Historically, the most successful music streaming services have operated using two key formats: MP3 and AAC. Both formats take audio data and compress it by removing parts of the information deemed irrelevant to the listening experience.
This type of compression is referred to as “lossy,” and comes in a variety of bit rates. These bit rates determine how much audio data is removed, and the size of the file itself following compression.
Standard File Sizes (3-minute song):
- CD-Quality WAV file (uncompressed): 31.7 MB
- CD-Quality FLAC file (compressed): 15.85 MB
- 320 kbps MP3: 7.2 MB
- 256 kbps AAC: 5.76 MB
- 192 kbps MP3: 4.32 MB
- 128 kbps MP3: 2.88 MB
Even the highest bit rate (320 kbps) lossy compression reduces a song to 1/4 of its original size. This opens a world of possibilities for on-demand music services to deliver “near-CD” quality at tremendously faster speeds. Apple’s iTunes has sold (and now streamed via Apple Music) 256 kbps AAC files since 2011, and Spotify has offered 320 kbps mobile streaming since 2012.
What changed? Why did people suddenly start craving mobile high-definition music?
Lossless audio encoding like FLAC and Apple Lossless have existed for a long time. Lossless compression is a class of data compression algorithmsthat allows the original data to be perfectly represented by compressed data. Sophisticated algorithms create a file that sounds mathematically identical, at 50–60% the original size.
Pretty cool, right? Get original master recording sound quality at half the size. On hi-fi audio equipment, there is no doubt that lossless audio is fuller, richer, and more faithful than MP3 or AAC. It seems like anyone would want lossless audio, but as with all data — the devil is in the details. Size really does matter, and so do the people on the other end of the stream.
Bigger Isn’t Always Better
The MediaNet catalog contains 42 million tracks in 12 different formats.Let’s pretend for a moment that we only carry 320 kbps MP3, and every track is 3 minutes long. Storing this imaginary catalog would require 298,200,000 megabytes, or 298.2 terabytes, of usable server space.
Compare that with a 42 million track library of FLAC files, which would require 665,700,000 megabytes, or 665.7 terabytes, of usable server space. That’s 223% more space than the highest-quality MP3 library to store, and it isn’t taking into account the metadata contained in the files (ISRC, track name, artist, album, release year, etc).
Lossless audio requires 223% more storage space than high-quality MP3
Even today, server space isn’t particularly cheap. Using Amazon Web Services’ S3 Enterprise Cloud Storage solution, our FLAC library would cost $20,900 each month. Simply to store the files. Compare this with the relatively low cost of MP3 at $9,500, and you can begin to see the problem.
Then add the cost of delivering those files to users. A standard streaming service can easily log over 500,000,000 plays in one month. That means our FLAC catalog would deliver 7.9 petabytes of data to users vs 3.6 petabytes for MP3, every single month. $426,900 vs. $204,300, respectively. That’s 209% more per month to deliver FLAC audio instead of MP3.
In reality, the cost of delivering digital audio could be slightly higher or lower, but can generally be accepted as increasing proportionally with file size. At over double the cost, lossless audio files are a huge strain on storage and bandwidth, as well as existing server architecture.
Many streaming services, especially those just launching, can’t afford that huge infrastructure cost without massive investment.
Your iPhone Will Hate You
So what? Lossless streaming services like TIDAL, Qobuz, and Deezer Elite have found a way to afford the massive infrastructure costs. Why can’t everyone else? The next sticking point is how a service’s music is consumed.
52% of Spotify users consume their music on a mobile device such as a phone or tablet. This means that data throughput is subject to an individual’s mobile data plan.
Verizon’s “More Everything” plan offers users 10 GB of data per month.According to Pew Research, half of all cell phone users listen to mobile music. Let’s assume 50% of their data (5 GB) is available for music streaming.
“Few people really want to pay more to wireless carriers for any data overage charges associated with streaming high-quality music.” — Venture Beat
Using a FLAC streaming service, a user could listen to roughly 315 songs per month, or 10 songs per day. Using an MP3 streaming service, a user could listen to roughly 694 songs per month, or 22 songs per day. That huge discrepancy could cost consumers tens or hundreds of dollars in data overage charges. That’s bad PR.
These numbers don’t take into account the elements of the user interface (album art, UI elements, etc) that are loaded each play. Existing apps must also be re-built with enhanced delivery APIs required to stream lossless audio. All these factors equal a huge strain on a user’s data bandwidth.
Even More Technology Costs
Did you know that codecs like MP3, AAC, and others cost money to use? Every streaming service has to pay a license fee (either one-time or per-play) to the technology company that created the codec. While FLAC is truly free, many other lossless codecs are not.
This problem is compounded when attempting to get permission from a record label to offer music in a lossless format. Labels are understandably protective of their 24-bit masters, as they are a great way to establish copyright. As the gatekeepers of high-definition content, labels are choosy with who they allow to stream content beyond 320 kbps MP3.
Additionally, finding the studio-quality digital masters for every single track you want in your catalog can be difficult when you’re dealing with over 370,000 labels and 500,000 new tracks released each month. (That’s what we handle at MediaNet for our catalog.)
Labels don’t offer a “better than CD” experience to just anyone, and if a service is deemed worthy of lossless audio, it may be required to use certain codecs, licensors, and B2B partners approved by the label. These may not be the same for each label. Each of those partnerships can require additional license fees.
You Probably Won’t Hear The Difference Anyway
When it’s all said and done, is high-definition audio really any better than high-quality MP3? It depends on who you are and how you’re listening.
NPR and The Verge both put that question to the test: Can you tell the difference between AAC, MP3, and FLAC? NPR claims “many listeners cannot hear the difference,” and The Verge found that in “29 percent of the tests, subjects couldn’t tell any notable difference at all.”
29% of people can’t tell any difference between lossless and MP3 audio
While lossless audio might seem like the next frontier in digital audio, it faces an uphill battle: it’s too expensive to do at the same price as MP3. Until server and bandwidth costs decrease significantly, high-definition streaming audio will always be a boutique market.
All things being equal, lossless audio sounds better than lossy audio. It’s simple mathematics. But imagine you’re on the train, at rush hour, listening to music on non-isolated earbuds while conversations are happening 2 feet from your ears. Without a dedicated hi-fi like SONOS or Cambridge Audio, will you really be able to hear the subtle differences in Coltrane’s tenor sax?
Most streaming services aren’t going to invest 223% more to find out.