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View Full Version : Help proving if it's lossy or not...


Buda
2009-02-08, 08:02 PM
As I can't produce or read FAs or SAs, though I'm learning I tought someone with proper eyes can tell me if these tracks are lossless in order to up the show in its most complete.

xx Whole Lotta Rosie ORIGINAL (Live Samurai Vol 2).flac
http://www.sendspace.com/file/j13jv8

05 - Whole Lotta Rosie.flac - 1987 June 28 from bootleg Civil War
http://www.sendspace.com/file/w492h4

Thanks very much for the assistance!

Buda
2009-02-10, 10:19 AM
I hope I managed to capture what's needed. Here are the FAs of the upper tracks and a third source too.

Thanks in advance for all the help!

U2Lynne
2009-02-10, 10:40 AM
I'm not an expert, but those do look fine to me.

Buda
2009-02-10, 12:38 PM
Thanks Lynne for sharing your opinion!

Buda
2009-02-16, 11:21 AM
I got into reading some FAs but with this I can't decide if it's lossy or not... I see there's no decent fall around 14 despite the spike (fm?) only much later... :rolleyes:

This would be a much lower generation rec than available commonly (Guns N' Roses 1987 June 22 London, Marquee). Thanks for all the help

paddington
2009-02-16, 12:06 PM
The 'fall off' shown in a frequency analysis is somewhat irrelevant, as it only shows whether or not the audio has been through a lowpass filter. While undesirable, it has no meaningful use when determining if audio has been through lossy data compression. The only reliable way to be sure is to use a spectrum analyzer to observe a 2-3 second span of the audio and examine for 'blocks' or the 'Lego effect' with your eyes. These 'blocks' are the result of audio chunks being deleted during the lossy data compression. With your ears, you can also listen for a 'glassy' or 'watery' sound in the high freq range... overly-shimmery, watery cymbals, etc.

in the case of your two AC/DC audio samples, all is well.. some very nice, open sounding audio with no evidence of lossy data compression being used.

:thumbsup

Buda
2009-02-16, 02:19 PM
Thaks jameskg for your response. I thought FAs are a bit more trustworthy but from now on SAs are gonna be used definetly. Here's a SA then, another tracks from the very same recording, w me thinking that it seems okay, can't see that lego effect you mentioned...