Microsoft ADPCM

I know this format is lossy, 4:1 compression ratio, But I need to know the technical details.

I accidently set my Archos Gmini400 to record in this format yesterday, the concert sounds ok, and freq. analysis shows tons of activity well above 22khz but I know it's gotta be lossy.

Cool Edit Pro had this to say

Microsoft ADPCM (.WAV)
The Microsoft ADPCM format consists of 4-bit per channel compressed data, which provides 4:1 compression). Files saved in this format will automatically be expanded to 16-bits when loaded, regardless of their original resolution. For this reason, it’s best to save to this format from a 16-bit waveform rather than 8-bit, as the quality will be much greater.

Someone more techincal than me care to explain what was lost due to my error?
Note I have no plans to trade this concert due to the error.

[Five]

if you can post a yousendit.com link I can take a look at it for you and show some screenshots here

Originally Posted by Injektilo*

I know this format is lossy, 4:1 compression ratio, But I need to know the technical details.

I accidently set my Archos Gmini400 to record in this format yesterday, the concert sounds ok, and freq. analysis shows tons of activity well above 22khz but I know it's gotta be lossy.

Cool Edit Pro had this to say

Someone more techincal than me care to explain what was lost due to my error?
Note I have no plans to trade this concert due to the error.

I MAY BE WRONG BUT THAT FORMAT IS SIMILIAR TO THE ROLAND ATHRAC
HARD DISC RECORDING FORMAT

AND IT HAS BEEB USED BY SOME INDIE BANDS IN MAKING THEIR ENTIRE PROJECTS THEN MASTERED TO CD

ok YSI link for a 1min wav file (this was converted into a PCM wav)
I would post screen shots of the Spectrum Analysis but I have no idea what I'm looking at.
http://s50.yousendit.com/d.aspx?id=2...70AEM3E1CREWLG

I can do AnalFreq though.