I'd also expect the MP3 version to have a gate-like effect on noise in extreme high frequencies, though I can't hear that on my loudspeakers and I don't have headphones available at the moment. This is clearly visible in the track spectrogram view.
If I want to gate high frequencies (or any other audible change), I'd rather do it intentionally with an effect rather than have it done automatically as a consequence of data compression. Ideally I would want the exported sound to be as similar as possible to my original, and WAV does that better (more accurately) than any lossy compressed formats.Black Dog Bluez wrote:if cancelling bad sounds for good?
All "lossy compression" formats (MP3, Ogg, MP2. AAC ...) discard "unimportant" audio data so as to reduce file size. The lower the bit-rate (smaller files), the more is thrown away. High bit-rates discard less audio data. There are subtle differences between different formats as to how they decide which audio is "important" and which is not. At very low bit-rates, the losses are obvious and, for music, they all sound "bad". At very low bit-rates, the differences between compression formats are clearly audible, for example SPEEX sounds much less bad at extremely low bit-rates than Ogg or MP3, especially for speech, because SPEEX is optimised for low bit-rate speech, whereas OGG and LAME MP3 are optimised for medium to high bit-rate music. (The Speex codec has been obsoleted by Opus)
MP3 licensing has been a nightmare in terms of licensing and IP rights for decades, and in my opinion, one of the best (worst) examples of how patent and intellectual property (IP) law can be abused by big business, hence my personal recommendation to avoid it.