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  • lvqcl
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De-emphasis components
Reply #50
No, it is implemented as a biquad filter, it doesn't use any impulses.

  • SEMteXXL
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De-emphasis components
Reply #51
I see. I tried a little with status bar syntax and here are some possibilities. It was easier than I thought.

Code: [Select]
Pre-Emphasis: $if($meta(pre-emphasis),Yes,No)
or
Code: [Select]
Pre-Emphasis: $if($meta(pre_emphasis),Yes,No)
Depends on your tag name. It doesn't matter which value you are using 1, on or yes. It simply scans for PRE-EMPHASIS or PRE_EMPHASIS tag name presence.

second 
Code: [Select]
Pre-Emphasis: $ifequal($meta(pre-emphasis),1,Yes,No)
or again
Code: [Select]
Pre-Emphasis: $ifequal($meta(pre_emphasis),1,Yes,No)
This one only works with value 1 and NOT with on or yes. I guess there are other possibilities. Hope this helps.
  • Last Edit: 16 December, 2013, 02:19:03 PM by SEMteXXL

  • Hotsoup
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De-emphasis components
Reply #52
I'm experiencing a strange problem - I've uninstalled this component (foo_dsp_deemph) but still seem to notice the effect when applying the %PRE-EMPHASIS% tag or deleting it. There is no active DSP in my chain, just replaygain. I'm currently at work though, looking to test if the same thing happens at my work station where I don't think I've ever installed either plugin, foo_deemph or foo_dsp_deemph. Anyone else able to reproduce this?

EDIT: I also checked for any leftover .dll's in the programs' component folder and APPDATA components folder.
  • Last Edit: 17 September, 2014, 10:36:40 AM by Hotsoup

  • eahm
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De-emphasis components
Reply #53
Is there an effective way to know if a CD/track has pre-emphasis?

Thanks.

  • lvqcl
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De-emphasis components
Reply #54
foo_dsp_effect also has its own deemph postprocessing. But IIRC it uses only PRE_EMPHASIS tag, and not PRE-EMPHASIS.

  • Hotsoup
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De-emphasis components
Reply #55
Is there an effective way to know if a CD/track has pre-emphasis?
I had a few in my collection that were known to have pre-emphasis: an old Dark Side of the Moon, New Order's Low-life (old Nimbus Factory disc), Journey's Frontiers (original US disc and Japan)... But I recently acquired two more discs from Japan on the Canyon label. I wouldn't have known unless dBpoweramp tagged them for me with %PRE-EMPHASIS% = Yes

IIRC, I believe there is a flag on the disc's TOC and/or subchanel information that lets EAC or dBpoweramp know and I'm not sure if any other ripping software besides iTunes accounts for these old discs (although some were or are still being manufactured for whatever reason).
  • Last Edit: 17 September, 2014, 11:17:16 AM by Hotsoup

  • eahm
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De-emphasis components
Reply #56
I had a few in my collection that were known to have pre-emphasis: an old Dark Side of the Moon, New Order's Low-life (old Nimbus Factory disc), Journey's Frontiers (original US disc and Japan)... But I recently acquired two more discs from Japan on the Canyon label. I wouldn't have known unless dBpoweramp tagged them for me with %PRE-EMPHASIS% = Yes

Sorry for keeping OT... mostly for the Pink Floyd albums, what if you only have the files and not the discs anymore, I've never tried but can you scan with dBpa for that feature?

  • Hotsoup
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De-emphasis components
Reply #57
foo_dsp_effect also has its own deemph postprocessing. But IIRC it uses only PRE_EMPHASIS tag, and not PRE-EMPHASIS.
When I noticed this, I was definitely using PRE-EMPHASIS. I know nothing about your code (or coding in general, sorry) but is there some part of post-processing leftover even after removing the component(s)? I'm just spit-balling..

@eahm : To quote one of Greynol's old posts on the subject "apart from an educated guess? no." On the other hand, they'll probably sound especially bright when not de-emphasized. There's a pretty good list going here and on Steve Hoffman's forum of known pre-emph CDs.
  • Last Edit: 17 September, 2014, 12:30:01 PM by Hotsoup

  • eahm
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De-emphasis components
Reply #58
@eahm : To quote one of Greynol's old posts on the subject "apart from an educated guess? no." On the other hand, they'll probably sound especially bright when not de-emphasized. There's a pretty good list going here and on Steve Hoffman's forum of known pre-emph CDs.

Yes, I saw both while ago, I'll ask again in the future, maybe they'll come up with something and I may have one or two albums only anyway. Thanks.

  • Hotsoup
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De-emphasis components
Reply #59
foo_dsp_effect also has its own deemph postprocessing. But IIRC it uses only PRE_EMPHASIS tag, and not PRE-EMPHASIS.

After getting back to the home office I was able to test this. You're right it was foo_dsp_effect and I didn't even make the mental connection to Mudlord's component, especially since it wasn't part of the DSP chain. FWIW, foo_dsp_effect also worked for the tag "PRE-EMPHASIS" and "Yes", not just "PRE_EMPHASIS" and "1". Thanks for the help. I don't know how I got so confused.
  • Last Edit: 17 September, 2014, 11:53:37 PM by Hotsoup

  • madman5150
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De-emphasis components
Reply #60
Hi, I have downloaded the foo_deemph.zip and have a few questions:

- Is there a set of step by step instructions that a novice can follow to install?

- I am using ASIO4all, does foo-deemph just sit in front of that and pass the processed signal to it?

- I gather the filter cuts in automatically ONLY when a pre-emphasised file is detected and that non pre-emphasised files will pass untouched. Is this correct?

- If so, how do I ensure that the relevant files have the correct flag/code.


Sorry for all the questions - I thought the zip would have an idiots guide text file. 

Thanks in advance.

  • lvqcl
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De-emphasis components
Reply #61
1) "How do I install additional components?" from http://www.foobar2000.org/FAQ
2) This component doesn't interact with ASIO4ALL
3) Yes
4) From the 1st post in this thread: "add a tag named PRE_EMPHASIS or PRE-EMPHASIS with a value 1, on or yes"

  • milavla
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De-emphasis components
Reply #62
lvqcl What's the difference between 0.0.3 and 0.1.0 Version?
  • Last Edit: 08 April, 2015, 06:03:35 AM by milavla

  • lvqcl
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De-emphasis components
Reply #63
0.0.3 works only with audio with 44100 Hz samplerate.

0.1.0 can apply deemph filter to audio with 44100, 48000, 88200, 96000, 176400, 192000 Hz samplerate.

  • milavla
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De-emphasis components
Reply #64
lvqcl thanks

De-emphasis components
Reply #65
Quote
Postprocessing (foo_deemph): works only with lossless sources; always active during playback and ReplayGain scan.


Does it mean that it always performs frequency response correction, no matter if audio has pre-emphasis or not? Or it also needs some flags in audio data to start de-emphasis?
  • Last Edit: 29 June, 2015, 02:50:03 AM by Steve Forte Rio

  • Rollin
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De-emphasis components
Reply #66
Does it mean that it always performs frequency response correction, no matter if audio has pre-emphasis or not? Or it also needs some flags in audio data to start de-emphasis?

No.
To de-emphasize a track, add a tag named PRE_EMPHASIS or PRE-EMPHASIS with a value 1, on or yes. Other tracks are unaffected.

  • gism
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De-emphasis components
Reply #67
Use postprocessing if you want to add correct ReplayGain tags to your files.
Use DSP if you have lossy files that you want to de-emphasize.
Otherwise, there's no difference.

I have image files with embedded cuesheet which is replaygained.
Excuse my ignorance, does this mean that I have to re-scan RG after any of these components is installed?
How do they affect RG values?

  • lvqcl
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De-emphasis components
Reply #68
Pre-emphasis increases the loudness of audio, and de-emphasis decreases it. So it makes sense to calculate loudness after applying de-emphasis.

foo_deemph allows this, so you may re-scan albums with pre-emphasis to get better RG values. It's not necessary, but advantageous.

OTOH, foo_dsp_deemph is a usual DSP plugin. It's not possible to take it into account during RG analysis. So, if you use this component then there's no reason to re-scan files (and this means that their loudness will always be slightly off).

  • mjb2006
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De-emphasis components
Reply #69
Quote
this means that their loudness will always be slightly off

Just in case anyone wonders how far off: on Dark Side of the Moon (first CD mastering), it's a difference of 0.03 to 0.08 dB for each track, and 0.05 dB for the whole album. I can't imagine it would be much higher on an album with more high-frequency content. So it's absolutely nothing to worry about. You probably can't detect differences of less than 0.5 dB even with test tones in headphones anyway; see http://www.audiocheck.net/blindtests_index.php.
  • Last Edit: 03 July, 2015, 05:12:07 PM by mjb2006

  • lvqcl
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De-emphasis components
Reply #70
I have an image+cue for Dark Side of the Moon, and here the difference is 1.13 dB (album gain = +1.78 dB w/o de-emphasis, +2.91 with it). But even 1dB difference isn't that big actually.

  • mjb2006
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De-emphasis components
Reply #71
Oh, good catch. I was actually comparing the wrong files!

When I do the R128-based RG scan against the original rip, with de-emphasis i get +2.86 dB, and without I get +1.78. So yes, about a 1 dB difference.

My old tags in the original rip said +2.91 instead of +2.86. This was where I was getting the 0.05 difference from. I'm guessing this is reflecting the use of different de-emphasis algorithms.

  • milavla
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De-emphasis components
Reply #72
lvqcl: foo_deemph works with any lossless sources (ape, wv) or only flac?

  • marc2003
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De-emphasis components
Reply #73
read the first post... 

Quote
Plugins to do de-emphasis of pre-emphasized CDs:
* Postprocessing (foo_deemph): works only with lossless sources; always active during playback and ReplayGain scan.
* DSP plugin (foo_dsp_deemph): works with any source

  • lvqcl
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De-emphasis components
Reply #74
lvqcl: foo_deemph works with any lossless sources (ape, wv) or only flac?

It works with any decoder that supports postprocessing service. Monkey's Audio and WavPack included. Maybe it won't work with the current OptimFROG decoder...