Spotify performing normalization/compression even when turned off?

[_russin]

Was doing some A/B testing on a new amp and headphones, and I noticed something very odd:

The exact same track (e.g. - literally the same file) when playing in my Spotify Library sounded slightly different when played in iTunes. We're talking about an MP3 on my hard drive that I have in both libraries.

It sounded a bit muffled, so I started testing iTunes against Spotify and I was 100% reproducing blind tests picking which one I was listening to due to a roll-off in the mids/highs.

I investigated further by running through a visual EQ, and low and behold, there was some degredation around the 7-10k frequency range of the spectrum.

I went into my settings to make sure that volume normalization was turned off - confirming it was. Did a fresh install of Spotify just in case something whacky was going on, but still the same drop-off.

I tested a number of files from my library, as well as comparing the same tracks that I had locally to the Spotify version of the tracks. Obviously the latter doesn't prove much, since the version of the file might be the same, but the former is pretty damning.

Could this be a bug and normalization is not getting turned off somehow? I've always trusted that when I needed Spotify for hi-fi purposes, I'd be in good shape with Extreme/Premium quality, but seems like Spotify isn't even playing files from my own library correctly. 

Any ideas?

[jimmasterchief]

I came across this issue and did a comparison of 3 versions of the same track. As you can see spotify always compresses the music doesn't matter if you turn loudness normalization on or off. That just changes the level.