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Porcupine Tree 5.1 remasters - Deadwing / In Absentia - getting nearer?

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rugene

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There's a bunch of high tech geek here and I am not of them. Just to prove to you, It took me 2 years to discover that I can adjust the decibel level of my speaker with my home theater amp.:confused: It helps me enjoy the Rush Signals 5.1 remix a little more.
 

Plan9

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I guess it's possible that the only two fixes truly needed, then, are to 1) invert the center and 2) raise the LFE.

If a 10ms delay is the result of a filtering tool, then it's not necessarily a "problem" or "mistake".

Now, shifting it back 10ms certainly doesn't harm the sound, to my ears. It's maybe just unnecessary.
That was my conclusion and what I passed on to Steven Wilson.
 

edisonbaggins

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So, any guesses as to how a channel gets inverted?
I know I can do this manually, intentionally, at various points after mix down. I never would though, and I suppose no engineer would either.
Is there some tool or process that might do this? Maybe if some option is overlooked?
 

Frogmort

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I guess it's possible that the only two fixes truly needed, then, are to 1) invert the center and 2) raise the LFE.

If a 10ms delay is the result of a filtering tool, then it's not necessarily a "problem" or "mistake".

Now, shifting it back 10ms certainly doesn't harm the sound, to my ears. It's maybe just unnecessary.
For just simple auditory fidelity, every work channel should be properly time and phase aligned together, from a work-chain production point of view. If a certain effect is meant to be 'early' or 'late', (King Crimson's 'One More Red Nightmare' handclaps are slow as shit, deliberatley/ Bonham and Jones leaned way back on the beat, etc), that's completely different than channel coherence.

I'm pretty much positive that any latency in the LFE .1 channel was accidentally introduced through computer software/hardware glitches. Choosing to adjust LFE time domain delays should be done on the user's end, specific to correcting personal room/setup issues, not in the original source.

P.S.: Yeah, 10ms delay on the LFE channel is probably almost imperceptible, but it's still not properly aligned. From a purely objective point of view, I would just prefer for it to be correct, and in line with everything else. I just can't imagine anyone saying 'It sound's great, but let's just deliberately delay the LFE channel by a few milliseconds'.
 
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edisonbaggins

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For just simple auditory fidelity, every work channel should be properly time and phase aligned together, from a work-chain production point of view. If a certain effect is meant to be 'early' or 'late', (King Crimson's 'One More Red Nightmare' handclaps are slow as shit, deliberatley/ Bonham and Jones leaned way back on the beat, etc), that's completely different than channel coherence.

I'm pretty much positive that any latency in the LFE .1 channel was accidentally introduced through computer software/hardware glitches. Choosing to adjust LFE time domain delays should be done on the user's end, specific to correcting personal room/setup issues, not in the original source.

P.S.: Yeah, 10ms delay on the LFE channel is probably almost imperceptible, but it's still not properly aligned. From a purely objective point of view, I would just prefer for it to be correct, and in line with everything else. I just can't imagine anyone saying 'It sound's great, but let's just deliberately delay the LFE channel by a few milliseconds'.
Your point of view is just as valid as anybody's, IMO. As I say in the recent video, I view questions of this sort in terms of degrees of confidence. I have the highest confidence (near total) that the center was unintentioally flipped. Lower confidence (high) that the LFE was needlessly lowered and the least confidence (not much, but some) that the LFE sync was a mistake.
We never tried a fix that flips the center and raises the LFE unshifted.
Just my $0.02.
 

bluelightning

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Your point of view is just as valid as anybody's, IMO. As I say in the recent video, I view questions of this sort in terms of degrees of confidence. I have the highest confidence (near total) that the center was unintentioally flipped. Lower confidence (high) that the LFE was needlessly lowered and the least confidence (not much, but some) that the LFE sync was a mistake.
We never tried a fix that flips the center and raises the LFE unshifted.
Just my $0.02.
I think people are over analyzing the crap out of this one. There are many ways any of these issues could have occurred . As for LFE gain levels, if it sounds (and feels , very important I must add :) ) good, then just enjoy the bloody thing. Who gives a crap whether it was exactly 7.6dB or not. If it is too bassy, just turn down the bass control. Is it really that hard ?
 

lauti

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Hi guys,
just get hold of the 1st Blu-Ray edition on e-Bay for a few bucks. Any recommendation which fixes to apply? Just inverting the Center channel or also some tweaks to the LFE? Can somone ultimately say in which aspects the corrcted Blu-Ray differs from the original one? As far as I see only the Center has been inverted but no changes to LFE - Can anybody confirm? Thanks!
 

knifeman

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So, any guesses as to how a channel gets inverted?
I know I can do this manually, intentionally, at various points after mix down. I never would though, and I suppose no engineer would either.
Is there some tool or process that might do this? Maybe if some option is overlooked?
At the end of the day, this is a result of poor quality control. It doesn't matter how things get messed up; what matters is that these mistakes are identified and corrected before the disc goes into production. It kills me when members of this forum get a new release and immediately find problems. This is what Kscope should have done, and it defies explanation why they can't and yet hobbyists here can.
 

edisonbaggins

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Hi guys,
just get hold of the 1st Blu-Ray edition on e-Bay for a few bucks. Any recommendation which fixes to apply? Just inverting the Center channel or also some tweaks to the LFE? Can somone ultimately say in which aspects the corrcted Blu-Ray differs from the original one? As far as I see only the Center has been inverted but no changes to LFE - Can anybody confirm? Thanks!
All the information you need is in this thread and the recent review video.
But to recap:
Assuming you rip the BD, you'll want to invert the center channel and and boost the LFE by 7.6 db, for every song.
Optionally, you may want to shift the LFE back 10ms for every song (delete 10ms from the front of it).
 

Delicious2

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Here's Audacity's spectral analysis of several channels of the first loud section of Trains. I guess I shouldn't have been surprised that there's no ULF bass in the LFE (this is music after all not movie sound effects) but I was definitely surprised that the same low bass was present and louder in all other channels including the center! (note the -41db peaks in the LFE)
Trains from Original DVDa not much in LFE.JPG
 

Delicious2

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Even the center has more low bass than the LFE with around -32db peaks. I guess this mix doesn't depend on the end user to have a capable sub (or any sub at all) for the low bass to come through.
Trains from Original DVDa more bass in center than LFE.JPG
 

V96GLF

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So, in summary... if I already own the DVD-A version, is there any reason to buy the (corrected) new release?
 

JediJoker

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So, in summary... if I already own the DVD-A version, is there any reason to buy the (corrected) new release?
If you can rip, correct, and then play the lossless surround from the DVD-A—and you don't care about the additional content on the Blu-ray or box set (bonus tracks, more dynamic and bassier stereo remaster, documentary, demos on CD)—then you can safely sit this one out. If, however, you cannot rip, correct, and then play the DVD-A, then the corrected Blu-ray may be of interest because it fixes the biggest problem with the surround audio (inverted center channel polarity).
 

V96GLF

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If you can rip, correct, and then play the lossless surround from the DVD-A—and you don't care about the additional content on the Blu-ray or box set (bonus tracks, more dynamic and bassier stereo remaster, documentary, demos on CD)—then you can safely sit this one out. If, however, you cannot rip, correct, and then play the DVD-A, then the corrected Blu-ray may be of interest because it fixes the biggest problem with the surround audio (inverted center channel polarity).
Excellent answer - thanks.

I prefer to play from the disc, so time to get out the credit card.
 
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