ANALOG Channel Reassignment Recommendations

[himey]

Harvest was my first DVD-A purchase ten or more years ago, I have always liked the channel alignment. I am in the middle of the room with the band playing around me, different sounds coming out of different speakers, surround sound as it were. I can't hear a problem with the mix, same goes for TYA Space In Time as long as all speakers are active, different sounds coming out of each I'm happy, but that's me.

If you look at the spectrum graphs it is easy to tell they screwed up the channel assignments. It sounds much better once you correct the channels. Did you listen to this with the channels corrected and then compare?

 

[skherbeck]

I've tried all the channel reassignments mentioned so far on the QQ... Ten Years After, Harvest, Freehand (by far the most difficult due to the level adjustments necessary after changing the channels), even "Wouldn't It Be Nice" from Pet Sounds, and they have all worked perfectly! Highly recommended and not too difficult (I'm not an engineer or a computer guy!) Try it... It pays huge musical dividends!

 

[neil wilkes]

If you look at the spectrum graphs it is easy to tell they screwed up the channel assignments. It sounds much better once you correct the channels. Did you listen to this with the channels corrected and then compare?

According to the story I have heard, "Harvest" was done the way it is quite deliberately, as the whole intention was to sit you in the rehearsal circle the musicians were in.
I'm pretty certain it's discussed in one of the accompanying extras on the disc - but am totally sure it is meant to be how it is.
This is not to say you cannot reassign if you choose to though, or that reassignment will not improve things. (not tried it, and it may well give a different balance but it does not mean it is the intended balance)

The TYA DVD is simply reversed - front for rear.

Aretha's mix? Believe me it's not as bizarre as some! I remember going through some Q8 of Azteca & Sly & family stone and some mix decisions were truly bizarre and I think the conclusion above that there were no conventions at this point & the mixers were scraping it off the wall as they went along is about right. There are mixes with all drums in one rear speaker, bass in one front one (no phantom centre used anywhere).
All very weird.

 

[himey]

According to the story I have heard, "Harvest" was done the way it is quite deliberately, as the whole intention was to sit you in the rehearsal circle the musicians were in.
I'm pretty certain it's discussed in one of the accompanying extras on the disc - but am totally sure it is meant to be how it is.
This is not to say you cannot reassign if you choose to though, or that reassignment will not improve things. (not tried it, and it may well give a different balance but it does not mean it is the intended balance)

The TYA DVD is simply reversed - front for rear.

Aretha's mix? Believe me it's not as bizarre as some! I remember going through some Q8 of Azteca & Sly & family stone and some mix decisions were truly bizarre and I think the conclusion above that there were no conventions at this point & the mixers were scraping it off the wall as they went along is about right. There are mixes with all drums in one rear speaker, bass in one front one (no phantom centre used anywhere).
All very weird.

Try it and then give us your opinion. It sounds very bad the way it was released. I can't imagine that was what they were going for.

 

[skherbeck]

According to the story I have heard, "Harvest" was done the way it is quite deliberately, as the whole intention was to sit you in the rehearsal circle the musicians were in.
I'm pretty certain it's discussed in one of the accompanying extras on the disc - but am totally sure it is meant to be how it is.
This is not to say you cannot reassign if you choose to though, or that reassignment will not improve things. (not tried it, and it may well give a different balance but it does not mean it is the intended balance)

The TYA DVD is simply reversed - front for rear.

Aretha's mix? Believe me it's not as bizarre as some! I remember going through some Q8 of Azteca & Sly & family stone and some mix decisions were truly bizarre and I think the conclusion above that there were no conventions at this point & the mixers were scraping it off the wall as they went along is about right. There are mixes with all drums in one rear speaker, bass in one front one (no phantom centre used anywhere).
All very weird.

After doing the reassignments, the mix and placement of instruments within the mix is consistent throughout the entire disc... it really sounds like it was meant to be this way... but who knows.

 

[skherbeck]

Talking about Harvest!

 

[himey]

After doing the reassignments, the mix and placement of instruments within the mix is consistent throughout the entire disc... it really sounds like it was meant to be this way... but who knows.

It's pretty obvious they got the channels wrong on the Harvest disc. Like you said, it becomes consistent throughout the disc once you rearrange the channels on the songs that are messed up.

 

[himey]

So a couple of years ago I said this:



More recently I've been ripping my entire collection to FLAC including DTS DVD-Vs and it was always my intention to rip this and discard the center channel. So while I was doing that I had a look at the whole thing to check for phase errors, channel assignment problems etc.

What I found (in a nutshell, more detail below) is the following:

1. The center channel was created by duplicating the front left channel (only), applying an 80ms delay and then adding an EQ boost of a few dB to it from about 100Hz up to 2500Hz. The result is that the center channel sounds a bit like a loudspeaker at a shopping mall or something, and the delay between it and the FL channel causes all kinds of weird phase issues - the phase meter i was using was fluttering back and forth like it was having a seizure or something. Normally fake center channels are created by summing the front left and right channels and then reducing the volume of the resultant derived channel, so the way they've done it here is odd to say the least. Also, with the EQ boost on the center channel it effectively makes it the loudest/most dominant channel in front of you and collapses the stereo image in to the middle - this album sounds so much better with it gone.

2. The LFE channel is out of phase (!) and way way too loud. My supposition is that because the LFE was out of phase, the more they turned it up, the more it was cancelling out the bass in the 4 main channels. So as a result they just kept cranking it up until it reached some kind of point of equilibrium, because when I corrected the phase of the LFE I had to turn it down by 20 (TWENTY) dB. There's actually nothing unique in the LFE channel (ie they didn't shave any bass off the main channels) so if you want to delete the LFE track entirely you can. I chose to keep it because even with large speakers, I think it's nice to have a little something coming out of the subwoofer if you have your speakers set to large. The 20dB reduction was just done by ear and looking at waveforms (and based on the LFE levels in other .1 tracks I've seen) so it may not be perfect, but it's in the ballpark.

3. The track index points are wrong for every single track (and by different amounts for each track) so the net result is that the first 2 or 3 notes of each song is cut off, instead appearing at the tail end of the track before. I imported all the songs in to my workstation as one long track and re-exported them so the tracks were split correctly. If you want to do this too, the track timings are as such:

Track 1: 00:00.000
Track 2: 04:06.350
Track 3: 08:32.000
Track 4: 13:03.000
Track 5: 18:10.600
Track 6: 21:30.000
Track 7: 24:56.350
Track 8: 29:23.000
Track 9: 33:37.000

Everything else checks out though, the channel assignments are correct, everything (else) is in phase, and it doesn't look like they compressed it much if at all - the DR readings are between DR11 and DR13 which puts it close to even the unremastered 80's CD issue. I'm not overly in love with the EQ - it's a little midrangey and the treble falls off steeply around 15kHz but it's probably as good as it gets for standard DTS. I'm still experimenting with EQ for this album but i think if you take a little bit out between 1kHz and 3kHz it might help a bit.

Here are a couple of screenshots that illustrate the problems I was explaining earlier:

Fig 1. showing that the center channel waveform is identical to the front left

(the red line shows where the identical time-offset peaks start)

View attachment 25818


Fig 2. showing the weird midrange boost on the center channel

(The green waveform is the front left channel, and the pink bits that stick up between 100Hz and 2500Hz are the center channel, showing where it's boosted relative to the front left.)

View attachment 25817


Fig 3. showing how LOUD the LFE track is relative to the other channels

View attachment 25819


I didn't do a screenshot of my phase meter showing that the LFE was out of phase, but you can take my word for it that it was. The phase meter goes from -1 (out of phase) to 0 (no phase correlation at all) to +1 (in phase) and the LFE track was consistently at -1 with no movement at all.

One last note, I don't think Glenn Hughes did the quad to 5.1 mix, he supervised the remixing of the bonus tracks on the stereo CD. I believe Peter Mew did the quad to 5.1 transfer which would probably explain a lot of the problems.

Bumping this with info on how to repair Stormbringer. This turns a crappy dvd into a very nice quad mix. Thanks Steelydave!

 

[HomerJAU]

Just caught up on this thread. Thanks for the info.

I just did Neil Young - Harvest as recommended on this thread

plus:

The Isley Brothers - 3 + 3 (swap rears (LR to RR and RR to LR)
The O'jays - Ship Ahoy (swap rears (LR to RR and RR to LR)

As recommended in the 3 + 3 poll thread

I used a small Windows command line utility named Sox and a batch file to remix all songs in each album folder:

(You can download SOX from here: LINK Just copy all the files into a new folder on your PC - Sox is also in my Media Manager app posted on the QQ Media Player section)

Create a Swap.bat (text) file in your folder containing your flac wav files to correct and add this text:
----

if not exist "Output" mkdir "Output"

for %%A IN (*.flac) do (
"C:\xxx\xxx\Sox.exe" "%%~nA.flac" "Output\%%A" remix 1 2 3 4 6 5
)
pause

-----
Replace the C:\xxx\xxx\ with the path to your folder with Sox.exe file then save.

When you run the bat (double click) it will auto find all flac files (*.flac) in the same folder as 'Swap.bat' and creates an 'Output' folder, converting each original flac to the corrected flac in Output.

NOTE: The above swaps rear channels for 3+3 and Ship Ahoy (to do Harvest replace the channels assignments after remix with: 5 6 3 4 1 2

Channels in remix are always in order: LF RF C LFE LR RR
The 'remix' command always specifies in the output channel order. But each channel number refers to the input channel. So above 1 from input in 1 Output... (last one is) Ch 5 from input into 6 output

Another example: If you have a '5 Channel Quad' source (e.g a Quad SACD with silent centre) then you could remix into quad with remix 1 2 4 5

 

[sjcorne]

Just caught up on this thread. Thanks for the info.

I just did Neil Young - Harvest as recommended on this thread

plus:

The Isley Brothers - 3 + 3 (swap rears (LR to RR and RR to LR)
The O'jays - Ship Ahoy (swap rears (LR to RR and RR to LR)

As recommended in the 3 + 3 poll thread

Harvest I agree with, but I really think the O'Jays and Isley albums are supposed to be that way. I just got the Ship Ahoy SQ LP and the intro to "For The Love Of Money" pans diagonally from RF to RL. I remember seeing an old thread regarding philly soul quad mixes and the use of diagonal panning (despite the rules of SQ).

Also, AF had the opportunity to correct the channel assignments for the tracks from those albums on The Collection and they didn't, so that could mean something. But the fact does remain that diagonal panning was not an encouraged mixing technique for SQ. This has been debated for quite some time and will likely continue to be...I just wish someone would just come forward with Q8 waveforms to provide a more definitive answer. Honestly to me they sound fine either way.

Some other important channel-swapped discs:
Ten Years After- A Space In Time EMI DVD fronts and rears swapped
Ditto on the two quad GG albums

One I've never been sure of...DP Machine Head UK quad SACD. Rears are swapped compared to SQ disc so something doesn't match. Maybe the SQ was wrong? As with the two Philly Int'l discs it sounds fine either way.

Don't even get me started on GRT Q8s...

 

[HomerJAU]

Harvest I agree with, but I really think the O'Jays and Isley albums are supposed to be that way. I just got the Ship Ahoy SQ LP and the intro to "For The Love Of Money" pans diagonally from RF to RL. I remember seeing an old thread regarding philly soul quad mixes and the use of diagonal panning (despite the rules of SQ).

To me this sounds much nicer with the circular pan after the fix suggested.

 

[fredblue]

the diagonal pans on the Ship Ahoy Quad are correct, no channel swap is required.

steelydave has the info on the Philadelphia International labels' engineers' intentional use of diagonal pans in their Quad mixes.

 

[fredblue]

To me this sounds much nicer with the circular pan after the fix suggested.

the bass line bounces 'correctly' round the room when you swap the rears but the vocal effect then becomes zig zagged rather than sweeping clockwise 360 round the room and that sounds weirder, to me, when changed.

knowing that other PIR label Quads have diagonal pans (MFSB's Love Is The Message is full of the effect, in fact drums are diagonally positioned throughout) and had it confirmed by steelydave who got the info from one of the Philly Int'l Quad engineers that PIR implemented diagonal pans in their Quads for effect (i think to create a pseudo phantom centre in the middle of the soundfield, a no-no ordinarily with SQ as when the same sound bursts simultaneously in all 4 channels it cancels out) i firmly believe the Ship Ahoy Quad mix as it is similarly presented on the Sony SACD, the decoded SQ LP and that track on the AF SACD, has correctly assigned channels and needs no correction.

 

[steelydave]

As Adam said, and I mentioned in another thread a while back, I've been speaking to Arthur Stoppe, who started at Sigma Sound as an assistant engineer in 1973. He assisted on all the PIR quad mixes (as well as the Spinners CD-4 quad mixes) and quickly became Sigma's go-to guy when it came to quad mixing, because he learned about all the technical limitations of SQ matrix quad. By 1975 he was Sigma's main quad engineer and did the final quad mixes competed at the studio, including MFSB's 'Philadelphia Freedom' and The O'Jays 'Family Reunion' in 1975, and Harold Melvin & The Bluenotes 'Wake Up Everybody' and The O'Jays 'Message In The Music' in 1976.

I'll include some quotes from Arthur below, but in a nutshell I have to eat a whole lot of crow, because I was wrong about the diagonal instrument and vocal placement being a mistake - at least in the case of the Philadelphia International quad mixes.

The purpose of these 'diagonal pans' is indeed to create a phantom center in the middle of the room, or "quad center" as Arthur calls it, within the limitations of SQ. The conventional way to place something at quad center is to put it in equal power in all 4 channels, and you see this often with lead vocals in quad mixes done where there aren't any matrix limitations, like the stuff from RCA, W/E/A, and all the tape-only mixes done for Ampex. However with SQ, you can't have identical content in the two rear speakers at the same time (which you'd obviously need if you wanted to have identical content in all 4 speakers) so the MacGyver-ed solution was the diagonal placement - it would (sort of) put the sound in the middle of the room without breaking the rules of SQ.

It's worth noting, as well, that (at least in the mixes I've heard) when they used this diagonal 'quad center' method, it was to put a mono sound in the middle of the room - for example on Ship Ahoy they use it to put the bass guitar in quad center on a couple of tracks, and the bass voice on a couple of tracks (most notably on 'Don't Call Me Brother'). They don't use it for any diagonal stereo mixing, ie. you don't get half a drum kit (or horn section) in the front left and the other half in the rear right.

This is what Arthur had to say:

In SQ the only “legal” method for placing something in quad center was the diagonal left front/right rear or right front/left rear. We used to do that a lot with the bass or kick drum.

What you wanted to avoid was common mode material in the two rear channels. Since the SQ encoding phase shift between the two rear channels was in the opposite direction, if you had something panned center rear the two channels would be totally out of phase and would cancel in mono and sound really weird in stereo. But the big problem would be that that any common material between the two rear channels would, due to the 45/45 stereo system for LP (which actually cuts the two channels out of phase so that any common front channel material cuts as pure side-to-side modulation) caused pure vertical modulation in the groove of the cut record. And since there’s only so far up or down the stylus could move without either lifting off the surface or diving into the aluminum substrate of the master lacquer disk, that was a huge no-no. If you had a stereo element in your mix, –say a drum kit or grand piano, it had to be panned across the front two channels, –not the back channels.

At first, in order to maximize the apparent separation in an SQ quad mix the “experts” said you should only pan to the four corners or center front. Later on they got a bit more liberal with things, so you could have stereo material panned anywhere across the two front channels. But center rear was still off limits for the reason of it causing excess vertical modulation in the record groove.

I have to say that personally I don't really love this approach - it kinda works if you're sitting right in the sweet spot, but if you're near the back, or to one side, the soundfield gets confusing. But understanding the philosophy behind it, and the limitations of the SQ format, means it makes a lot more sense. Even 40 years after the fact, Arthur's memory about these things is strikingly clear so I have no problem at all accepting his account as definitive. In fact, when I originally contacted him I didn't realise how central he was to Sigma's quad output - I was just hoping he'd have some vague memories - but it turns out there was no one more involved with quad at the studio than he was.

 

[fredblue]

It's worth noting, as well, that (at least in the mixes I've heard) when they used this diagonal 'quad center' method, it was to put a mono sound in the middle of the room - for example on Ship Ahoy they use it to put the bass guitar in quad center on a couple of tracks, and the bass voice on a couple of tracks (most notably on 'Don't Call Me Brother'). They don't use it for any diagonal stereo mixing, ie. you don't get half a drum kit (or horn section) in the front left and the other half in the rear right.

Thanks for all the cool info, Dave, to have the definitive word on it from the horse's mouth is great and much appreciated

fwiw there's diagonal drums in MFSB's Love Is The Message Quad, I thought it was a mistake when i first noticed it but knowing now what you have discovered from Arthur Stoppe, I guess it must be intentional.

there's some dramatic synth sweeps that pan across diagonally in the title track of Billy Paul's War Of The Gods alongside 360 pans that also occur in that same track and diagonals are evident in the same tracks where there are 360 pans in a couple of songs on the Harold Melvin's Black & Blue Quad (i forget the tracks now but i will check at the weekend) i love love LOVE these PIR Quads! they are among the best Quad mixes i've yet to hear and hope they get reissued someday.

 

[DuncanS]

Diagonal pans would work well for basic SQ decodes, as the Front-to-Back separation was 'poor', at least it was on the non-Logic SQ decoder I built all those decades ago! So it would be noticeable say going LF->RB much more than LB->LF.

the diagonal pans on the Ship Ahoy Quad are correct, no channel swap is required.

steelydave has the info on the Philadelphia International labels' engineers' intentional use of diagonal pans in their Quad mixes.

 

[Fourplay]

I've been speaking to Arthur Stoppe, who started at Sigma Sound as an assistant engineer in 1973. He assisted on all the PIR quad mixes (as well as the Spinners CD-4 quad mixes) and quickly became Sigma's go-to guy when it came to quad mixing, because he learned about all the technical limitations of SQ matrix quad. By 1975 he was Sigma's main quad engineer and did the final quad mixes competed at the studio, including MFSB's 'Philadelphia Freedom' and The O'Jays 'Family Reunion' in 1975, and Harold Melvin & The Bluenotes 'Wake Up Everybody' and The O'Jays 'Message In The Music' in 1976.

This is great and useful information! Thanks so much for sharing. If you have not already, perhaps you could invite him around for some Q & A in the industry section of the forum...

Great work SD!

 

[ssully]

As Adam said, and I mentioned in another thread a while back, I've been speaking to Arthur Stoppe, who started at Sigma Sound as an assistant engineer in 1973. He assisted on all the PIR quad mixes (as well as the Spinners CD-4 quad mixes) and quickly became Sigma's go-to guy when it came to quad mixing, because he learned about all the technical limitations of SQ matrix quad. By 1975 he was Sigma's main quad engineer and did the final quad mixes competed at the studio, including MFSB's 'Philadelphia Freedom' and The O'Jays 'Family Reunion' in 1975, and Harold Melvin & The Bluenotes 'Wake Up Everybody' and The O'Jays 'Message In The Music' in 1976.

I'll include some quotes from Arthur below, but in a nutshell I have to eat a whole lot of crow, because I was wrong about the diagonal instrument and vocal placement being a mistake - at least in the case of the Philadelphia International quad mixes.

The purpose of these 'diagonal pans' is indeed to create a phantom center in the middle of the room, or "quad center" as Arthur calls it, within the limitations of SQ. The conventional way to place something at quad center is to put it in equal power in all 4 channels, and you see this often with lead vocals in quad mixes done where there aren't any matrix limitations, like the stuff from RCA, W/E/A, and all the tape-only mixes done for Ampex. However with SQ, you can't have identical content in the two rear speakers at the same time (which you'd obviously need if you wanted to have identical content in all 4 speakers) so the MacGyver-ed solution was the diagonal placement - it would (sort of) put the sound in the middle of the room without breaking the rules of SQ.


It's worth noting, as well, that (at least in the mixes I've heard) when they used this diagonal 'quad center' method, it was to put a mono sound in the middle of the room - for example on Ship Ahoy they use it to put the bass guitar in quad center on a couple of tracks, and the bass voice on a couple of tracks (most notably on 'Don't Call Me Brother'). They don't use it for any diagonal stereo mixing, ie. you don't get half a drum kit (or horn section) in the front left and the other half in the rear right.

OK, but on a truly discrete presentation, like the DVD-A and the track on 'The Collection', it doesn't end up sounding at all like a mono 'quad center'. My seat is in the 'quad center' (equal real or virtual distance from the four quad speakers, whicha re level matched). THe opening of 'For the Love of Money' sounds like....bass zigzagging diagonally. Highly directional.

 

[Fourplay]

THe opening of 'For the Love of Money' sounds like....bass zigzagging diagonally. Highly directional.

Presumably because the track is no longer mediated through the limitations of the SQ encode and decode process. The mix was created with these limitations in mind. They probably "tested" the mix by encoding and decoding with two channel tape before pressing the vinyl. Remove the process and you hear the underlying and accurate mix that was used to achieve the final decoded effect.

My question would be this: was the same mix used for the 8 Track? The quad discography lists Ship Ahoy. Philidelphia International ZAQ-32408 (DQ8), and this was therefore a discrete quad mix. I do not have a transfer of the Q8. Knowing the tape would not be encoded and decoded, did they use the same mix as what came out on the SACD?

 

[fredblue]

the zig-zagging of the bassline is jarring and weird and doesn't create a phantom centre effect, however i suspect it was another PIR Quad stylistic thing as other PIR Quads do this including a couple of Harold Melvin 4-ch mixes where rather than pop up in a 360/circle arrangement in turn as one would expect, the elements zig-zag. i will set aside some time over the weekend to check and post back with the exact instances where this zig-zagging happens. with permission i could put up a couple of v.short clips or something to demonstrate what i'm on about?

not sure i've mentioned it before but if you follow the "for the love of money" vocal refrain (with the phase-y effect on it) around the channels, it swooshes around the room from channel to channel in the more customary 360 direction/fashion (clockwise in this instance) even though the bass zig-zags about the channels within the same mix and channel assignment thereof.