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View Full Version : My CDR Collection Needs Your Help. ARE THESE LOSSY?


Powerfan
2010-07-03, 05:41 PM
Hey everyone, thanks for helping me with my previous questions about how to test for lossy/lossless. I spent a long time and went through roughly 300+ CDR shows and tested them all for lossy/lossless using audacity.

For the majority of my collection, it was clear cut what were lossy and what were lossless. The others I really have no idea on and need help. I need everyone's help identifying if certain shows in my collection are lossless or not.

Here is the first one I am having trouble with. I can't tell if this is MP3 or lossless. The source claims to be from KGB-FM. Included are a frequency analysis and spectrum. I suspect this is MP3, but the only reason I have doubt is because I read here (http://members.shaw.ca/cdrchow/mp3.html) that certain FM shows have a lower frequency in general.

Any help would be very much appreciated!

tonebloke
2010-07-04, 02:37 AM
G'day P. If I had to guess I'd say lossy; even with being from a radio source, but:
I use CEP and use greyscale colours on the display - it's easier to read (thanks to DrG). Can you re-up the spectrals in greyscale.
You should find the settings in Options>Settings>Spectral.

Thulani
2010-07-04, 06:56 AM
It looks lossless to me.

Powerfan
2010-07-05, 07:45 PM
G'day P. If I had to guess I'd say lossy; even with being from a radio source, but:
I use CEP and use greyscale colours on the display - it's easier to read (thanks to DrG). Can you re-up the spectrals in greyscale.
You should find the settings in Options>Settings>Spectral.

Is this better? You suspect it's lossy and kill_them_all1000 says it looks lossless, so I don't know what to think. I can't tell for myself.

tonebloke
2010-07-06, 02:00 AM
Thanks for the image.

I'm no expert. I'm learning more everyday.
Looking at the peaks @<hidden> 16000 leads me to say lossy, BUT, those peaks don't look consistant through the whole song. An eMPty3 sourced song would basically look like a straight line (see image, ignore the spikes).
I think someone more knowledgable needs to answer this one.

Thulani
2010-07-06, 06:16 AM
I don't see artifacts let by the mp3 codec. Still think it's lossless.

slewofboots
2010-07-13, 11:14 AM
Is this better? You suspect it's lossy and kill_them_all1000 says it looks lossless, so I don't know what to think. I can't tell for myself.

You need a 2-sec chunk to see "microgaps" indicating .mp3 in the ancestry. Looking at the whole song like this doesn't tell you enough...

Powerfan
2010-07-13, 09:16 PM
You need a 2-sec chunk to see "microgaps" indicating .mp3 in the ancestry. Looking at the whole song like this doesn't tell you enough...

Here are some screen shots of a two second zoom-in on the audio in question. I'm still stumped. Any help is appreciated :)