Cracking the Codec: What is the Best Audio Format?

Digital audio is the core of the modern music industry. From the music you stream on your phone to the actual master tracks that are recorded in the studio, almost all of the music you listen to has at one point been an audio file.

As it was with wax cylinders, vinyl records and cassette tapes, digital audio files are packaged in one of many different audio formats. And as people who care about getting the best audio quality, this begs the question: which audio format is the best for sound quality?

If you want the short and simple answer, it’s WAV or AIFF — both formats store uncompressed audio in the same specifications used in basically the entire music industry. 

But as with a lot of things in the audiophile space, there’s always the prospect of “more” in the pursuit of “better sound quality”. So in this guide, we’ll go through the basics of these audio formats, which ones you should care about, and why it’s okay to ignore the rest. 

What Is An Audio Format?

An audio format, in its simplest form, is just the way we store an audio recording. As we touched on at the beginning of the article everything from cassette tapes to vinyl records are audio formats.

A digital audio format is just that but stored as data that we can put on a CD in our phones or on a big data server to stream over the internet.

When talking about digital audio formats, you might see some people use the terms “audio format” and “audio codec” interchangeably. While this isn’t quite accurate, most uses of these terms do talk about more or less the same thing — it’s a stream of data that’s translated by a digital audio player to play as sound through your headphones and speakers. 

The main difference between the two terms lies in what part of that code the term is referring to. An audio format is the code that determines how audio data is stored in code, whether it is done with or without compression.

An audio codec (short for coder-decoder), meanwhile, refers to the software that translates audio data into the format of choice.

These formats can be put into three groups: uncompressed formats, lossy formats, and lossless formats.

1. Uncompressed Formats

An uncompressed format, as the name suggests, stores all of the data of the recording without any compression applied to it. 

There are two examples of this in common circulation:

• WAV (Waveform Audio File Format), a format developed by IBM and Microsoft for storing computer audio; is also commonly used as the standard format for converting Red Book audio CDs into audio files. 
• AIFF (Audio Interchange File Format), was developed by Apple for use on their Macintosh computers. Also used at some point for Commodore Amiga systems. It’s also the format iTunes uses when you import CD audio into audio files on MacOS.

Being uncompressed means that you retain absolutely all of the details from the recording, and as such are considered to have the “best sound quality” because of this. The catch is that a WAV or AIFF file encodes everything — including silence — at the same data rate (or “bit rate”) as it would when the file actually does contain music. This, of course, means a pretty big file size.

On average, a WAV file based on the standard CD Red Book specification (16-bit depth, 44.1 kHz sample rate) would take up to 10 MB per minute of audio.

2. Lossy Formats

A lossy format, meanwhile, is quite a bit smaller — taking up to 3 MB of storage space per minute of audio. It’s this reduction in file size that makes these lossy formats very useful and popular in the Internet age. 

Some of the most common formats you’ll find include:

• MP3 (MPEG Layer-3), is by far the most popular lossy audio format out there. Used most commonly in online distribution and as digital downloads for most music nowadays.
• AAC (Advanced Audio Coding), a lossy format developed as a successor to the MP3 standard. Its improved algorithm allows it to capture more of the original data compared to MP3 at the same bit rate (therefore giving it better sound quality) but is less commonly seen because of patent and licensing concerns as well as MP3 being already very well-established and supported by basically anything that can play audio.

AAC is still in fairly widespread use, though. It’s mainly known as the format used to store audio in MP4 video files, as well as the audio format used on Apple Music and the iTunes Store. 

• Ogg Vorbis is an audio format whose main features are great audio quality at lower bit rates compared to MP3 and an open-source license (which for the most part just means no licensing fees). These two qualities make them especially popular for storing audio in video games, such as sound effects and background music.

But how do these formats save so much space? 

It comes down to a lot of compression. Lossy formats are named such because they use lossy compression algorithms, which approximate and simplify data in very clever ways to make a file much smaller than it originally was.

However, lossy compression methods do discard some data during the compression process, which means that audio files in these formats don’t have all of the details of the original recording. As you can imagine, this doesn’t align with the audiophile ideal of maximizing sound quality—so what does?

3. Lossless Formats

This brings us to lossless audio formats, of which there are two in common circulation: FLAC (Free Lossless Audio Codec) and ALAC (Apple Lossless Audio Codec). As the name suggests, these formats use lossless compression methods when converting audio into this format.

Unlike lossy compression, though, lossless compression does not discard any of the original data from the recording, ensuring that a lossless audio file is practically identical to the uncompressed source while also being at a smaller file size. 

Naturally, the file size also ends up being larger than a  lossy format — usually around 5 to 6 MB per minute of audio.

But a size reduction of nearly half compared to an uncompressed file adds up very quickly, and if you’re the kind who hoards dozens of albums, then you will definitely notice the difference in size but not any change in sound quality.

The Best Audio Format — And Why It Isn’t Used Everywhere

With everything that we discussed so far, it seems like the obvious answer for “what is the best audio format” is a lossless format like FLAC or ALAC. A lossless audio file is significantly smaller than an uncompressed file like WAV while also keeping all of the original audio data for the best sound quality. 

By all accounts, they should be the best. So why are MP3s still the most widely used audio format out there?

Besides the obvious answer of people being resistant to change and MP3 already being the popular and well-established format for well over two decades now, we think it comes down to two main factors: data usage and perceived sound quality.

Data Usage

At the time of writing this guide, a typical solid-state drive with 1TB of space (that’s about 1,000,000 MB, give or take) costs about $50. If you buy a hard disk drive, that price can drop down to $40 or even less depending on where you look.

Even smartphone storage has gotten a lot bigger over time, with 128 GB of onboard storage being fairly common among even low-end phones. 

In any case, the takeaway here is that the cost of storage has dropped quite a bit over the last couple of decades. As such, it’s become much easier for us to store music in larger, higher-quality formats like FLAC.

But while storing music is pretty cheap nowadays, the data plan you usually use for streaming isn’t.

Now, if you’re the kind of person who has their entire music collection stored in all of their devices, this won’t really affect you. But for the vast majority of people who use streaming services like Spotify or Apple Music, the choice to use lossy music files isn’t entirely unreasonable. 

Sure, lossless streaming services do exist now. Deezer and Tidal are the most well-known, although Apple Music has also started rolling out lossless streaming as of 2021. But try to stream lossless music over a weak internet connection or data plan, and you’ll see that choosing lossless doesn’t really work out.

Perceived Audio Quality

One of the big reasons why lossy audio formats like MP3 and AAC are still so widely used is that, for the most part, they don’t actually sound worse than their lossless or uncompressed counterparts. 

In fact, it’s extremely difficult to even tell the difference between a lossless file and a 320 kbps MP3 file.

A lot of formal and informal studies over the years have actually looked into this and found that even trained listeners or audiophiles have a hard time telling the difference between a 320 kbps MP3 file (the standard for most digital music downloads and streaming services) and a lossless file.

And that’s before we consider the other parts of the audio chain. 

As we know, your audio quality can only be as good as its weakest link. Even if you did have lossless streaming and great headphones, that gets hampered if you have to stream music to your headphones over Bluetooth.

And even if you worked out all of the kinks and put together the best audio setup in the world, there could be a problem with the mastering of the music itself. 

Conclusion

As with a lot of things in the audiophile space, nothing is definitive — the audio format of the music you listen to is one of them. 

While uncompressed files like WAV and lossless files like FLAC are by far the best audio formats for sound quality, there are times when they can be inconvenient.

But that doesn’t mean you should discount MP3s just because they don’t have that last 1% or 2% of audio data that was discarded during compression. There are so many parts of your audiophile setup that are bigger things to worry about if you’re chasing after a better listening experience.

The bottom line is if you’re enjoying the music, it really doesn’t matter what file format it’s in.