MP3s are a compression audio format that rose to prominence in the late 90s and early 2000s. Our appetites for music and convenience far exceeded the storage capacity of most devices at the time. MP3s provided a way to store hundreds of songs on small hard drives or multimedia players. Most of the younger generations have spent their lives listening to MP3s and rarely hear CDs or other high-quality audio formats. 

MP3 compression throws away information it deems unnecessary to the human listening experience and clips notes on the extreme range. MP3s under 128 kbps are going to have noticeable sound degradation. Your brain has to work harder to listen to the degraded sound, meaning MP3s can be quite draining. When possible, choose higher-quality audio formats, like FLAC, WMA, and ALAC, to have a more enjoyable listening experience that won’t make you feel bad. 

MP3s are a type of audio file that has been compressed using an algorithm. MP3 stands for MPEG-1 Audio Layer 3. MP3s were created by the Fraunhofer Institute in Germany. MP3s were then released as one of MPEG1’s three schemes, by the Moving Picture Experts Group (MPEG), in 1993. A year later MPEG2 was released with more audio channels and bit rates.

MP3s were widely adopted because of the impressive reduction in audio file size, which could easily be created from free computer programs. MP3 encoders and rippers started emerging in the mid-1990s. Fraunhofer exercised their MP3 patent rights, requiring developers of encoders and rippers to pay them a licensing fee. 

Before MP3s

CDs, the first digital data storage technology for audio, were the reigning format for playing music before MP3s took over. CDs themselves replaced outdated analog cassettes in the late 80s and early 90s. With compact discs, the audio is stored as microscopic bumps in a long spiral of data. CDs were revolutionary in their time for their storage capacity, about 70 MiB or 80 minutes of audio. The majority of computer hard drives had less storage capacity at the time. 

While CDs store high-quality audio in a compact digital format, they aren’t ideal. CDs were still physical disks that had to be stored and handled with care. Compact discs are very susceptible to damage, such as scratches and pitting on the polycarbonate plastic surface. 

MP3s replaced CDs not because of an improved listening experience, but because they take up much less space and therefore you can have more. Plus you can keep them stored digitally on your computer, instead of needing to insert a CD. Early adopters of MP3s were less concerned about audio quality and more about the ‘coolness’ of having hundreds of MP3s available on their computer or MP3 player for listening on demand.  

Audio Compression

Digital audio is simply audio that has been translated into digital information. When audio is recorded, it is uncompressed (also known as lossless). The audio is recorded to the highest data resolution that the audio equipment can detect. The industry-standard sample rate is 44,100 Hz, meaning the audio is captured 44,100 times per second. 

Another component of recorded audio is the bit depth, which is the number of values the sample can fall within. Think of it as the sample range. Pristine audio has a bit depth of 32 bits, but 16 bits is often usually acceptable. High-quality audio files quickly grow too large to be easily shared and stored en masse. 

Audio can be compressed purposefully, by an audio engineer, to produce a better quality track with more balance and polish. Compression can lower the peaks in audio files, to more accurately capture the quiet and louder extremes. A professionally compressed audio file makes for a more comfortable listening experience. 

The best uncompressed audio formats are WAV and AIFF. WAV is typically used on Windows systems and AIFF is mostly for Macs. If you have a library of WAV or AIFF music, your music collection will take up a lot of space but will sound great. 

Types of Compression

For the purposes of this article, we’re concerned with audio compression that does not improve the overall audio product. MP3 compression algorithms range from 96 to 320Kbps. More specifically, MP3 compression uses psychoacoustic lossy compression. 

Lossy Compression

The primary goal of lossy compression is to reduce the file size. With lossy compression you are losing pieces of information, tossing them out because they are deemed unnecessary or duplicates. Lossy compression is irreversible. Once the extra data has been stripped, it cannot be restored. You must keep the original audio file if you ever need the higher quality. 

So what is the psychoacoustic component of MP3 compression? Well in order to make the best sounding compressed MP3, psychoacoustic models identify and remove the audio components that are unnecessary and won’t be missed or noticed by human hearing. Humans cannot perceive frequencies outside of the 20 Hz to 20 kHz range in most instances, so these are frequencies are removed.  

AAC is another lossy compression format. If you listen to music on Spotify you may be surprised to learn that your audio is streaming using a lossy format called Ogg Vorbis at 320Kbps. Yet Spotify is promising to release Spotify HiFi, a lossless tier, sometime in 2022. 

Lossless Compression

Lossless compression can compress audio files without removing any information. Lossless compression formats include FLAC, WMA, and ALAC. Lossless compressed formats are highly preferred these days, with higher quality but still being compressed enough to aid data storage. 

Lossless compression maintains audio integrity while reducing file size, by simply shrinking the file. Think of it like a ZIP or RAR file, but for an audio file. 

Don’t confuse lossless compression with lossless. Lossless audio files are original uncompressed audio files. If you want to listen to lossless audio on the go, select streaming services like Apple Music, TIDAL, Qobuz, or Deezer.

How do MP3s Sound?

So why do we care about how MP3s are compressed? Well, it turns out all this lossy compression makes the MP3 audio sounds very bad. If you can’t compare to an uncompressed audio file or don’t have an ear trained to high-quality audio, you might not even recognize the things that make MP3s sound bad. 

When MP3s are compressed and encoded, artifacts are inserted or left behind. These artifacts add noise, usually unpleasant, to the listening experience. You might hear it as a sizzling or metallic swirling sound. 

MP3 encoders lack the headroom to accommodate the peaks capable on CDs, introducing a familiar sizzle. For example, when the drums and singer are acting together, the audio peaks past the MP3 encoder headroom. This part of the audio will be clipped and sound like a flat sizzle. Once you have it pointed out once, you’ll hear it everywhere. 

How do MP3s Make You Feel?

Younger generations have spent their lives listening to MP3s and streaming audio. These lower-quality audio files are all they know. Professor Johnathan Burger claims that his students prefer the MP3 sizzle over high-quality lossless formats more each year. But research suggests that MP3 audio induces emotional changes and makes you feel bad.

Each musical instrument has a unique sound, with characteristics that evoke emotions. Music can convey any emotion, from melancholy or mad to happiness and excitement. According to research, listening to MP3 compression reduces the positive emotional characteristics of audio, while increasing the negative emotional characteristics. Because of music’s relatively calming or sedating effect, anger is not increased by compression, but sadness, shyness, and scariness are. 

Plus, compressed MP3 audio is not natural to your brain. Listening to music is supposed to be effortless, our ears are designed to interpret real high-fidelity sounds. If you compare a week of listening to high-quality audio, like a lossless compression format, then a week listening to strictly MP3s, your brain will feel significantly more fatigued during the second week. You may even feel nauseous or melancholy.

Wrapping up MP3 Compression

At the end of the day, many people choose convenience over quality. That’s the story behind the success of the MP3. MP3 compression algorithms strip all of the peaks from the original file, while also removing frequencies you can’t hear. But your brain can tell the difference. Listening to the compressed MP3 format can induce a negative emotional shift in your brain. You will feel negative emotions more strongly, while positive emotions are subdued, the exact opposite of what you want when listening to music. 

If you want to enjoy the benefits of music, like reduced stress and increased happiness, it’s time to ditch MP3s. Keep streaming music, but choose a lossless service like Apple Music or TIDAL to get the best experience. With today’s storage capabilities you can even keep your favorite tunes available on your phone or computer, using one of the high-quality uncompressed audio formats.

…are those MP3s still in the room with you?