The Traders' Den  

  The Traders' Den > Where we go to learn ..... > Technobabble > Lossy or Lossless?
 

Notices

Lossy or Lossless? Please use this forum to post spectral and frequency analysis posts about shows you have your doubts about.

Reply
 
Thread Tools
  #31  
Old 2005-06-05, 06:44 PM
Five's Avatar
Five Five is offline
TTD Staff
186.65 GB/588.32 GB/3.15
 
Join Date: Oct 2004
Location: Canada
Re: Devendra Banhart - Live @ KCRW; Lossy Source? (Freq. screencap inside)

AnalFreq crashed on me too, but at the very end of the test. I ran the whole track, then when the error box came up at the end I moved it aside and took a screenshot of the final results. I'm not sure why AnalFreq likes to crash sometimes, its an old prog that is now available as $hareware (now called SpectraScope) I imagine the newer version has this issue fixed. Hopefully you can get AnalFreq working on your comp somehow it's a great tool.

The Audacity FA is something like 21 seconds, that's all it can handle at once. Highlight a section, choose view>plot spectrum and it will take the 1st 21 or so seconds of whatever you selected and analyze it. In the past when I was having trouble getting a FA to display something useful Audacity has come thru for me not quite sure why that is. My knowledge tends to be pragmatic in nature, the math and esoteric stuff is sometimes beyond my depth of knowledge. But I have a pretty good idea of what works for my purposes and trust the ppl with university degrees to step in and explain exactly why lol.
__________________
Checksums Demystified EAC Config MakeTorrent WinAmp Config

Modern social theory casts a highly skeptical eye on any declaration that a group of persons is without conflict, and insists, on the contrary, that conflict is natural to groups, and even more, is essential to them. -Patrick Henry
Reply With Quote Reply with Nested Quotes
  #32  
Old 2005-06-06, 06:44 AM
range_hood's Avatar
range_hood range_hood is offline
lsmf
11.44 GB/10.00 GB/0.87
 
Join Date: Apr 2005
Re: Devendra Banhart - Live @ KCRW; Lossy Source? (Freq. screencap inside)

Quote:
Originally Posted by Five
AnalFreq crashed on me too, but at the very end of the test. I ran the whole track, then when the error box came up at the end I moved it aside and took a screenshot of the final results. I'm not sure why AnalFreq likes to crash sometimes, its an old prog that is now available as $hareware (now called SpectraScope) I imagine the newer version has this issue fixed. Hopefully you can get AnalFreq working on your comp somehow it's a great tool.
AnalFreq crashes every time before it puts out anything.
Why donīt you like the Cool Edit FA?
Reply With Quote Reply with Nested Quotes
  #33  
Old 2005-06-06, 10:38 AM
Five's Avatar
Five Five is offline
TTD Staff
186.65 GB/588.32 GB/3.15
 
Join Date: Oct 2004
Location: Canada
Re: Devendra Banhart - Live @ KCRW; Lossy Source? (Freq. screencap inside)

the CEP FA is okay, its just that I've done FA using everything I can get my hands on and I seem to be able to read audacity and analfreq more easily than CEP. Especially when the dropoff goes down like stairsteps its hard to see that with CEP FA. I like audacity the best for FA, cep for SA at this point.
__________________
Checksums Demystified EAC Config MakeTorrent WinAmp Config

Modern social theory casts a highly skeptical eye on any declaration that a group of persons is without conflict, and insists, on the contrary, that conflict is natural to groups, and even more, is essential to them. -Patrick Henry
Reply With Quote Reply with Nested Quotes
  #34  
Old 2005-06-08, 09:35 PM
ssamadhi97's Avatar
ssamadhi97 ssamadhi97 is offline
meow.
87.81 GB/69.41 GB/0.79
 
Join Date: Nov 2004
Location: Old Europe
Re: Devendra Banhart - Live @ KCRW; Lossy Source? (Freq. screencap inside)

I'd say this one is mp3 / similar lossy webcast source. Probably even rm.

1) listen to the side channel / stereo difference. *warble*.

2) check out the impulse response whenever strings are touched. pre-echo like whoa. typical flaw of low-bitrate transform-based lossy codecs when it comes to transient signals.


And I'd say it's most likely not (or not only) mp2 - reason 2) again, most mp2 encoders have excellent transient handling unless you really starve them for bitrate (which would mean introducing a world of other audible flaws, too)
Reply With Quote Reply with Nested Quotes
  #35  
Old 2005-06-09, 02:57 AM
rabble
0.00 KB/0.00 KB/---
 
Re: Devendra Banhart - Live @ KCRW; Lossy Source? (Freq. screencap inside)

Well, craptacular. Looks like I won't be seeding this one then, I'll just have to keep my eyes peeled for a lossless source.

Thanks again for the help, ya'll!
Reply With Quote Reply with Nested Quotes
  #36  
Old 2005-06-09, 07:48 PM
4candles 4candles is offline
6.36 GB/18.25 GB/2.87
 
Join Date: Nov 2004
Re: Devendra Banhart - Live @ KCRW; Lossy Source? (Freq. screencap inside)

Quote:
Originally Posted by Five
Okay I had a look and a listen. There's almost no activity above 16kHz, just a slight bit of noise. Using better FA shows quite a steep drop at 16kHz just like the SA is showing. The frequency response is sawed off right at 16kHz in a way that doesn't look like nr. I now believe this is a webcast/mp2 broadcast that's been thru a very clean analog stage which has added that tiny bit of noise in the highs. In terms of sound there's some slurring audible in the sibilants which is typical of FM and lossy but the sound is maybe a bit too nice for a typical RM webcast. I would make note of this information in the .txt file and trade it as a "best available source" most likely SBD>?>?mp2>?FM>unknown (most likely analog) transfer>FLAC
Why doesn't anyone research these things? KCRW broadcasts a 128kbit/s live MP3 stream (which isn't archived). IMO, this is the most likely source.

If the "taper" made the common mistake of recording the webcast by simply pressing record in a sound editor (instead of capturing the original MP3 data), then he/she was recording the analogue sound inside the soundcard - which would add the "tiny bit of noise in the highs" you describe.

But what I'm interested to know is the effect of analogue stages on MP3 compression. i.e. if you take an MP3 file and pass it through an analogue generation what does the spectral analysis look like?
Reply With Quote Reply with Nested Quotes
  #37  
Old 2005-06-09, 09:25 PM
Five's Avatar
Five Five is offline
TTD Staff
186.65 GB/588.32 GB/3.15
 
Join Date: Oct 2004
Location: Canada
Re: Devendra Banhart - Live @ KCRW; Lossy Source? (Freq. screencap inside)

d'oh! good job, a bit of research goes a long way.

Quote:
Originally Posted by 4candles
But what I'm interested to know is the effect of analogue stages on MP3 compression. i.e. if you take an MP3 file and pass it through an analogue generation what does the spectral analysis look like?
probably exactly as seen here. not a lot of difference in the SA, just a light haze in the highs, FA would show a lift in the highs which is only caused by noise. It also depends on the quality of the sound card how much noise gets added. Also, the blockiness would appear somewhat "smeared" in SA. Some day I'll take the time to pass an mp3 out to analog and back again thru a couple different sound cards and post the results.
__________________
Checksums Demystified EAC Config MakeTorrent WinAmp Config

Modern social theory casts a highly skeptical eye on any declaration that a group of persons is without conflict, and insists, on the contrary, that conflict is natural to groups, and even more, is essential to them. -Patrick Henry
Reply With Quote Reply with Nested Quotes
  #38  
Old 2005-06-21, 07:55 AM
range_hood's Avatar
range_hood range_hood is offline
lsmf
11.44 GB/10.00 GB/0.87
 
Join Date: Apr 2005
Re: Devendra Banhart - Live @ KCRW; Lossy Source? (Freq. screencap inside)

Got some spare time. Did some recordings off KCRWs webcasts. The shots on the right side are actually black/white in cool edit (under options > setting > colors if someone cares).
So it seems the source in question contains real video format.

Reply With Quote Reply with Nested Quotes
Reply

The Traders' Den > Where we go to learn ..... > Technobabble > Lossy or Lossless?

Similar Threads
Thread Forum Replies Last Post
Spotting Lossy Sources--links inside - Five Lossy or Lossless? 62 2014-03-05 03:39 PM
A lossy source? - corsair Lossy or Lossless? 1 2007-01-01 05:07 AM
lossy source? - jadg2 Lossy or Lossless? 6 2006-11-27 07:52 PM
Lossy Source? - moebootz Lossy or Lossless? 7 2006-10-02 11:33 AM
Is this mp3 or lossy? It's SBD source - fatoldpig Lossy or Lossless? 3 2006-07-09 11:36 PM


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forums


All times are GMT -5. The time now is 07:24 PM.


Powered by: vBulletin, Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Copyright ©2004 - , TheTradersDen.org - All Rights Reserved - Hosted at QuickPacket
no new posts