I love Spotify. But I've noticed some weird artifacts on a few albums. It sounds like a fluttery warble noise in the midrange. It's most noticeable during big string or choir sections with broad spectral content.
The problem seems limited to certain albums. The worst album I've come across is this Pascal Roge Poulenc album.
Spotify uses Ogg Vorbis encoding. Free streaming accounts get Ogg Vorbis q5, 160kbps. I wonder if this is a normal Ogg Vorbis artifact, or something more complicated. Here are some audio samples. Can you hear it?
I just upgraded to Spotify Premium and switched to 320kbps high quality streaming. I'm sad to say the nasty artifacts are still audible on these songs.
Due to investigative effort by Ulysses at spotifyclassical.com, this is no longer a mystery but indeed just a case of bad compression; it turns out maybe 50 percent of the Spotify library is actually available at 320kbps.
If this is true then I don't like Ogg Vorbis, since their 160kbps rate seems to have far more annoying artifacts than any 160kbps MP3 I've ever heard. Ogg is supposed to be better.I have not been able to reproduce the artifacts with my own Ogg compressor.
I compared the latest Three Doors Down album on Spotify, Rdio, and FLAC original audio. It's pretty clear that sometimes, the labels just supply bad tracks to the streaming services. The Spotify and Rdio tracks were identical. I heard the same artifacts at the same points in the song. The FLAC was very different. This changes some of my earlier conclusions. The artifacts are not Ogg 160kbps artifacts.
To answer my question above, the warbling noise is definitely not part of the original Three Doors Down - When You're Young track. Now the question is, exactly what format are these tracks provided in, and why is there such variance even among a single label's catalog? Are these differences intentional?
Finally, the source of all this consternation: Universal Media Group supplies heavily watermarked audio to all services. More.