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Enoch Light – 4 Channel Demonstration

22 May

The fourth and final AM release

Enoch Light – 4 Channel Demonstration

Reference Series Releases contain:

Original EV-4 encoded Stereo file for personal decode evaluation (MLP only)

EVd decoded versions on MLP, DTS,AC-3

 

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EV-4: The Mystery Solved? – Part II

16 May

Something i should have added in the first part of my investigation is that not all of the ‘QD’ releases are subject to having been released in EV-4 and QS formats. The last EV-4 encoded release appears to have been 5051 (Enoch Light – Big Hit Movie Themes) so it’s fair to say that any album from 5052 onwards marked QD is QS.

Now i will attempt to show how it is ‘possible’ to distinguish an EV-4 encoded album from a QS one, although i must state that when it comes to QS encoded albums the pictures may not be so clear cut, the visual phase response is just a snapshot of a rather complex mathematical  equation, so if you attempt to try this method yourselves, please take your time! Hopefully you’ll see why.

Unfortunately i don’t have more than one copy of any of the Project 3 quad albums so i’m unable to show how a particular albums visual phase response difference compares between the two, but i’m sure that the two albums chosen will give an adequate picture, so to speak.

We’ll start with one of the demonstration albums that were only released using EV-4. This is the album i released a few days ago, ‘Enoch Light – 4 Channel Stereo’. The first picture shows the standard waveform of the complete album that was used for decoding purposes, and included on the release.

The next view is a snap shot of the waveforms spectral phase. It would be very easy to take too much notice of this as it only shows a visual representation of what the program sees and isn’t truly correct, but for the purpose of this experiment it will be more than adequate.

As you see, there is a large amount of zero phase information on almost every track, surrounded by large amounts of random phase information, including some small amounts of out-of-phase information on a couple of tracks.

This could be considered fairly standard for a stereo album and normal for an Amplitude Matrix system like DY and EV-4. As will be seen later, there is no evidence of any +-90 degree information above or below the zero degree line.

Now for the next album marked QD, which is ‘Tony Mottola – The Best Of’

and its spectral phase

I’m sure that you’d agree the difference is instantly obvious, there being less ‘random’ phase information and a slightly lower level of zero phase information. But more importantly there is evidence of +90 degree information on two of the tracks.

Although it is QS encoded, due to the way the audio is encoded and this being just an overview snap shot, there is no guarantee that there will always be such marked proof as shown here. Closer examination by expanding the view horizontally per track would probably show up smaller groups of ‘information’ on either the -90 or +90 degree line.

Because of this it’s not advisable to go by just one track from an album, but at the bare minimum one half of it, preferably the whole album.

To end  i’d like to re-emphasise that this issue is probably why many state that their ‘previously thought to be EV-4 album’ decodes perfectly well through a QS decoder is because it is QS.

The program i have used is Adobe Audition 3, which was once a paid for programme but has, in the last few years, been officially available as a free download. To save having multiple links i’m making the whole package (including updates) available.

 

Supersonic Quadraphonic Sound Spectacular EVd

10 May

Supersonic Quadraphonic Sound Spectacular EVd

Reference Series Releases contain:

Original EV-4 encoded Stereo file for personal decode evaluation (MLP only)

EVd decoded versions on MLP, DTS,AC-3

 

DY & EV-4/Stereo-4 Reference Decode Series

7 May

As part of the close-down of the blog i’ve been promising to release a small number of the demonstration records from the 1970’s for each of the major Quadraphonic matrix systems, which will include not only a decoded version of the album using the last of my decoding process’s, (the **d series) but also the original encoded stereo file on the DVD-A portion to allow comparisons between different methods of decoding that particular matrix system.

To start the ball rolling i’m starting with one of the two Amplitude Matrix system’s  (namely DY & EV-4/Stereo-4). Unlike the later systems SQ, QS etc, they were developed before the use of 90 degree phase shifting, so were quite basic and limited in what could be expected from them.

Firstly, it is/was impossible to decode the four channels back to their original positions using hardware decoders, instead the decoders were programmed to “create an effect” giving about 1db of rear left and right separation. This meant the encode and decode equations were completely different, something that didn’t happen once 90 degree phase came into use.

There has been much spoken about a QS decoders ability to actually decode the two AM systems, but that normally comes from those whose knowledge of matrix systems is either seriously limited or non-existent.

It does appear that most people are more than happy with some noise coming out of the rears, irrespective of whether it’s right or not. It’s more than likely the major reason why people believe they are hearing it as decoded is down to phase.

I’ve yet to read, or hear, of anyone who has gone near the subject, most probably because they a) have a good reason not to and/or b) they just don’t know.

So what do i mean? QS is, as i’ve previously mentioned, one of the Phase Amplitude Matrices, using +-90 degree phase shifting to enhance the encode/decode process. Of course, like anything matrix encoded, QS encoded material requires the inverse of the encode equation to be used during decoding, a part of which means the rears are shifted back to their original phase.

And here’s the rub. By attempting to decode DY or EV-4/Stereo-4 through a QS decoder, as well as being mathematically incompatible, the resulting rear channels are no longer on phase in releation to the front channels. Those who have heard the effect of out of phase speakers when setting up a stereo system will be well aware of the illusion of increased channel separation and space can becomes apparent, but that’s all it is, an aural illusion.

So, as well as making available these demonstration albums, i’m also making available a small script for those who use Adobe Audition v3 to allow correction to the rear channels to bring them back in phase with the fronts after using a hardware QS decoder.

This script is supplied ‘as is’, it makes no attempt to do any form of decoding, just correction. It is very small and ONLY for use on the rear channels of DY or EV-4/Stereo-4 material after being ‘decoded’ by a hardware QS decoder. I offer no help with this script, or in the use of it with Adobe Audition v3, or anything involved with Adobe Audition.

So, to the first of the three EV-4/Stereo-4 and one DY demonstration albums i plan to release:

Enoch Light – 4 Channel Stereo (EV-4/Stereo-4) New v2

Reference Series Releases contain:

Original EV-4 encoded Stereo file for personal decode evaluation (MLP only)

EVd decoded versions on MLP, DTS,AC-3

 

Tony Mottola – Tony and Strings

20 Mar

I can imagine there are quite a few who are thinking “Why’s he releasing yet another Tony Mottola album?”

Well the simple answer should be”Well it’s Quad”, but actually here in the UK we are suffering from the left overs of the snow storm that hit the USA, and it’s raining, AGAIN!

I was playing this album and thought “why should i keep this to myself, it so fit’s the mood of the day”. So here it is, something on the gentle side for those certain occasions………

Release: DS99d

Source: EV-4 LP

Process: ‘Dryad’

Format: DVD-A/V  MLP/DTS/DD

 

Phil Bodner – The Brass Ring

9 Mar

Bio/Discography

Reissue: (D) New decode

Release: DS525d

Source: EV-4 LP

Process: ‘Dryad’

Format: DVD-A/V  MLP/DTS/DD

Urbie Green – 21 Trombones

9 Mar

The track ‘The Green Bee’  was originally written by Tommy Newsom as a possible theme for the ‘Green Hornet’ TV series, but the producers went with Billy May’s theme. This was the first time Newsom’s version had been made available publicly.

Reissue: (D) New decode

Release: DS521d

Source: EV-4 LP

Process: ‘Dryad’

Format: DVD-A/V  MLP/DTS/DD

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