HiRez Poll Beck, Jeff - BLOW BY BLOW [SACD]

[edisonbaggins]

I voted 10! Watch this to discover why.

Jeff Beck ~ Blow By Blow Quad
Review + Sony vs. AP SACD Shootout!

 

[quicksrt]

You will get spectacular bass if you fix the phase problem.

Will one not get great bass by turning off the sub completely (and the center while at it) on a quad recording repurposed to 5.1? Especially if it is out of phase with the rest of the chans.
Why would bass extracted from the quad mix and sent to it's own channel be special?

 

[The Rang]

Is it feasible to intentionally reverse the wiring on some of the speakers to correct the phase issue?
And is the problem on both Sony SACDs or just the 7”
Can I assume the 2.0 is OK

 

[ssully]

Will one not get great bass by turning off the sub completely (and the center while at it) on a quad recording repurposed to 5.1? Especially if it is out of phase with the rest of the chans.

No, because the main problem is the out of phase content in the front LR vs rear LR channels. Those channels contain all the bass. The LFE in the 5.1 mix is superfluous, it duplicates bass content in the L/R, at a low level; you could omit it from the mix entirely , on uncorrected or corrected versions. (Same goes for the center channel; it contains derived, low level content present in the front L & R quad channels). Doing so (or not) won't fix the bass deficiency caused by front vs rear phase inversion.

Why would bass extracted from the quad mix and sent to it's own channel be special?

It wouldn't be. On the uncorrected mix, using just quad channels, the 'extracted' bass would still be from out of phase front vs rear channels. Still weak.

Again: no amount of LFE channel or bass management manipulation by itself will fix the phase issue. You must invert the phase of either both Front, or both Rear channels. This puts front and rear back in correct phase alignment with each other.

The inverted phase of the LFE (and center) that was created for the 5.1 mix is a comparably minor issue; you can fix that too by making sure its phase matches all the other channels -- since there is relatively little content in the LFE and C, it has little effect one way or the other -- or you can just omit the LFE and C, as they do not constitute 'discrete' content absent from the quad channels.

The AF release appears to have aligned front vs rear phase (I don't know what they did with LFE and center). That fixes the issue. Edisonbaggins's recent video make it audibly very clear what the effect is: greatly increased bass.

 

[ssully]

If you are working from ripped files, HomerJAU's amazing Music Media Helper tool lets you fix phase issues easily...and omit channels to taste. (For compatibility with quad-crippled modern AVRs, probably best to replace unnecessary 5.1 channel content with empty channels, rather than omitting them)

 

[quicksrt]

No, because the main problem is the out of phase content in the front LR vs rear LR channels. Those channels contain all the bass. The LFE in the 5.1 mix is superfluous, it duplicates bass content in the L/R, at a low level; you could omit it from the mix entirely , on uncorrected or corrected versions. (Same goes for the center channel; it contains derived, low level content present in the front L & R quad channels). Doing so (or not) won't fix the bass deficiency caused by front vs rear phase inversion.



It wouldn't be. On the uncorrected mix, using just quad channels, the 'extracted' bass would still be from out of phase front vs rear channels. Still weak.

Again: no amount of LFE channel or bass management manipulation by itself will fix the phase issue. You must invert the phase of either both Front, or both Rear channels. This puts front and rear back in correct phase alignment with each other.

The inverted phase of the LFE (and center) that was created for the 5.1 mix is a comparably minor issue; you can fix that too by making sure its phase matches all the other channels -- since there is relatively little content in the LFE and C, it has little effect one way or the other -- or you can just omit the LFE and C, as they do not constitute 'discrete' content absent from the quad channels.

The AF release appears to have aligned front vs rear phase (I don't know what they did with LFE and center). That fixes the issue. Edisonbaggins's recent video make it audibly very clear what the effect is: greatly increased bass.

forget about the LFE and center for a minute.

I assume that when Edison says he has bounced the front to the rears, I take that means he has combined the front with the rears (summed) to show this out of phase (cancelation) effect WHEN THEY ARE COMBINED.

What the effect is while listening to this in quad (as it was mixed to be played) is not a such dramatically different bass response. The very clear effect is when those channels are summed, that's when one can really discern this phase issue. This greatly increased bass (on the AP not AF btw) is not so audible when playing back both SACDs in a normal mode. So the video does not really make it clear what happens when the discs are played back normally. I did not see any demo of when the discs are played back in their normal fashion, and what the bass differences are then. So no, Edison's video does not show what the effect is listening to this program and comparing bass. You are overstating the true effect of this error. That the bass is still weak.

I might prefer the AP disc over the Sony regardless of the phase issue. So I'm not stating an opinion that the Sony is not in error. It's just that the video is not showing greatly increased bass in normal playback. Only in summing do we hear this. Unless I missed a part of the video where both are played back in a standard way, and bass is then compared. It's actually not increased bass in the AP, so much as diminished bass in the Sony (when summed)

A new video comparing the two discs is in order, playing this same section of each disc and not summing or bouncing any chans around, and just let us hear what's going on. Or comparing only the bass tracks one against the other. Then we can discern where or if any bass is missing.

 

[edisonbaggins]

@ssully and @quicksrt I agree with you both, to some extent.

Here's how I see things: the "normal playback" test has already been performed umpteen times. I see a strong consensus that the Sony mastering is "anemic," especially compared to the AP.
I have demonstrated what I strongly suspect to be the cause. Phase cancellation can occur on playback, in a room. I don't think anybody is contesting that. Sure, the effect will not be as dramatic as summing with files. If somebody would like to do a "field recording" of both versions on their system, that could be cool. But, then again, the effect wouldn't necessarily be the same on others' systems. I did not think doing such a thing would be compelling in the midst of co-review of this album.

 

[ssully]

forget about the LFE and center for a minute.

I assume that when Edison says he has bounced the front to the rears, I take that means he has combined the front with the rears (summed) to show this out of phase (cancelation) effect WHEN THEY ARE COMBINED.

What the effect is while listening to this in quad (as it was mixed to be played) is not a such dramatically different bass response. The very clear effect is when those channels are summed, that's when one can really discern this phase issue. This greatly increased bass (on the AP not AF btw) is not so audible when playing back both SACDs in a normal mode. So the video does not really make it clear what happens when the discs are played back normally. I did not see any demo of when the discs are played back in their normal fashion, and what the bass differences are then. So no, Edison's video does not show what the effect is listening to this program and comparing bass. You are overstating the true effect of this error. That the bass is still weak.

I only pointed to edison's video because he at least tried to to do a comparison that all could listen to, over headphones (afaict, he doesn't broadcast his Youtube videos in quad...). I don't need his video to 'prove' the effects of cancellation due to phase mismatch. It's physics, not imagination.

I don't own the AP; I did my own correction of the Sony. From accounts here, the mastering of the AP is essentially identical other than the phase correction. So I don't expect the results to be materially different of AP flipping the phase, or me doing it. It's easy to demonstrate any of this to yourself, if you have the uncorrected (multichannel) album as files. Keep one copy 'out of phase' and also make a 'corrected' copy of it. Pick a track, compare, switching back and forth between pre- and post-correction Switching actual discs takes too long to do a good comparison. Quick switching between files is more revealing. It's what I did. You can *measure* the effect by holding up a dB meter. Add more bass, overall level goes up. Notably so.

In a room, front and rear output are combined 'in the air'; the effect is still cancellation of the same, but out of phase, content in front and rear channels. Similarly, if you wire your front a left loudspeakers out of phase, and play almost anything recorded in stereo, you will hear a marked 'hollowing' effect...all occurring in air. You have cancelled content that is the same in L and R, except for its phase. The 'weak bass' effect in quad will be a function of bass being present in front and rear channels. I found it to be *quite* dramatic.

The front-rear phase issue is of course also apparent if you sum the bass from all channels and send it to a sub. Extremely dramatic.

In either setup (bass managed or not), the bass is very far from 'still weak' once the phase is corrected. If you're finding it so, I don't know what to tell you.

 

[quicksrt]

@ssully and @quicksrt I agree with you both, to some extent.

Here's how I see things: the "normal playback" test has already been performed umpteen times. I see a strong consensus that the Sony mastering is "anemic," especially compared to the AP.
I have demonstrated what I strongly suspect to be the cause. Phase cancellation can occur on playback, in a room. I don't think anybody is contesting that. Sure, the effect will not be as dramatic as summing with files. If somebody would like to do a "field recording" of both versions on their system, that could be cool. But, then again, the effect wouldn't necessarily be the same on others' systems. I did not think doing such a thing would be compelling in the midst of co-review of this album.

The test might have been done umpteen times - but not on a video that I have seen. I would have liked to see and hear that. Nobody is in dispute of this mastering issue.

It need not be recorded live in the field. Just a stereo line recording (or extracted tracks) that features most of where the bass is assigned on Blow By Blow. The two SACDs back to back playing stereo channels with one of the out of phase. The out of phase and anemic sounding bass (if it sounds this way) would speak for itself.

Maybe I’m the person meant to do “this” video demo.

 

[quicksrt]

Is it feasible to intentionally reverse the wiring on some of the speakers to correct the phase issue?
And is the problem on both Sony SACDs or just the 7”
Can I assume the 2.0 is OK

Yes that could be done. And yes it is in both Sony SACDs.

 

[kap'n krunch]

I voted 10! Watch this to discover why.

Jeff Beck ~ Blow By Blow Quad
Review + Sony vs. AP SACD Shootout!

MIke, you need a HAIRCUT!!!!
Clement...I just noticed , great painting in the back!

Awesome video, thanks for the shootout!

 

[ssully]

The test might have been fine umpteen times - but not on a video that I have seen. I would have liked to see and hear that. Nobody is in dispute of this mastering issue.

It need not be recorded live in the field. Just a stereo line recording (or extracted tracks) that features most of where the bass is assigned on Blow By Blow. The two SACDs back to back playing stereo channels with one of the out of phase. The out of phase and anemic sounding bass (if it sounds this way) would speak for itself.

? I'm not clear what you are proposing here. But the bass anemia comes from the front and rear channels of the uncorrected version being played simultaneously, resulting in acoustic cancellation of shared F/R bass content in the air (electronic cancellation in a subwoofer), because the shared content is out of phase.

To demonstrate conclusively, rip the uncorrected version and the AP version to files. Pick a track to use as a demo (the first one works well). Strip out the C and LFE channels from both, converting them to 4.0 (or replace them with empty channels). Set all 4 speakers either to 'large' or 'small', depending on whether you want to engage the subwoofer. A/B playback back and forth between the two versions, on the multichannel system. As an option, use a sound level meter to demonstrate the level difference that results.

 

[quicksrt]

? I'm not clear what you are proposing here. But the bass anemia comes from the front and rear channels of the uncorrected version being played simultaneously, resulting in acoustic cancellation of shared F/R bass content in the air (electronic cancellation in a subwoofer), because the shared content is out of phase.

To demonstrate conclusively, rip the uncorrected version and the AP version to files. Pick a track to use as a demo (the first one works well). Strip out the C and LFE channels from both, converting them to 4.0 (or replace them with empty channels). Set all 4 speakers either to 'large' or 'small', depending on whether you want to engage the subwoofer. A/B playback back and forth between the two versions, on the multichannel system. As an option, use a sound level meter to demonstrate the level difference that results.

My ears are good enough to hear it.

What I said is what I said. The difference in the two discs played back in the video was not a demo of what they sound like in quad. What do you not understand about that?

 

[MidiMagic]

Knowing the SQ matrix, I know that there WILL be a bass difference front to back.

The bass on an SQ record MUST be at front center or it would not work on a phonograph record.

Anything that appears at front center in SQ (and also RM) will be in phase LF to RF in the front speakers and out of phase LB to RB in the back speakers. There is an odd-angle phase shift front to back in SQ.

Summing all four channels to get the bass is a mistake with any matrix system except BMX.

 

[sjcorne]

The bass on an SQ record MUST be at front center or it would not work on a phonograph record.

There are quite a few SQ LPs where the bass guitar is isolated in one of the rear channels. Sly & The Family Stone’s Greatest Hits and Return To Forever’s Musicmagic come to mind as two examples.

 

[fredblue]

There are quite a few SQ LPs where the bass guitar is isolated in one of the rear channels. Sly & The Family Stone’s Greatest Hits and Return To Forever’s Musicmagic come to mind as two examples.

indeed! as we know, at one point (74-77) any number of CBS SQ Rock & Pop mixes not attributed to any of their regular Quad engineers (Keyes, Young..) had Bass in the Rear Left (Minnie Riperton, Dan Fogelberg, Return To Forever, Tower Of Power).

based on the information that's come to light in the last few years since Dutton Vocalion started doing Quad, many of these have been surmised in all probability to have been the work of A&M's Dick Bogert & Warren Vincent, real pro's who to my mind wouldn't have knowingly mixed anything that would've been incompatible with SQ LP.

 

[quicksrt]

I thought that the main drawback with SQ is very poor separation in rear channels? Even if it has elements mixed hard L or R in rears if never played back that way? And that it never will regardless of the mix choices. No?

 

[sjcorne]

I thought that the main drawback with SQ is very poor separation in rear channels? Even if it has elements mixed hard L or R in rears if never played back that way? And that it never will regardless of the mix choices. No?

Going off-topic here, but it depends on how the instrumentation is panned and what decoder you use. Elements isolated in one speaker can sound very discrete with a Tate, Surround Master, or Audition Script. Centered elements such as vocals or guitar solos are more hit-or-miss. You really start to run into trouble with stereo images - drum kit or piano mixed across the front channels, for instance. Those really bleed into the rears, often to the point where you can't tell where they're actually supposed to be coming from. Earlier wonky 4-corner mixes like Sly's Greatest Hits are fairly well-represented in SQ (with a good decoder), but later mixes that utilized stereo images like The O'Jays' Family Reunion can sound almost nothing like the discrete versions.

 

[Philip Spinner]

indeed! as we know, at one point (74-77) any number of CBS SQ Rock & Pop mixes not attributed to any of their regular Quad engineers (Keyes, Young..) had Bass in the Rear Left (Minnie Riperton, Dan Fogelberg, Return To Forever, Tower Of Power).

based on the information that's come to light in the last few years since Dutton Vocalion started doing Quad, many of these have been surmised in all probability to have been the work of A&M's Dick Bogert & Warren Vincent, real pro's who to my mind wouldn't have knowingly mixed anything that would've been incompatible with SQ LP.

You are right about there being many quads with bass in the rears. Back in the 70's I marked every quad tape that had bass in the rear for car use. There are hundreds mixed that way on all labels. Perhaps some of these mixers that you so graciously prepared a list of had quad in their own cars and were secretly mixing these to sound good while driving around.

 

[Clement]

MIke, you need a HAIRCUT!!!!
Clement...I just noticed , great painting in the back!

Awesome video, thanks for the shootout!

I could use a shave, actually. I'm so glad you noticed the painting (how could you not!?)--one of my prized possessions. A very sad story behind it. Maybe I'll tell it one day. The painting is titled "Seven Seconds Fast." It's 47" x 80" The artist is no longer with us, but he lives on in his Art. Murf. RIP

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