Your Headphones' Greatest Enemy

Compressed Audio

by Kyle C
 
Working at Sound Lion has granted me an amazing opportunity to talk to hundreds of people about music, audio technology and of course headphones. It has also made me more aware of a problem that is becoming more and more rampant in the personal listening field. Most people aren’t aware that their music streams are compressed, and that they are degrading their experience and ultimately holding back the potential of their mobile devices.
Before I get into the specifics of the different music/media apps and their overall quality, let’s get a basis for what digital sound quality is, and what it really means to be low-fi. The most common format that you will find audio files from the web to be is MP3. This format tends to be very small in file size, and can have several different compression rates. The compression rate is measured in Kilobytes Per Second, or KBP/S. The higher the rate, the better the quality. For instance, a 256kbps track will sound significantly better than a 64kbps track. Any way you cut an MP3, the accuracy of it will never truly match the uncompressed formats, such as .wav or .flac . 

When a track is compressed, the compression algorithm chooses which data is needed and which is not. This loss of data is replaced by estimates made by the compression program, which means accuracy is lost. A low quality mp3 can be characterized by very tinny sound, cymbals and highs that sound distorted or crunchy. At a higher bit rate, such as 256kbps, this becomes much less noticeable, so try to keep your library’s average rate at a higher bit rate to improve your listening experience.


(Note that this is a very broad description, that individual tracks will sound better than others at specific compressions, and the above information is just to give you an idea of how it all works.)

When a customer walks into the store, the odds are they’ll gravitate towards the most intriguing pair they find and begin to search for music. We have iPads in the store with a library of tracks to listen to, but folks are much more inclined to play something from their own device. Being able to reference a song you know to judge the quality of the headphones can be very useful, so using your own library is always encouraged at Sound Lion.

Music & Media Apps

What I have realized from these encounters is that many music lovers aren’t giving themselves quality music! How do I know? Because the the first instinct for many customers is to open up YouTube or Pandora with the intent to judge the headphones' quality. It has become apparent that many people use music and media apps like these to get their music on the go, but if you’re investing in a quality pair of headphones it is nearly unjust to use some of these apps.
To put things into perspective: When someone uploads a song to YouTube, the odds are it will already be in compressed MP3 form. If the poster of the audio isn’t the actual record label, often the video won’t be in high definition, thus the sound quality suffers along with it. When the compressed MP3 is uploaded, it is compressed once more by YouTube (and the mobile version is the worst of it). If you are listening at home, then the following graph shows you the different selections of quality on a video and how the audio bitrate changes based on your choice.

Resolution	Audio Bit Rate	Compression
Original	152 kbps	AAC
1080p	152 kbps	AAC
720p	152 kbps	AAC
480p	128 kbps	AAC
360p	128 kbps	AAC
240p	60 kbps	MP3

(SOURCE: http://www.h3xed.com/web-and-internet/youtube-audio-quality-bitrate-240p-360p-480p-720p-1080p)

Many songs you will find were uploaded quite a while ago. If they are only available in 240p you can see (and hear) there is a serious degradation of quality as a whole. Even if you are playing the video just for the music, be sure to bump your quality up as high as it will go for the best experience. If possible though, avoid this venue all together and support your artists with a more accurate and reliable streaming service.

Another common customer interaction:
Me: “If you have your own music with you, you’re more than welcome to use that.”
Customer: “I don’t have any music on this phone, but sure, I’ll just play something on Pandora.”

Pandora can be a great service to learn new artists and tracks from the styles you love. The issue with this is that for someone who is not subscribed to the service the audio quality of each streamed track is 64kbps. As referenced before, this is much less than ideal, so if you enjoy the service and find yourself a frequent listener, you should really invest in a subscription for a higher quality sound. Spotify (another app which you can select specific tracks to listen to) streams to unsubscribed mobile devices at 96kpbs. While still a bit better than Pandora on this front, the subscription route will deliver you 320kpbs tracks which is very close to CD quality.

Home Library

If you’re backing up your CD library and you have the space to do it, compress at the highest bitrate you can to make sure you’re enjoying music the way it was intended by the artist. Personal listening can be one of the most powerful ways to experience your music, and doing your speakers or headphones justice will make your overall happiness with what you’re hearing skyrocket. Be aware that although convenient, streaming music will usually not be as accurate as the real CD, unless you pony up for the subscription plans. YouTube or Spotify can be good in a pinch, but if you’re a consistent music listener your best experience will not be found in compressed audio, period.



I don’t knock anyone for using any of these apps, of course. they are all quick and easy solutions to get music, and sometimes when you need a specific track that is the only method available to you. However, when you’re looking to make a purchase, or really just test out any type of speaker, try your best to avoid these forums. A high fidelity device needs high fidelity signal to properly perform! If you’re ever curious about the nitty-gritty of compression or want to hear the difference for yourself, come into the store and I’ll be happy to give you a demo.