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Five
2020-02-26, 05:43 PM
I recently discovered this software, it is so great for spectral analysis try it out. it generates the screencaps and everything.

how to understand read some here
http://www.thetradersden.org/forums/forumdisplay.php?f=47

I would call it essential ttd recommended software at this point
http://spek.cc/
Spek – Acoustic Spectrum Analyser

Spek (IPA: /spɛk/, ‘bacon’ in Dutch) helps to analyse your audio files by showing their spectrogram. Spek is free software available for Unix, Windows and Mac OS X.
Features

Supports all popular lossy and lossless audio file formats thanks to the FFmpeg libraries.
Ultra-fast signal processing, uses multiple threads to further speed up the analysis.
Shows the codec name and the audio signal parameters.
Allows to save the spectrogram as an image file.
Drag-and-drop support; associates with common audio file formats.
Auto-fitting time, frequency and spectral density rulers.
Adjustable spectral density range.
Translated into 19 languages.

Screenshots
Spek running under Ubuntu Linux Spek running under Windows 7 Spek running under Mac OS X

Download
Unix spek-0.8.2.tar.xz (168 KiB)
instructions
manual

Windows spek-0.8.2.msi (8.47 MiB)
spek-0.8.2.zip (8.35 MiB)
instructions

Mac OS X spek-0.8.3.dmg (6.03 MiB)
instructions
News news feed

2014-08-31: Faster Fast Fourier Transform
2012-09-23: Spek 0.8.0 Released
2011-08-17: Spek and Lion
2011-04-24: Spek 0.7 Released
2011-03-16: Spek status update


Contribute

Spek is free and open source software licensed under GPLv3. The project is written in C++, the code is available on GitHub.

Report bugs and request new features on the issue tracker.

Five
2020-02-26, 05:46 PM
you can easily generate images like these for posting to boards, showing to people when you have a questionable source...

flac

Five
2020-02-26, 05:47 PM
320kbps mp3

Five
2020-02-26, 05:48 PM
mac osx leopard Russian translation version, too!

Five
2020-02-26, 07:02 PM
it is the software we dreamed of when we were writing the FAQ back in the day. its like they designed this made to order for ttd traders' exact mp3 spotting needs. no more screen captures and saving from ms paint/whatever it spits an image out for you. cross platform free software. stable as a rock since 2014.

pawel
2020-02-28, 03:05 PM
To have more detailed view of higher frequencies hold ctrl and click a few times up arrow.

BTW: Five, it's time for TD to enable mp2 and ac3 DAB. They are often cleaner than a terrestrial FM. No mention that most of FM is compressed at source.

davebowman
2020-02-29, 10:52 AM
'Point and Go' software, works great on LINUX.

Been using it for a while now. :)

Five
2020-03-01, 11:30 AM
To have more detailed view of higher frequencies hold ctrl and click a few times up arrow.

BTW: Five, it's time for TD to enable mp2 and ac3 DAB. They are often cleaner than a terrestrial FM. No mention that most of FM is compressed at source.
yes we've been talking about this for 16yrs now :)

there is some president for 'best available source' lossy broadcast as FLAC but not mp2 or ac3.

I imagine 'lossy at the den' forum its a hard sell for staff and members alike.

can we ever solve this? since stg? :lol:

pawel
2020-03-01, 12:03 PM
Ban all videos which have ac3 / mp2 :lol4:

Five
2020-03-01, 11:08 PM
how do we write the faq entry?

how to cut mp2 & ac3 without recompressing?

detecting double-compression?

my relationship with lossy is seek-and-destroy from the abtd section. video is another ball of yarn..

of course you are right pure mp2/ac3 original clean capture is logical but its a great unknown. are any other sites allowing these? on dime?

pawel
2020-03-02, 02:48 PM
how do we write the faq entry?
how to cut mp2 & ac3 without recompressing?
mp3DirectCut (https://mpesch3.de/) also for AAC

detecting double-compression?
By lineage, and spectral analysis only, however the second is not very precise.

of course you are right pure mp2/ac3 original clean capture is logical but its a great unknown. are any other sites allowing these? on dime?
Yep, Dime allows direct captures of DAB but also conversion to wav > flac which is a nonsense imo, particularly in case of downsampling from 48 to 44.1 kHz.

Five
2020-03-02, 03:15 PM
Yep, Dime allows direct captures of DAB but also conversion to wav > flac which is a nonsense imo, particularly in case of downsampling from 48 to 44.1 kHz.
:mad:

this is great you brought this up... as I understand it early (and later) etree.org approved shn dat rips were converted wholesale from 48kHz to 44.1kHz. Now that we don't use cds those gd/phish people need to get to work capturing perfectly at 48kHz before they all die and the dats are lost. etree 2020, this is where we are at.

back on topic, (astonishingly) sounds fine so far. what goes wrong with this? what 'bad seeds' abusing this loophole will show up (examples from dime if you've seen). I'm imagining ppl capturing mp3 badly and changing to mp2 extension like an idiot. can we differentiate mp2/mp3? ac3 is very difficult to spot (pls help) and theoretically could cause similar problems.

pawel
2020-03-08, 08:48 AM
It's quite difficult to recognize mp3 / aac / ogg sourced audio, particularly compression which is done nowadays, when better software is widely and freely available. Mp3 may compress without much visible cuts up to 20 kHz, and looks like a bit processed SBD - i.e. denoised.

Majority of software based mp2 codecs cut at 16 kHz, and you see "shreds" at higher frequencies. However, hardware used by radio allow to go up to 20 kHz, and it may look (and sound!) much better than (older) FM or SBD. I expect than most European FM goes through a hardware compressor now as they also broadcast as DAB and/or DVB-S.

I think that what you do at TTD, demanding detailed lineage, helps a lot to eliminate suspicious sources which have double lossy way, and then additionally checked by the members. BTW: they are a few shows already on the tracker which escaped your attention :lol4: Normal, hard to check everything...