Help expand my knowledge about lossless, WAV and Mp3

[forrestcupp]

Actually, I did about 20, random, double-blind tests and my ability to recognize the MP3 was 100% accurate and furthermore I was able to tell within just the first few notes. So my experience is that it is obvious.

What kbps were the mp3s? If you're talking about 128 kbps, then yes, but after a certain level, it becomes less obvious.

[blueturtl]

Specifically, the process of converting a .wav file into an .mp3 file clips the top and bottom frequencies. These frequencies are above and below the range that a typical person can hear. This clipping is responsible for why the bass line in an .mp3 doesn't produce the same amount of vibrations in your furniture that an uncompressed file can produce (assuming you speakers that can handle it). This is why the procedure is "lossy"; you've lost some of the dynamic range of frequencies. Since there is less to compress after the top and bottom ranges have been stripped out, an .mp3 can be much smaller than a .flac file, which compresses the entire original range.

I thought the MP3 algorithm worked by removing sounds that would be audible to the human ear, but masked by other sounds. I also thought dynamic range referred to the differences of quiet and loud parts in a recording (ie. a recording with low dynamic range wouldn't have very big differences between the quiet and loud parts of the recording when it comes to the volume level).

How far out in the woods am I?

[David Andersson]

Originally Posted by thatguruguy View Post
Specifically, the process of converting a .wav file into an .mp3 file clips the top and bottom frequencies. These frequencies are above and below the range that a typical person can hear...

I thought the MP3 algorithm worked by removing sounds that would be audible to the human ear, but masked by other sounds. I also thought dynamic range referred to the differences of quiet and loud parts in a recording ...

How far out in the woods am I?

You are basically right and the post you are quoting is an over-simplification. (Cutting hi and low frequencies only saves a few percent.)

[David Andersson]

now if we have an MP3 that's been converted from WAV and convert it back to WAV does the audio regain the quality of it's original state or just make the file bigger with benificial reason for changing back to WAV?

I like the photo copier analogy. You have a sharp photo. Copy it in a bad copier and you get a blurry photo. You can not take the blurred photo, copy it in a good copier and expect a sharp photo to come out.

Same with: color photo -> black/white copier -> black/white photo -> color copier -> still black/white photo.

[KUU]

Thanks for the feedback all,