Does Dropbox compress audio?

[jsdigital]

Hey dude, you ever get an answer on this? This really concerns me because I use Dropbox to back up all my Logic Pro projects and their source audio files.

[Jay · Accepted solution]

Hi @jsdigital, welcome to the forums!

I’ve moved your post since the previous one was quite old!

Regarding your query, Dropbox doesn’t modify your files in any way. However, there are very rare circumstances when a file can be ‘changed’ in some manner, though this is unrelated to Dropbox.

The first, and ‘most common’ is a third party app is affecting the file. This could be that a virus scanner is checking the file, and yet affects the original. Maybe on the originator’s end there was a similar issues, it’s hard to tell.

Another, albeit rare possibility, is that downloading through the browser itself could be the issue. While Dropbox can preview WAV files, it is subject to the limitations of the browser, likewise with downloading them. Again, this is very rare, but can happen.

Overall, in answer to your question, we’ve had many users sync high quality, uncompressed files, WAV, FLAC, APE etc, and none have experienced any issues. For those users that did experience some form of compression, corruption, or other matter, then it was usually due to an interrupted upload/download, poor encoding to begin with, or even not have the correct codec to play the file at the destination. 

Even WAV files have codecs on how it reads the uncompressed music!

Hopefully this should clarify matters for you, however if you have any questions, feel free to let me know!

[jsdigital]

Great insights. Thanks so much Jay, this is super helpful.

[madtheory]

Actually it's not the browser. The Dropbox media player itself is transcoding the original audio when you preview it in any browser. This is referenced here (search in page for "Transcoding"):
https://www.dropbox.com/help/files-folders/preview

For example right now I'm playing back a 320k MP3 file. It sounds different when streamed in the browser compared to off the synced folder on my computer. From the browser it has all of the hallmarks of 128k MP3 transcoding. The hi hats sound like there's a flanger on them and overall the track is duller when streamed in the browser. This is in Chrome on Mac.

But your original file does not get changed- this is only when previewing with Dropbox app on a smartphone, or in any web browser.

[PsiComa]

Yes, this is exactly the problem. The file isn't changed, but when run through the dropbox browser window (when you share link with dl=0), it gets metallic and distorted.

Is this problem known to the developers?

[madtheory]

It isn’t a problem. All cloud storage systems work today way, all media files get compressed in the browser photos, videos and audio. But if you sync the file to your Dropbox folder on your computer, you get the exact original file.

Think of the browser as a convenient way to preview files. Nothing more. If you want the original file, download it or sync it.

The same thing happens with VLC for Android/ iOS, it dies some pretty bad sounding transcoding when you play media off your cloud. Google Drive or Dropbox, sound the same through VLC.

[PsiComa]

Thanks for your reply. But how does services like Soundcloud and Youtube manage to get undistorted sounds through a browser? In fact, I don't hear much distortion when streaming from Google Drive either.

[madtheory]

Actually there can be distortion there as well, depending on what format was used for upload. Transcoding, same problem we're hearing here.

But you can't compare those services, that are designed for media streaming, with Dropbox, which is not a media streaming service. There are a bunch of code optimisations that work well for streaming that would not be optimal with a cloud storage system. Checksums, for a start.

[LiamFitz]

Wait! This is very helpful. I'm listening to a master right now on my iphone through earbuds. It sounds as clear as a bell on all speakers, headphones, etc when I'm listening through to the files via my hard drive, or a cd. When I use the dropbox audio player, I'm getting distortion that sounds like clipping.

What you're saying is what I'm suspecting?  The dropbox audio player compresses the file and isn't necessarily the best at doing that function? They aren't focusing their attention on creating the best streaming service. It's just a file preview.

Am I understanding that correctly? When I'm listening on my phone thru the amp, it's still playing the cloud file on their end through their browser media player.  If I were to download the file onto my phone and play via music, I shouldn't experience the same compression/distortion?

thanks, Liam

[LiamFitz]

I answered my own questions! I downloaded the file to my phone and played it through the phones music player. All the clipping distortion is gone.