[ab initio]

Quote:

 
Sounds like a plan. Thank you guys for all the wonderful help, wish me luck!  

Good luck!

 

Cheers

 

[ferday]

Well the top one is like 6dB louder. Most likely a different master. The first one's meta data says it's from a best of album, maybe the second is from the original.

They also both have a soft frequency cutoff at around 16kHz, which is not a property of 320kbps [LAME] mp3. AFAIK those soft frequency barrier are a property of AAC. They were upconverted from something, probably either 192kbps or 128kbps AAC.

So they're both transcoded, but the difference you hear might just be a result of a different mastering. Get your music from a legal source and you wont run into this problem. Also by the way you're going to end up with malware going to sites like those.

A 16khz cutoff is a very common mp3 encoding artifact, usually 128kbps but not always. Newer lame will very often filter if not entirely cut off everything above 16khz. Because there is supposed to be little usable info up there it is a common place to steal space from

Hydrogen audio has a dozen good threads on the subject and this page has some good diagrams

http://www.walterdevos.be/how-to-check-quality-of-mp3-file

I would venture to say that AAC to mp3 transcodes are actually quite rare, since someone only gets AAC on purpose there wouldn't be much reason to transcode to mp3. All legal (or otherwise) download sites have mp3 already. But one never knows

 

[chewy4]

Quote:

A 16khz cutoff is a very common mp3 encoding artifact, usually 128kbps but not always. Newer lame will very often filter if not entirely cut off everything above 16khz. Because there is supposed to be little usable info up there it is a common place to steal space from

Hydrogen audio has a dozen good threads on the subject and this page has some good diagrams

http://www.walterdevos.be/how-to-check-quality-of-mp3-file

I would venture to say that AAC to mp3 transcodes are actually quite rare, since someone only gets AAC on purpose there wouldn't be much reason to transcode to mp3. All legal (or otherwise) download sites have mp3 already. But one never knows

From my experience the cutoff in LAME mp3 is pretty solid, whereas in AAC it just removes a lot more data above the line but doesn't completely remove it(which is what I meant by "soft" frequency barrier). I have no experience in Frauenhofer MP3's, and also a 128kbps LAME file might look like that with some different parameters than normal. The file the TC posted does look similar to the fake MP3 file in your link(5th picture down).
 
iTunes is one of the most popular digital download storefronts and it has aac only, so it would make sense for me for someone to buy it from iTunes and then convert it to mp3, since mp3 is a bit more compatible with everything. And I believed iTunes used to sell 128kbps aac files.
 
Either way the file is junk, who knows where it's been.

 

[julian67]

Also quite common are mp3 transcoded from BBC's iPlayer listen again service which uses aac. This won't be full albums but plenty of tracks, studio sessions, live performances of concerts, festivals, spoken word etc.

 

[bigshot]

The problem with low bitrate lossy files isn't a rolloff at 16kHz. That barely affects anything. The problem is artifacting.