What is FLAC? FLAC vs. MP3 Explained Simply


Image: Mike Wren (Adapted)

Ever go to download music and you are presented with the option to download the file in FLAC? Like many others out there, you may be thinking, what is FLAC and why is it so much larger than the MP3 file? A larger file size must mean better quality, right? In the case of FLAC, this holds true.

FLAC stands for Free Lossless Audio Codec, and in the interest of explaining FLAC vs. MP3 as succinctly as possible, we figured we would make 5 points to address the differences.

1) MP3 and FLAC Are both Audio Compression Formats

The audio that you end up downloading is not the original file that was recorded in the studio. If that was the case, you would have a gigantic audio file to download. What producers do is they take a mastered track and then compress the file into one of many file formats. In today’s world, MP3 is the most popular file format because it can compress rather large files into small sizes, while retaining most of its quality. FLAC does the same, except it is a lossless compression format, which is further explained below.

2) MP3 is Lossy while FLAC is Lossless

MP3 compresses audio quite efficiently. However, it is a lossy file format, which means that certain audio details get left out to reduce the file size substantially. That means very subtle details such as the third echo of a cymbal, or a faint whisper in the background of a quiet track. However, to most people these details are never even noticed, hence why the MP3 file format is so successful. It creates a small file size while retaining most of the important details.

FLAC on the other hand is a lossless file format. This means that while compressing the original audio recording, FLAC retains all of the original sound qualities, including that third cymbal echo and the faint whisper. This can make a substantial difference if you’re listening to music on an expensive headphone/amp setup.

3) FLAC to MP3 Makes Sense, MP3 to FLAC Never Makes Sense

The reason why converting from FLAC to MP3 makes sense, is because you are going from a high resolution source to a low resolution output. Think of it like going from an original photo to a very well-printed photocopy. The photocopy might lose some of the detail of the original image, but it will retain most of the detail. However, would you ever try making a photocopy an original photo? No.

Since MP3 is already a lossy file format, any detail that was lost in the original conversion to create the MP3 can never be retrieved. Thus, converting from MP3 to FLAC only increases file size, not quality.

4) FLAC Can Be a Better Choice vs. MP3 – Sometimes

Listening to a complex concerto that has an excellent dynamic range and hasn’t been enhanced to sound significantly louder? FLAC might be up your alley.

Listening to the latest pop song that was released for the radio and made to sound loud and fun? MP3 might be up your alley.

These two statements are not always true, obviously. There are pop songs that sound better in FLAC. But the key is: are there discernible differences in that recording? This is where the problem comes in with FLAC vs. MP3. Not all original recordings are high quality, while others are. For example, Daft Punk released their Deluxe Box Set Edition which includes a high-resolution 88.2 KHz / 24 bit copy of their album Random Access Memories. Knowing Daft Punk’s production quality, this is an example where pop music would certainly sound better on FLAC. Elliott Smith’s Either/Or album? Probably better for MP3 given that his intention was to sound low-fidelity.

5) FLAC is best on a high quality setup

Given that FLAC is retaining very subtle details that MP3 took out, you’ll need a good setup to maximize the benefits of FLAC. For starters, your headphones should be above average (i.e., Audio-Technica ATH-M50x and up), and you should have a somewhat decent DAC and amplifier (like the FiiO E10K) to allow the headphone to extract all that detail from your setup.

Even with all this said, FLAC can still be enjoyed on a simple phone-to-earbuds setup. The problem is that you’re going to have to deal with a file that’s anywhere from 2-3x larger than the MP3 counterpart, while not getting all of the benefits out of the file format.

So there you have it, FLAC vs. MP3 explained. While FLAC is not right for most users, we do like the movement towards lossless. It sets a higher standard for production companies, and it also sets a higher standard for most consumer’s ears. Which do you listen to? Let us know below.