You may have come across the term “audio bitrate” on streaming or downloading services, but maybe you aren’t completely sure what the term means. In this article, we will explore exactly what audio bitrate is and why it matters as a DJ or producer.
What is Audio Bitrate?
Audio bitrate is the amount of data (or bits) that are processed in a certain amount of time. The most common way to measure bitrate is in kilobits per second. When you download a track off Beatport, the MP3 will be in 320kbps. This means the track has 320 kilobits per second of audio. Comparatively, when you buy a track from iTunes, it comes at 256 kbps. This kbps is just slightly lower, and it comes with a slight loss of quality. If you’re ripping tracks off Youtube, for example, the sound quality of 128kpbs is really low. If you were ever to play that track in a live setting, it would be quite noticeable. The loss of quality would definitely stand out to the crowd. I highly suggest avoiding taking tracks from Youtube; you should be supporting fellow artists and purchasing higher quality music at the same time.
A Brief History of Sound Files
Before we talk about WAV and AIFF files let’s go back to the 1990s, when we all were walking around with CD players or walkmans. Shortly after came MP3s. Instead of carrying around a brick for cassettes, or a plate for CD’s you could now store thirty or so songs on one little stick. I think my first MP3 player had around 128 megabytes.
So how did we get so many more songs in a much smaller amount of space? The way to achieve this was to compress the audio files into a smaller size. CD’s could hold around 700 megabytes, which was about 80 minutes of high-quality music. An MP3 player that was 512 megabytes could hold about double the amount of songs and was much smaller to carry around. The loss of sound quality didn’t seem to bother most people, so MP3s grew in popularity. This paved the way for new technology like iPods and music players on cell phones. Today, MP3 remains popular with streaming services like Spotify and Apple Music.
Finally, we have our uncompressed audio quality files: WAV and AIFF. WAV format was created by Microsoft and AIFF was created by Apple. These file types are not compressed and are therefore the largest audio file sizes. There are also lossless compressed audio formats, which means the file is compressed but the quality can be perfectly reconstructed from the compressed data.
What's the Difference Between Audio File Types?
A lot of people argue that the sound quality difference between these file types is very noticeable. According to them, uncompressed audio formats are the only way to go for the highest quality of sound. Personally, I don’t agree. The majority of people listening to music today are less concerned with the quality of music as they are with the number of songs they can have or stream. The difference between a 320MP3 and WAV is a big jump in file size, which means each file takes up significantly more space. The majority of casual listeners using their personal devices such as laptops, speakers, or wireless headphones won’t notice the difference in sound quality anyway.
If you are someone who cares about high-quality audio then chances are you’ll know enough to buy or stream from high-quality services. As producers, we all appreciate high-quality audio. Keep in mind, however, that the majority of music fans are average listeners who will not be able to tell the difference. Sound quality is definitely something to be aware of and understand, but you shouldn’t worry too much about it when delivering your content commercially. The commercial standard today is still MP3, but if you’d like to also provide an uncompressed version of your music – the option is there. If you’re signing your tracks to Beatport, for example, your buyers have the option to upgrade their purchase to WAV or AIFF format.
What is Bit Depth?
Bit depth in an audio engineering standpoint. When recording audio, recording in a higher bit depth gives you a more dynamic range between your recording and the noise floor.
In basic terms, the noise floor is the atmospheric or digitally created sound through the electronics and gear of your equipment. A higher bit depth gives engineers a more dynamic range or volume from the noise floor to work with when recording. A 16-bit depth rate has a signal to noise ratio of 96 dB, whereas a 24-bit depth rate has 144 dB.
If you use compressors and limiters, you will be turning up the volume of the undesired sounds from the noise floor, etc. But with a higher bit rate depth and more dynamic range, engineers have more range to avoid hearing the background noise.
Producers don’t need to focus on this as much, because we don’t have to worry about the noise floor with internal sound design. Since most of our sounds are digitally created, we don’t have to worry about atmospheric sounds or background noise coming from our gear.
What Bit Depth Should You Use?
Most mastering engineers will ask for either 16bit or 24bit WAV files for their pre-masters. When exporting the final versions of your tracks, 16bit WAV is fine for commercial use. For more professional use, I would suggest exporting in 24bit. Chances are that for commercial use, it’s going to be 16bit anyways.
What About Sample Rate?
Sample rate is fairly easy to understand. It refers to the number of samples of audio carried per second and is measured in Hz or kHz. In other words, sample rate is how fast samples are written and played. For example, CD’s and commercial music usually run at 44.1Khz, which gives us a frequency range of up to about 22Khz. Since humans can only hear up to 20khz at best, there isn’t really a reason to be pushing for a higher sample rate. Movie production or really high-quality processing might call for higher sample rates, but it’s not really beneficial for average consumers.
Bit rate and bit depth can be confusing to understand at first, but hopefully this article helped to clear up some confusion you may have had. The most important thing to remember is to not stress too much over the file quality of your music. Following the industry standard of MP3 at 320kbps is usually a safe bet!
For further information, check out my music production courses! I go over a bit rate and bit depth in greater detail.