you want a more widely compatible codec, then SBC may be the better choice.
We hope you found this comparison helpful. Please share your thoughts in the comments section below!
