Upmixing - where are we at? Have people compared upmixers?

[Newman]

I would like to agree. But one does not exist without the other, that's Toole's "circle of confusion".
With mastering, loudspeaker setups and levels aligned, there is a good chance to reproduce initial intent.
I should have better restricted my point to stereo music and 2-ch film upmixing.
From my observation, center extraction is not stable, not in level, nor in spread.
Upmixing in my HT with a now center-less layout does not suffer from this.
>Centre speaker allows correct frequency response.
Flat with one speaker and one ear/mic in an anechoic room?

Flat like a human head facing a musical instrument. No coincidence.

See attached picture from the book Floyd Toole: Sound Reproduction - Loudspeakers and Rooms.
Dialog realism with a center speaker can be "greater", because a speaker's directivity resembles a human speaker's directivity (ibid).

Correct.

Not so for instruments.

Yes, for instruments too.

>“Boxier” is too undefined to even discuss. The reason you gave makes even less sense.
Boxier here meant recognizable as coming from a loudspeaker.
Due to a loudspeaker's directivity rising with frequency, it is easily distinguished from a natural sound source not having such directivity.

Some natural sound sources may have constant directivity (maybe thunder?), but most musical sound sources do have directivity rising with frequency.

See attached picture from the book Floyd Toole: Sound Reproduction - Loudspeakers and Rooms.

I can easily recognize the center speaker's distance.
One could then argue over "You are there" vs. "They are here" type realism.

Back to the music..

Exactly. See above.

 

[Miker 1102]

I think it's been generally well accepted fact by now that Auro 3D is the ultimate upmixer. it's evident from the fact that despite having minimum native releases outside Europe all AVR manufacturers are clamouring to get Auro 3D in there AVR because of the Automatic upmixer. seems now they are getting into streaming too with some sound bar lanches. it's becoming a household name and is essentially now the most demanded feature in an AVR.

I like auro 3D the most for what I listen to which is Rush, Yes, Led Zeppelin...

 

[Miker 1102]

Matter of taste I guess, but for music I prefer Auro 2D over DSU. DSU, in my opinion, puts too many objects behind me in the L/R surrounds that I feel should be in front of me.
Auro 2D puts reverb/echo/'room volume' behind me while keeping the source at the front 'stage'.

I use Auro 2d a lot and boost the surrounds as they are all KefQ series.

 

[keks8430]

If you need a loudspeaker layout which gives spatial involvement and works equally for multi-channel film and stereo, 4.x or other center-less layouts might have their place. Works perfectly for me.

My possibly special use case is to have good sound and dialog across 2ch/DD2ch/DD5.1 from satellite TV without adjusting settings.

Found a crucial setting with Center Spread off.
With DD surround and Center Spread on, sound could get phasy or hollow.
All good and stable with center speaker now.

 

[Magnus]

If you have identical mains properly set up and aligned, you don't really need Center Spread.

CS is really there to make inferior "center channel speakers" sound better by mixing in the better quality L/R Mains.

I have identical LCR here and the setting sounds the same from the MLP with it it on or off and definitely worse off-axis due to it pulling to the closer speaker (Haas/Precedent Effect).

In fact, I see zero point in having the center speaker on for music at all if you're just going to mix in the mains. I suppose there's less Precedence pull than none, but it's still pretty bad off-center, IMO.


As for upmixers, I've been playing with a Lexicon MC-1 plugged into my Marantz 7012's 7.1 inputs (the 8015 is the last model to feature 7.1 inputs and it's on sale right now as it's being replaced by the Cinema30) and all I can say is Logic 7 blows the pants off everything out there when it comes to 2-channel to 7.1 upmixing.

You never knew what PLII was going to do with music. Some albums sounded interesting, but most just sounded odd, IMO while Logic 7 almost never sounds odd or bad. I disagree it's just ambience. I'm getting pretty 3D sound with some albums like Tori Amos' Ocean to Ocean, particularly if I add side heights to mirror my front stage "lift" effect at the sides too.

I use "Scatmos" to extract front wides and ss#2 (which also works with the Lexicon)(as well as full Heights+Tops using reverse polarity extraction on a couple of Marantz NR1403 half-height AVRs) and setting the Yamaha HTR-5960 (front wide extraction AVRs) to "Neural Surround" decoding while leaving the arrayed copies pure (Y-splitter before the extraction AVRs) gives this incredible vertical image spread very similar to what Neural X does with movies. I think the two are related as DTS bought Neural Surround and then developed Neural X next. In Star Wars (2-channel 1977 Dolby Surround track), the bits where C3P0 looks up and asks what was that imaged at ear level before, but with this effect, it images high while other sounds image low just like with Neural X. Neural X is probably more accurate, but it doesn't work with 2-channel sources very well, IMO so this offers a nice alternative. DSU is somewhat better, but it just sucks with 2-channel music, IMO.

Overall, I find Logic 7 to be the perfect balance between ambience and upmixing for 2-channel sources. It does pretty well here with 5.1 sources as well (Toy Story 2 where Al from Al's Toy Barn runs down the left wall saying, "Buck Buck Bucks" and laughing moves smooth as silk here with Logic 7 down the left wall and over to the center rear. With THX EX (really DTS-ES matrix), it moves part way down and then "jumps" over to the rear center as it's mono. With Logic 7, it's one smooth motion. Neural X can achieve the same effect here with front wides and ss#2 extracted, but it's impressive that technology from 1999 can manage 75% of the Atmos effect (Neural X maybe 90%). But for 2-channel, it just can't be beat, IMO.

Auromatic is OK for music upmixing, but you have to crank the mode and adjust the increased bass (amazing they couldn't figure out how to do that automatically in the driver; that blows my mind as it's so amateurish), but it's really just an ambient copy/reverb mode. It doesn't "move" anything whereas Logic 7 does (maybe not as violently as PIIx did, but then PLIIx was hit and miss with music, IMO as it can move things you expect in the front to the sides or rear sometimes). Part of Logic 7's appeal is that it doesn't move the front soundstage at all and it's more gentle with out-of-phase effects.

Given the combined Neural Surround with Front Height and Surround Height matching and Logic 7 along with Scatmos Front Wide & SS#2 here giving me essentially 15.1-channel Logic 7 (aka Logic 16), it's hard to comprehend why HK has had so much trouble getting Logic 16 to work properly. I think I get the full intended effect here using technology no newer than 2005 (the Yamaha Neural Surround upmixers) beyond the Marantz 7012's "7.1 input" mode to host it within my Atmos/X/Auro-3D system.

I could still add Pro Logic II (either by getting a used MC-12 or using my existing extra Yamaha HTR-5960 AVR (same ones used for front wide extraction with its Neural Surround mode), but that would mean I'd have to ditch my trusty old laserdisc player to make room for it (whereas the MC-1 fits nicely on top of it). But the Yamaha has its own 7.1 input mode, so technically I could keep the MC-1 and have both plus the Neural Surround mode, but I'd need to duplicate the Nvidia Shield digital outputs for the best connection to both (I could easily do a RCA split to both as I already have RCA into the MC-1 for the Panorama mode and DSP modes as they require either analog or 44.1kHz inputs and KODI on Android Nvidia Shield doesn't like to do 44.1kHz output without a fight. It was easier to just throw some analog connections in as well from the device extracting the digital toslink output). But frankly, I'm quite pleased with Logic 7 for 2-channel music and movies.

As for room correction, the key is to go external with a Mini-DSP. It can control 4 subs instead of the 7012's two or three plus a seat shaker output. I'm not a big fan of correction above Schroeder anyway so it works quite well.

My Home Theater Racks are shown below (The Lexicon MC-1 sits just below the Marantz 7012; the NR1403 units are on the 1st rack and the Yamaha HTR-5960s are in the right rack with Onkyo-ES600 units for SS#2 on the bottom below each rack). I've got the Nvidia Shield and Zidoo X9S both going to the Lexicon MC-1 (optical and RCA) as well as to the Marantz 7012 (HDMI). I could plug the LG Blu-Ray player into the Lexicon as well via its optical jack, but I almost never use it so I haven't bothered. The laserdisc player has only one optical output so it's connected to the 7012 for the occasional DTS laserdisc, but it has a 2nd set of RCA outputs that can be sent to the Lexicon as well as the old GameCube, which benefits from Logic 7 as well; the PS4 goes to the 7012 via HDMI).

There's also some Monoprice impedance matching switches on the right top that let me copy rear heights to surround heights and some other neat tricks. Auro-3D has the Tops speakers carrying the VOG dual mono signal in quad while front/rear heights handle the rest with optional surround heights arrayed from the rear height signals. In total, there's 21 speakers connected (11.1.10 in a 12'x24' room with 3 rows of seats). I plan ot try some floor effects next once I get one more set of PSB speakers in using the Front Wide extraction surround outputs (out-of-phase ambience will go to the floor instead). That should give a more spherical soundstage instead of a dome.

 

[dlaloum]

If you have identical mains properly set up and aligned, you don't really need Center Spread.

CS is really there to make inferior "center channel speakers" sound better by mixing in the better quality L/R Mains.

The joys of rooms and speaker variability - I have high quality matched L/C/R (Gallo Nucleus Reference 3.2 Mains, Gallo Nucleus Reference AV Center).

Primary difference between the center and the mains is the absence of the woofer - the mids and tweeter are identical (save for orientation obviously)

Center spread is definitely better in my setup - and although it varies depending on the recording, I find 3 channel DSU mixed stereo to be superior to straight stereo in most cases...

But this is from the perspective of a "wide" listening position (anywhere on a 3 seater couch) - not from a head in a vice, solo listening seat...

One of the benefits of a center channel for "stereo" (stereo in its original meaning - as in providing a 3D solidity) - is that it stabilises the virtual "image" (ie: makes the illusion work, through a wide listening area)- which is why as originally proposed in the early 20th century it was a 3 speaker/3 channel system!

 

[Magnus]

One of the benefits of a center channel for "stereo" (stereo in its original meaning - as in providing a 3D solidity) - is that it stabilises the virtual "image" (ie: makes the illusion work, through a wide listening area)- which is why as originally proposed in the early 20th century it was a 3 speaker/3 channel system!

Yes and Center Spread is actually working against that stability by mixing the center speaker contents back into the L/R mains, largely defeating the entire point of a center speaker, which is to stabilize the center for off-axis seating.

In other words, Center Spread is doing exactly the opposite of the purpose of the center, making it less stable and this is mostly to favor better sounding speakers because "most" home theaters apart from sound bars use different mains from the center.

That is why I think you might as well just use stereo, which will completely eliminate the poor sounding, often poorly placed center channel speakers people tolerate in order to have the largest screen possible in a given room (Or in the old days, there simply wasn't room underneath console TVs, rear projectors and other furniture for full sized towers or even bookshelf speakers). I mean why play music off that speaker at all when the mains are so much better sounding and at the proper height?

The only reason to use the center speaker at all is stability for off-axis seating, IMO. Otherwise, phantom works fine for a single listener.

These less than ideal center speakers are then often placed near the floor, for god's sake, so the screen can go even bigger. It's awful in a sense, really, but most people just don't give a monkey's flying excrement about sound compared to having truly gargantuan screens (or at least putting most of their budget into the biggest screen they can afford at the cost of everything else (sound, room treatments for sound, etc).

Most people are visually oriented. Sound is usually an after thought (hence the popularity of sound bars and using TV speakers, even though they've only gotten worse as TVs have gotten flatter).

And if it's not just an afterthought, it's often because they want 12 subwoofers that can play flat to 8Hz and shake their fillings loose, despite the fact no orchestra on earth has the equivalent of a +25dB shelf filter centered on 15Hz.... I have a friend into that sort of thing with 12 24' subs for infrasonics alone (I don't visit him as I'd care for my hearing to still function when I'm 70).

Some talk about smaller soundstages without Center Spread, but I hear no real differences whatsoever with the center spread feature on or off. If it's shrinking, it's probably due to the interaction of those compromised designs with the mains.

You could get some different room boundary effects, of course, which could change the sound mix in the room since the radiation/reflection patterns are changed, but with some early side wall absorption, this is largely reduced (I use tapestries on both sides to absorb a good bit of the first reflection while still looking snappy).

I also prefer to have active sources (front wides are close to the first reflection points so you get recording space based reflections instead of your own room, which let's face it, sucks compared to say Carnegie Hall). The more speaker simulated reflections from the recording and fewer room based ones the better for recreating the spaces on the recordings instead of a small room.

But that's just my opinion. People can do whatever floats their boats. God knows my overall room would be be very different if I had money to burn to build from scratch and I'd probably be using Storm equipment instead of Scatmos, but then maybe I'd miss some of the more interesting discoveries I've found along the way like Logic 7 mixed with Neural Surround over 15 speakers.

 

[laetoli37]

In other words, Center Spread is doing exactly the opposite of the purpose of the center, making it less stable and this is mostly to favor better sounding speakers because "most" home theaters apart from sound bars use different mains from the center

Used to mount my MTM center speaker beneath my projector screen - way below ear level . DSU upmixing just didn’t sound good. Center spread “helped” a bit , but still inferior compared to plain stereo listening. So I never bothered with DSU upmixing of stereo music.

When I changed to acoustic transparent screen, I was able to mount a new center speaker with good horizontal dispersion and at the right height. DSU upmixing of stereo is now highly satisfactory and my default setting. And I don’t need to turn on center spread!

 

[Chromatischism]

Yes and Center Spread is actually working against that stability by mixing the center speaker contents back into the L/R mains, largely defeating the entire point of a center speaker, which is to stabilize the center for off-axis seating.

But let's be real. Center Spread sounds better for up-mixed music, and some other types of audio, because it sounds bigger and more impressive. And we're using that mode mostly by ourselves in a central seat. But even if you have company, I could still argue for it.

I have identical front 3 speakers and Center Spread sounds better on than off. DSU puts too much to the center and audio loses its immersiveness.

 

[Magnus]

But let's be real. Center Spread sounds better for up-mixed music, and some other types of audio, because it sounds bigger and more impressive. And we're using that mode mostly by ourselves in a central seat. But even if you have company, I could still argue for it.

I have identical front 3 speakers and Center Spread sounds better on than off. DSU puts too much to the center and audio loses its immersiveness.

You missed my point, I think. All center spread does is NOT remove the center content from the Left/Right main speakers. So you end up with the center channel playing duplicated signals. It's no longer discrete and comb filtering doubles as well.

I recommend to just turn the center off entirely if Center Spread sounds "better" to you. It will sound even better yet. With 3 identical speakers mounted correctly in relation to one another, all Center Spread does is increase comb filtering. It may not be audible (I've found comb filtering claims of ruining sound overblown, personally), but it shouldn't be affecting, let alone improving stereo imaging over not using the setting with identical speakers.

The entire point of a center channel is to improve off-axis response for people not sitting in the center and that experience is better without signal duplication as that will pull the image off center once again, maybe less than no center, but not as well as a discrete center.

I suppose if you had your mains 80 feet apart or something, a center might fill the imaging gap from too large a distance between adjacent speakers compared to stereo, but that's not typical in a home situation. Generally speaking, you're probably better off without the center if you're at the MLP and certainly better off not using Center Spread (stereo only for non-matching or misaligned centers and normal without center spread for matching identical aligned speakers).

Of course you can do anything you want. I just think the correct reasoning should be mentioned less people think Center Spread is doing something magical. It's just like using a mixer to create a center instead of having it discrete.

 

[Chromatischism]

I don't believe that DSU merging certain sounds to a center speaker algorithmically is the same as adding a center speaker, or is the inverse of your AVR mixing center content to L/R speakers. It may be trying to do that, but there was an outcry from Denon owners when they disabled the feature, only to bring it back later because people preferred it for their use cases.

 

[Magnus]

I don't believe that DSU merging certain sounds to a center speaker algorithmically is the same as adding a center speaker, or is the inverse of your AVR mixing center content to L/R speakers. It may be trying to do that, but there was an outcry from Denon owners when they disabled the feature, only to bring it back later because people preferred it for their use cases.

All "music modes" even Logic 7's Music Logic and PLII Music said explicitly in the instructions that the music mode simply didn't remove the center channel information from the Left/Right mains. This gives a better image when using "center channel speakers" which are traditionally and usually inferior to the left/right mains.

Of course there was an outcry. It seems "most" people are still using inferior center channel speakers, often placed near the floor (to fit larger screens). You don't think those will harm imaging compared to the left and right towers or bookshelves? Of course they will. If they were better than the mains, you'd be using three center channel speakers instead!

Bringing the mode back doesn't mean it's needed with three identical, evenly placed speakers. It means too many people are still using compromised center channel speakers and complained. I told people back then to just turn off the center, but they didn't listen as they were convinced like that voodoo was involved or something.

Typical Center Channel speakers are OK for fixed dialog, but not the same as a primary main speaker.

I think they should have just put in a simple instant center channel toggle button on the remote to toggle off the center channel when playing music or watching by yourself. It's a pain to go into the menu system just for that.

 

[ernestcarl]

I think they should have just put in a simple instant center channel toggle button on the remote to toggle off the center channel when playing music or watching by yourself. It's a pain to go into the menu system just for that.

How about the option to significantly lower the center volume besides a mute toggle preset which is what I already do: https://www.audiosciencereview.com/...ds/omnidirectional-speakers.1283/post-1887678

 

[Magnus]

How about the option to significantly lower the center volume besides a mute toggle preset which is what I already do: https://www.audiosciencereview.com/...ds/omnidirectional-speakers.1283/post-1887678

I just don't see the point. If you're sitting in the center, you don't need a center channel and if you're sitting off center, a discrete center works better for that seat. I suppose center spread is the best option for a poorer center speaker and someone sitting off center as you will get at least partial benefit, but maybe not enough. It depends on the room and speakers.

 

[Chromatischism]

Of course there was an outcry. It seems "most" people are still using inferior center channel speakers,

Actually the outcry was from users who felt the center was getting too much isolated content.

How about the option to significantly lower the center volume besides a mute toggle preset which is what I already do: https://www.audiosciencereview.com/...ds/omnidirectional-speakers.1283/post-1887678

That is precisely what I do. Lowering the output of the center channel AND using Center Spread has achieved the best blend for me. Because contrary to how it's being depicted here, Center Spread doesn't just tell the mixer to not use the center. It blends the LF and RF speakers in but keeps the center blaring away with an algorithmically-steered mix.

 

[ernestcarl]

I just don't see the point. If you're sitting in the center, you don't need a center channel and if you're sitting off center, a discrete center works better for that seat. I suppose center spread is the best option for a poorer center speaker and someone sitting off center as you will get at least partial benefit, but maybe not enough. It depends on the room and speakers.

Actually. I have not found disabling the center consistently, every single time to produce a better effect or sound quality. I don’t share in your assumption that the center channel speaker I use and placement is all that inferior to that of my mains LR.

 

[Magnus]

Actually the outcry was from users who felt the center was getting too much isolated content.

There was an outcry because it was removed. Nothing was changed about its behavior when it was restored that I'm aware of. However....

That is precisely what I do. Lowering the output of the center channel AND using Center Spread has achieved the best blend for me. Because contrary to how it's being depicted here, Center Spread doesn't just tell the mixer to not use the center. It blends the LF and RF speakers in but keeps the center blaring away with an algorithmically-steered mix.

If the level isn't lowered by the mode, you would get ~3dB louder output towards the center, which would make it center heavy.

That's because while there's no bleed of non-center content into the center, it's sending the mains the full stereo signal without the center being removed from them. Thus, you get a duplicate center or 3dB higher output, but I assume the center spread mode decreased it automatically as I don't hear a louder center with it turned on.

I did have to get my center speaker perfectly aligned for it to sound exactly the same, however. Any small difference can lead to a preference one direction or the other.

Actually. I have not found disabling the center consistently, every single time to produce a better effect or sound quality. I don’t share in your assumption that the center channel speaker I use and placement is all that inferior to that of my mains LR.

But it's not identical so you will have a difference and that's the point. I said the mode isn't needed for three identical and properly placed speakers.

You can have a preference for any difference you might hear. It's hard to predict how two non-identical speakers will interact playing the same content. You might get a pleasing change in a given frequency range or something.

 

[ernestcarl]

You can have a preference for any difference you might hear. It's hard to predict how two non-identical speakers will interact playing the same content. You might get a pleasing change in a given frequency range or something.

That part is obvious. But there also are huge differences in media recordings — you already acknowledge individual preferences and differences in speaker-room system setups.

I do get your overall point, BTW. Yet I don’t agree with how you paint a broad brush that the center speaker must be inferior or the setup is suboptimal, and setups with exact identical speakers makes center mixing altogether irrelevant or useless.

 

[Magnus]

That part is obvious. But there also are huge differences in media recordings — you already acknowledge individual preferences and differences in speaker-room system setups.

I do get your overall point, BTW. Yet I don’t agree with how you paint a broad brush that the center speaker must be inferior or the setup is suboptimal, and setups with exact identical speakers makes center mixing altogether irrelevant or useless.

I'm just stating rational logic and known facts. You can believe whatever emotionally based reactional response type things you want.

The fact is center spread is less accurate with identical speakers as it produces more distortion (comb filtering) and I cannot think of anything beneficial whatsoever. What possible benefit could you get from duplicating the center information in the mains instead of playing it discretely? That produces comb filtering, if nothing else and while it may or may not be noticeable, what's actually better about it?

With less than identical speakers (yes that means inferior centers or you'd be using three centers not two other speakers) the effect is subjective at best.

If you prefer the L/R mains over the center (you must or you'd be using the center design for all three), it's not very logical sounding to prefer the comb filtering mess of L/R mains playing the center information over using no center at all, particularly when the mains are better speakers, but hey some people actually like Bose speakers, so I guess anything's possible.

I'd prefer this not to degrade into an emotional response kind of thing so I'm going to drop out the discussion of it.

It's just funny I got responses on my center spread comments and nothing else on upmixers or expanding one's setup cheaper than buying brand new AVRs (the high channel models aren't very good value per channel thus far).

There are some great deals on eBay for older Lexicon units and the Marantz 8015 is on sale at the moment as it's being replaced by the Cinema30. The 8015 may be the last model to support 7.1 inputs, which allow one to easily add Pro Logic IIx or Logic 7 capable processors without giving up Atmos/X/Auro. The European version even has Sony 360 support (MPEG-H).

 

[ernestcarl]

You can believe whatever emotionally based reactional response type things you want.

Eh, what?

I'd prefer this not to degrade into an emotional response kind of thing so I'm going to drop out the discussion of it.

Nobody here is censoring you.

The fact is center spread is less accurate with identical speakers as it produces more distortion (comb filtering) and I cannot think of anything beneficial whatsoever. What possible benefit could you get from duplicating the center information in the mains instead of playing it discretely? That produces comb filtering, if nothing else and while it may or may not be noticeable, what's actually better about it?

With less than identical speakers (yes that means inferior centers or you'd be using three centers not two other speakers) the effect is subjective at best.

If you prefer the L/R mains over the center (you must or you'd be using the center design for all three), it's not very logical sounding to prefer the comb filtering mess of L/R mains playing the center information over using no center at all, particularly when the mains are better speakers, but hey some people actually like Bose speakers, so I guess anything's possible.

I don't use "center spread" mode. I don't use an AVR or external processor. I use JRiver (cheap) with apparent mixing similarities to what it does -- but modified where the center is significantly reduced in level. It's easy to AB between different media content and DSP settings to determine what sounds better to my ears.


-------------

JRiver's JRSS pseudo-surround processing seems to be not really all that complicated -- at least from my simplistic mono signal testing:

Pseudo-Surround (ps) mode default results upmixing stereo LR to 5.1

L to ps BM CTR -7.5 dB
R to ps BM CTR -7.5 dB
L to ps SL -4 dB (delayed 20 ms)
R to ps SL -8 dB (delayed 20 ms) inverted
R to ps SR -4 dB (delayed 20 ms)
L to ps SR -8 dB (delayed 20 ms) inverted

While the levels and delays (30 ms rear channels) in 7.1c mode are different, it yields similar results in principle.