Can a 320 kbps mp3 file be "bad?"

[chewy4]

Quote:

 
That's a valid point. I may choose to keep most of the mp3 files I have now, as long as the quality is good.  
 
I feel a bit uneasy about the possibility that some songs could have been converted to 320kbps from a lower bitrate. I think you or some other user mentioned checking spectrum or something using Spek/Spectro? I've found the webpage but I'm not sure if I could make sense of the information given to me by the software

You could always post the image here and people will give you the diagnosis.
 
As for scratched CD's that you mentioned earlier, there is a lot of redundant data on CD's so they really have to be scratched to hell before they start messing up. And even so they'll just skip and whatnot. Nothing to do with audio quality as a whole, it only effects the moments that skip.

 

[julian67]

....they really have to be scratched to hell before they start messing up. And even so they'll just skip and whatnot. Nothing to do with audio quality as a whole, it only effects the moments that skip.

And hardware CD players have good error correction and usually cope well even with badly scratched discs. I've found a few discs that skip in a CD player but which could be ripped accurately, given some patience and the willingness to try different drives, rippers and rip strategies (burst vs secure, with/without c2 etc.).

 

[Empire1]

Hey, just curious, can anyone help me out and listen to this track? 
 
http://media.interactiveone.com/indyhiphop.com/files/2011/10/wop.mp3
 
I downloaded it and iTunes says lists the encoder used as "unknown." I'm curious to see if someone can hear if this file is bad or not. 

 

[julian67]

In a hex editor you can see that the file header contains references to WMA9 so I assume the mp3 was created with that app.

I made a spectrogram. It suggests a blizzard of clipping which is confirmed by Audacity clipping analyser. I didn't listen to it as you can do that for yourself.

 

[bigshot]

Probably hot mastered.

 

[proton007]

The fact that the encoder allows one to encode at a higher bit rate from any source file can be an issue.
This means that you can encode a 64kbps file to 320kbps. It'll sound like 64kbps, but in all other respects, its a 320kbps file.
 
Hence, its hard to accurately determine the source.

 

[bigshot]

I've never understood why someone would bother to do that.

 

[proton007]

Quote:

I've never understood why someone would bother to do that.

 
Well, it happens in internet downloads. The original source probably ripped in 192kbps or 160kbps VBR, but some just convert it to pass it off as 'high quality' 320kbps.

 

[Empire1]

Quote:

In a hex editor you can see that the file header contains references to WMA9 so I assume the mp3 was created with that app.

I made a spectrogram. It suggests a blizzard of clipping which is confirmed by Audacity clipping analyser. I didn't listen to it as you can do that for yourself.

Sorry for my amateurishness, but what do you mean by 'clipping'? 
 
I asked for help if someone could listen to it because all I have at the moment are Bose headphones 

 You can't hear the difference in anything with these 

 

[bigshot]

When the volume goes so high it gets into distortion, that's called clipping. It shows up in the waveform red. Believe it or not, they engineer music that way deliberately so it sounds "loud".

 

[Empire1]

Quote:

When the volume goes so high it gets into distortion, that's called clipping. It shows up in the waveform red. Believe it or not, they engineer music that way deliberately so it sounds "loud".

Hm, so what does this mean this track has been converted from a low quality file?

 

[ab initio]

Hm, so what does this mean this track has been converted from a low quality file?

No, not necessarily. Clipping is related to the loudness of the audio. This shows clipping because either 1) the artist or recording engineer made the track with excessive volume and even the highest quality encoding will exhibit the same clipping
Or 2) somebody took the original recording and boosted the volume before encoding it to this format, which caused the loudest parts to clip

Cheers

 

[julian67]

Sorry for my amateurishness, but what do you mean by 'clipping'? 

http://wiki.hydrogenaudio.org/index.php?title=Clipping

 

[bigshot]

No, not necessarily. Clipping is related to the loudness of the audio. This shows clipping because either 1) the artist or recording engineer made the track with excessive volume and even the highest quality encoding will exhibit the same clipping
Or 2) somebody took the original recording and boosted the volume before encoding it to this format, which caused the loudest parts to clip

MUCH more likely to be number 1

 

[julian67]

.....Or 2) somebody took the original recording and boosted the volume before encoding it to this format, which caused the loudest parts to clip

In fact there is no need for the person to boost the volume to get this same result. Lossy encoding alone can cause clipping with some samples, see previous link to hydrogen audio wiki:

Lossy audio encoding and decoding can cause the highest/lowest sample values to go over the allowed limit (in practice having the sequential max/min values), which may lead to clipping seen by analysis tools, or even audible clipping. But whether the clipping is truly audible or not is a totally different thing. There are different methods to avoid clipping in lossy audio. Look at the specific audio format answers how to best avoid clipping in each case.

Now consider that happening twice or more.

I have even bought flac files from a quite well known legitimate music store and found that some were derived from lossy files (I corresponded with the store who informed me the files had been supplied in this form by the performing artists and to their credit they went to some effort to replace the files with ones losslessly encoded from CD). If you get music by any means where you are unable to verify the origin then all bets are off. It's not exactly unknown to come across music files that have been through lossy encoders more than once.