Fixing Aqualung's Quad Mix: The Back Left Channel's Incorrect Polarity; Sometimes Laughably Out of Phase LFE; Swapped Back Channels of "Hymn 43"

[JohnN]

Hey @JohnN: don't mean to derail this thread, but do you have the ear of anyone at Parlophone (or wherever) who could do something about the Blu-Ray disc rot that so many of us have experienced? I even went so far as to contact the QC department at Optimal, who manufactured the discs in question, and they basically said that they'd executed their contract, the warranty period associated with that contract was over long ago, and (sorry, but) there was nothing to be done. I know you were a party to this thread:
https://www.quadraphonicquad.com/forums/threads/jethro-tull-aqualung-bluray-audio-failing.28494/

Tough one. Unfortunately I doubt anyone wants to get involved. The Adapted Aqualung was created because of the production problems. IMO Warner should give free Adapted DVDs to those that complain. TaaB caused a lot of headaches and now Broadsword is dragged out.
Cheers

 

[fizzywiggs41]

Great detective work yet again. Fortunately, we have the Steven Wilson 5.1.

Yes i agree . The SW mix also has the correct guitar solos , in 3 major tunes , Mother Goose , My God , and Locomotive Breath that are absent in the quad mix.

 

[sjcorne]

Unfortunately I doubt anyone wants to get involved.

It’d be great if Chrysalis could be persuaded to release it as a hi-res download, perhaps just to test the waters? Seems like a win-win to me, as no disc manufacturing or authoring expenses are required.

A limited-run SDE Blu-Ray could be another possibility worth exploring.

 

[ssully]

I still wonder if the other underwhelming-sounding Tull quads in these boxed sets, need this sort of attention.

As for disc rot -- rip those discs to files ASAP. We have the technology, why not use it?

 

[paligap]

Do these errors exist on the quad mix on the Adapted Edition as well?

 

[Dynamic Editor]

I still wonder if the other underwhelming-sounding Tull quads in these boxed sets, need this sort of attention.

As for disc rot -- rip those discs to files ASAP. We have the technology, why not use it?

What specific quad releases are those?

 

[Dynamic Editor]

Do these errors exist on the quad mix on the Adapted Edition as well?

Yes, they do.

 

[JohnN]

After Aqualung on Blu-ray, thought was given to releasing Aqualung Adapted in 4.0, but with pulling the tape again (and the cost), the decent Mew transfer was left at 4.1. The approach on the Adapted Edition was to release the original master stereo with minimal adjustment. This is how all other quad was released. Give the fans the sound with minimal correction and in 4.0.

 

[paligap]

This might be a stupid question, but do we even need the LFE in this quad mix?

 

[JohnN]

This might be a stupid question, but do we even need the LFE in this quad mix?

No.
Peter Mew is responsible for the .1 on the Aqualung quad.

 

[ssully]

After Aqualung on Blu-ray, thought was given to releasing Aqualung Adapted in 4.0, but with pulling the tape again (and the cost), the decent Mew transfer was left at 4.1. The approach on the Adapted Edition was to release the original master stereo with minimal adjustment. This is how all other quad was released. Give the fans the sound with minimal correction and in 4.0.

I don't understand this.

 

[ssully]

Do these errors exist on the quad mix on the Adapted Edition as well?

From the top post:

Hello! I was looking at Jethro Tull's quad mix of Aqualung, as it is presented on Blu-Ray in the 40th Anniversary Collector's Edition and on DVD in the 40th Anniversary Adapted Edition

 

[paligap]

To be more precise, are there (enough) low frequency signals in the other 4 channels that would be directed to subwoofers by an AVR with bass management if the LFE channel were somehow removed or muted? In other words, are the low frequency signals in the LFE channel subtracted from or derived from low frequency levels in the other four channels?

 

[ssully]

What specific quad releases are those?

All of them I've heard in addition to Aqualung -- Warchild, Too Old, Minstrel --- sounded kind of poor, actually.

 

[ssully]

This might be a stupid question, but do we even need the LFE in this quad mix?

LFE is unnecessary in virtually all music releases. It was created for movie special effects like explosions and earthquakes. Yet they keep adding it.

 

[JohnN]

I don't understand this.

Really easy.

 

[ssully]

FWIW I just tried this on Cross Eyed Mary quad (96kHz), and I eyeballed it (using highly magnified and if necessary amplified lowpassed LFE and FR tracks and careful time measurement within Audacity) and ended up with a 2.784 sec forward LFE offset (I.e., that much silence needs to be added to the start of the LFE). But I immediately noticed that the resulting LFE looked out of phase at a 'macro' level with the front left and right too. Anyone else see this?

 

[Dynamic Editor]

FWIW I just tried this on Cross Eyed Mary quad (96kHz), and I eyeballed it (using highly magnified and if necessary amplified lowpassed LFE and FR tracks and careful time measurement within Audacity) and ended up with a 2.784 sec forward LFE offset (I.e., that much silence needs to be added to the start of the LFE). But I immediately noticed that the resulting LFE looked out of phase at a 'macro' level with the front left and right too. Anyone else see this?

You offset the original LFE, not the low-passed LFE, right?

 

[paligap]

FWIW I just tried this on Cross Eyed Mary quad (96kHz), and I eyeballed it (using highly magnified and if necessary amplified lowpassed LFE and FR tracks and careful time measurement within Audacity) and ended up with a 2.784 sec forward LFE offset (I.e., that much silence needs to be added to the start of the LFE). But I immediately noticed that the resulting LFE looked out of phase at a 'macro' level with the front left and right too. Anyone else see this?

This is why I asked about removing/muting the LFE channel. I really appreciate DE's findings and recommendations, but they're a little complicated for this dummy, and if there is a simpler way to solve the LFE problem, I'd love to hear it.

 

[Dynamic Editor]

This is why I asked about removing/muting the LFE channel. I really appreciate DE's findings and recommendations, but they're a little complicated for this dummy, and if there is a simpler way to solve the LFE problem, I'd love to hear it.

Removing it is probably fine.