SM2 vs SPECWeb vs PENTEO 16 Pro

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I actually prefer a 4.0 Up-mix; I felt the Penteo spread the sound field too thinly in the fronts with a center channel, with less detail. Just to be clear though, the SpecWeb up-mixes I've heard have for the most part been very good. Hopefully there are various tweaks we can do in Penteo to improve it to our preferences. I'd bet it wasn't the Eagles quality of recording, just some weird glitch.
 
Well my screw up sort of got Glenn's (zeerround's) attention and he gave me a preview of SPECWeb 2.0, and the results from his yet-to-be-completed work. (He was kind enough not to yell at me! :) ) So in the spirit of equality, here is the same 30 seconds or so from ALL 3 OPTIONS, all with all 6 channels intact so you can judge for yourself. Again, all are defaults, even the SPECWeb 2.0, as Glenn did that one himself on the fly.

These are 24/44 5.1 .wav files

https://www.quadraphonicquad.com/Samples/01B-SPECWEB2-51.wav
https://www.quadraphonicquad.com/Samples/02B-PENTEO-51.wav
https://www.quadraphonicquad.com/Samples/03B-SM2-51.wav
 
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This idea sounds interesting. I need to read up on this subject. Any pointers very much appreciated.

Thank you for the reply & interest. The long answer can be found here:
https://www.quadraphonicquad.com/forums/index.php?threads/stereo-pre-synthesis.25299/
It has occurred to me that even the casual use of saying "out of phase blending" might need clarification. And indeed phase shift & polarity inversion is usually misused, myself included. Phase shift is a time sensitive context. To phase shift a 60Hz sine wave minus 90 deg relative to reference requires more delay in time than shifting a 6 kHz signal. Polarity is more straight forward as two waveforms are either matching in polarity or opposite polarity. Think of mismatching the hot/ground wire between two speakers. We would commonly call that out of phase but really it's opposite polarity.

So the classic Sansui way of creating their stereo synthesis mode was to take the left input, invert the polarity, reduce the level by ~ -7dB & mix it with the right input ch. At the same time the right input ch is inverted, reduced ~ -7dB & mixed with the left ch. Sounds complex at first but hardware it only requires one transistor & a resistor. It can be done in software as well.

Mixing the stereo input chs this way does a few things when decoded in classic Sansui gear or the SM.

1. It widens the front soundstage. This can be quite helpful in both studio music & live music where it makes a live performance more expansive.

2. It will send more direct sounds to the rear speakers creating a wrap around effect.

3. It will increase the sense of depth front to back.


If over used it will also noticeably reduce common mode signal such as bass or center front vocalist. It is easy to fine tune bass via software EQ & frequently that is useful anyway. You can always use the dreaded front ch in a not so dreaded way to raise the vocalist as desired.


The Adobe Audition has a tool I mentioned in the other post that dynamically varies the out expand effect. If there is no strong left right the expand is set to neutral. If there is strong left/right separation it will increase the opposite polarity mixing to the max you have selected. As far as I know this feature only exists in AA. It's been years since I've used Sound Forge so I don't remember what tools it has for this. Probably Jon could answer that.... look for an FX possibly labeled wide stereo field or the such. I just checked on Audacity & much to my surprise there is no stereo width control plug in I can find. I expect a quick google will find some freebie plug ins that at least do the simple opposite phase blending.


The cool thing about this is you can optimize surround sound decoding for an album, an individual song, or even change the values with in a song. Fun Stuff!
 
On the second set of samples (just on my computer):

The Specweb had a good sound overall but very loud and bass heavy (maybe a little too much bass) compared to the others.

The SMv2 sounded a little fuzzy on places on this one?

The Penteo sample has a more center channel sound to it which makes me think you were using the Discrete Mode (but looks like levels are easily adjusted?)
I personally like the Default Mode if you're not converting to 4.0 ;)
I don't believe I've heard the Composite Mode yet.

I'll check them out on my main system later, after my neighbor stops his leaf blower :mad:

Here's the different settings per the Penteo manual.

3 Penteo Center Channel Modes ā€“ Penteo provides three different modes for how sound energy is processed to the center
channel:

Default (formerly ā€œPenteo Musicā€) ā€ A good general purpose setting for the center channel where the discrete energy partly replaces
the phantom center provided at the input.

Discrete (formerly ā€œHard Centerā€) ā€ creates a totally discrete center channel. Ideal when the level or position of the mono content
may need later adjustment. Phantom center is completely eliminated with the faders at zero. If the C Fader is
pushed beyond 0dB, slight antiā€phase phantom center is added for a narrowing effect (use with caution). Backing off to
a negative setting puts back some of the original phantom center.

Composite (formerly ā€œStereo+ā€) ā€ A more subtle center energy setting where front L and R outputs differ from the input in level
only. Particularly suitable for ā€œset and forgetā€ use or when surround channels might be lost further down the processing
chain. In this mode, the C fader is crossā€linked to the Lssā€Rss fader.
 
Well my screw up sort of got Glenn's (zeerround's) attention and he gave me a preview of SPECWeb 2.0, and the results from his yet-to-be-completed work. (He was kind enough not to yell at me! :) ) So in the spirit of equality, here is the same 30 seconds or so from ALL 3 OPTIONS, all with all 6 channels intact so you can judge for yourself. Again, all are defaults, even the SPECWeb 2.0, as Glenn did that one himself on the fly.

These are 24/44 5.1 .wav files

https://www.quadraphonicquad.com/Samples/01B-SPECWEB2-51.wav
https://www.quadraphonicquad.com/Samples/02B-PENTEO-51.wav
https://www.quadraphonicquad.com/Samples/03B-SM2-51.wav

The SpecWeb sample is so different from the sample you provided yesterday Jon...in a good way. Now it is very difficult to choose between these new samples. I can see why you were surprised and annoyed about the results yesterday, as they didn't do any justice to the SpecWeb's handling of it's upmix capabilities.

Now that really does set the cat amongst the pigeons.

Perhaps more samples are required, for us discerning listeners, to get a true appreciation as to which upmixer has the final say in it's ability.
Or maybe it's too close to call.
 
Of course many things will come down to settings (like bass/amount of LFE) but re "loud" there has been a ton of work to make the loudness of SpecWeb output come out the same as the loudness of the original stereo track. It is normally within 0.5 dB, for SpecWeb 2.0 Beta 1.

"Loudness" is according to the EBU R128.

It's worth noting however, that the EBU R128 Spec doesn't take LFE into account so feedback on the LFE level in SpecWeb is appreciated. However there's also the whole +10dB yes or no in bass management discussion... but in general the LFE in SpecWeb should be 9dB or 13 dB down from everything else (I need to check the code) with your bass management crossing over the other 5 channels and feeding it to your subwoofer (along with LFE).
 
More results:

Well, I have to admit that while both SPECWeb 20 and Penteo 16 Pro do an incredible job with appropriate material (some songs just do not work), when they work it is VERY HARD TO TELL which program does a better job. When you consider the cost of being able to use PENTEO, I am not sure that it's worth the price or the attached strings (iLok, Reaper).

Listen to these two samples. These are 24/96, sourced from an HDTracks file (that I paid for by the way)
It's the first 40 seconds or so of Carly Simon "You Belong To Me". These are all defaults. It came out really good.
The differences in the wav forms is glaring, but the audio is really close.

Which one sounds better to you?

https://www.quadraphonicquad.com/Samples/TEST-YB2M-SPEC.wav
https://www.quadraphonicquad.com/Samples/TEST-YB2M-PENT.wav

YB2M.jpg
 
More results:

Well, I have to admit that while both SPECWeb 20 and Penteo 16 Pro do an incredible job with appropriate material (some songs just do not work), when they work it is VERY HARD TO TELL which program does a better job. When you consider the cost of being able to use PENTEO, I am not sure that it's worth the price or the attached strings (iLok, Reaper).

Listen to these two samples. These are 24/96, sourced from an HDTracks file (that I paid for by the way)
It's the first 40 seconds or so of Carly Simon "You Belong To Me". These are all defaults. It came out really good.
The differences in the wav forms is glaring, but the audio is really close.

Which one sounds better to you?

https://www.quadraphonicquad.com/Samples/TEST-YB2M-SPEC.wav
https://www.quadraphonicquad.com/Samples/TEST-YB2M-PENT.wav

View attachment 44345
To my ears Jon, the penteo upmix slightly has the edge in terms of clarity but there is so little in it, that, as you said, the extra cost of the penteo just doesn't seem to be worth it.
I just need to get my act together and give specweb a proper try.
This is the kick up the rear I need, now I've heard these results.
 
On first listen they both sound good to me, but on this song, I definitely like the SpecWeb better, seems more detailed, especially the bass.
Nice song too!
There must be certain fine adjustments within the programs (that I don't know about yet) to manipulate to our tastes? But I'm looking for plug 'n play easy, as I've got hundreds, maybe thousands of songs I'd like to convert.
 
Me too! I am going nuts trying to figure out which one is better. The Penteo seems "smoother", but the SPEC seem more defined, but they are SO CLOSE that when I listen to one, I say "That's it. The better", until I listen again to the other, then I decide that one is better.

IT'S INCREDIBLY CLOSE.

That being said, you have to marvel at what Glenn has done with SPEC since its inception. The guy is a genius. a true wizard.
A Surround Wizard.
 
it is amplitude based decoding only.

FYI that is not totally accurate for modern versions of SpecWeb, and the Immersive version in the works.

SpecWeb has "ambiance extraction" options (but off by default, depending on the version anyway), which can place de-coherent sound in the virtual rear center, and in my immersive work for upmixing stereo to 7.1.4 (11.1 if you prefer) de-coherent sound is routed to the the height speakers.
 
I hear swishy artifacts on the vocals of the specweb 20 version. Maybe that's because of the increased amount of detail or louder volume of that sample. The penteo is smoother without the swishy vocals or increased detail. Maybe you could blend the fronts of the penteo with the rears of the specweb 20 and balance out the volume for the best of both methods version. But as they are, I prefer the penteo. Thanks for the opportunity to listen to both methods side by side.
 
FYI that is not totally accurate for modern versions of SpecWeb, and the Immersive version in the works.

SpecWeb has "ambiance extraction" options (but off by default, depending on the version anyway), which can place de-coherent sound in the virtual rear center, and in my immersive work for upmixing stereo to 7.1.4 (11.1 if you prefer) de-coherent sound is routed to the the height speakers.
Thanks for the info & update. Can you tell me which versions of SpecWeb has ambience extraction? Or how to turn it on in the latest version?
 
From the ini file in the 2.0 b1 version (which I just noticed makes shortcuts that say 2.0a2 :oops:)

[ambiance]
;Ambiance extraction works with ArcTan (or ArcTan + Slice)
;it routes "ambient" or "decoherent sound" around ArcTan to a virtual center rear channel
;Besides adjusting the "Amb Extraction" control in the Web Playback interface,
;you can use the "Flipped Surround" setting in the monitor mode dropdown (Surround, Original Stereo,
;2x2 Stereo, Flipped Surround) to isolate the ambient signal in the C channel (which can then be solo'd, etc.)
;"Flipped Surround" puts the C channel in a virtual rear center, LF in LS, RF in RS, and the virtual rear center (ambient) signal
;in C.
;
;Ambiance extraction gives an added depth to the surround field, but DOES NOT add any signal (ambiance or other) that wasn't
;there in the original stereo. It simply pulls it out of the surround field and routes it to a virtual rear (1/2 the signal
;sent to each rear channel).
;
;0 = no ambiance extraction
;1 = full ambiance extraction
;0 to 1 default 0
crossfade=0
;
; OK by popular demand there is now an option to add, vs. crossfade, the decoherent signal to the virtual center rear. When you use this
;option you are adding additional sound to change the original mix. Instead of the decoherent sound being routed AROUND arctan it will be
;left in arctan AND be routed to the virtual center rears
;
; crossfade (default) = any extracted signal is crossfaded between arctan and virtual rear center
; add = any extracted signal is added to the virtual rear center and is left in arctan as well
ambientmode=crossfade

So one way to turn it on is by changing the ini file (The program looks for ini files in this order:

1) an ini file with a name that matches your song file name
2) a SpecWeb.ini file in the same directory as our song(s) file
3) the SpecWeb.ini file in the \install\bin directory

)

In that way you can have different ini settings for different songs or directories.

Then there are command line options (which override ini settings):

-ex = Set Ambiance Extraction Amount (0 to 1 default 0.0).
-gx = Set Ambient Extraction Mode. 0 = crossfade, 1 = add (default crossfade)

So using the SpecWeb icon on your desktop when it asks you "Enter Options or hit return to accept all defaults" you could enter, for example:

-e0.85 -g1
 
Just to let folks know.,,,.I've spent the past few days trying to get to grips with SpecWeb (novice to this type of programme) and more recently the new trial version of Dolby Atmos.
Eventually after much scratching of this old noggin, I got the 5.1 channels to play as advertised and have played the immersive trial version.
As I said to Glenn, the 7.1.4 sound is light years ahead of the 5.1 mix and I look forward to this being more widely available in the near future.
 
I am working on something right now that is not really up the general QQ Member's alley musically, but I am stunned at how much better the SPECWeb is doing compared to Penteo.

In a while I will post about this.
 
Well, this might not be an audio title that folks here are clamoring for, that's for sure. But today I was doing the broadway cast album of "The Producers". I am not a big broadway musical guy, far from it, but I am a big Mel Brooks fan, and loved the original movie. I took my wife to see the play when it was on Broadway and at the time thought is was great as was most of the music, which Mel Brooks wrote himself. So we ended up seeing this play a few times in other places and I got the CD way back when so I know it well.

Anyway, my wife asked why I didn't have this for the car, and of course I don't like to take stereo in the car, so today I decided to finally take a crack at it and I ran it through Penteo just to have something for the car. But when I listened to it on the PC, it was pretty much the same info in all of the main channels. Very mudane and boring. Nothing was highlighted or low lighted. The lead vocal was in all the channels, as well as all of the other vocals. It was pretty much wide stereo. Not impressed. (Remember though, I was using defauts and DEFAUT.

A few days ago, Glenn asked me to try a SPECWeb parameter to see how it worked. He told me to enter -m4 when the program window says "Press Enter to use the defaults", which is what I always have done.

So today, I decided to try -m4

What a difference! The SPECWeb pulled out the orchestra, the background vocals, the sound effects, and kept the lead in the center. Very wide distribution. And hardly any artifacts, if any. (Remember, my ears aren't what they used to be, no freq's over 11K)

Anyway, it's totally different with SPECWeb than the Penteo on this one. Here's a look at the same exact song done with both programs. You'll have to take my word on the sound, but you can CLEARLY see that SPECWeb pulled stuff out of the stereo and put it into separate channels where Penteo just spread things around.

One of the amazing things on this tune is that at the end, Nathan Lane and Matthew Broderick are singing at the same time, and somehow the SPECWeb pulls Matthew out of the center into the Front Right, so the duet at the end is very discrete.

I really was blown away by this and will try the -m4 on tunes more likely to be listened to by the QQ Hordes! :)

Here's a look at the Wav files. Guess which is which...........


PRODUCERS.jpg
 
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Well, this might not be an audio title that folks here are clamoring for, that's for sure. But today I was doing the broadway cast album of "The Producers". I am not a big broadway musical guy, far from it, but I am a big Mel Brooks fan, and loved the original movie. I took my wife to see the play when it was on Broadway and at the time thought is was great as was most of the music, which Mel Brooks wrote himself. So we ended up seeing this play a few times in other places and I got the CD way back when so I know it well.

Anyway, my wife asked why I didn't have this for the car, and of course I don't like to take stereo in the car, so today I decided to finally take a crack at it and I ran it through Penteo just to have something for the car. But when I listened to it on the PC, it was pretty much the same info in all of the main channels. Very mudane and boring. Nothing was highlighted or low lighted. The lead vocal was in all the channels, as well as all of the other vocals. It was pretty much wide stereo. Not impressed. (Remember though, I was using defauts and DEFAUT.

A few days ago, Glenn asked me to try a SPECWeb parameter to see how it worked. He told me to enter -m4 when the program window says "Press Enter to use the defaults", which is what I always have done.

So today, I decided to try -m4

What a difference! The SPECWeb pulled out the orchestra, the background vocals, the sound effects, and kept the lead in the center. Very wide distribution. And hardly any artifacts, if any. (Remember, my ears aren't what they used to be, no freq's over 11K)

Anyway, it's totally different with SPECWeb than the Penteo on this one. Here's a look at the same exact song done with both programs. You'll have to take my word on the sound, but you can CLEARLY see that SPECWeb pulled stuff out of the stereo and put it into separate channels where Penteo just spread things around.

One of the amazing things on this tune is that at the end, Nathan Lane and Matthew Broderick are singing at the same time, and somehow the SPECWeb pulls Matthew out of the center into the Front Right, so the duet at the end is very discrete.

I really was blown away by this and will try the -m4 on tunes more likely to be listened to by the QQ Hordes! :)

Here's a look at the Wav files. Guess which is which...........



PRODUCERS.jpg
Very promising indeed, the real test are these type of songs that donā€™t typically decode very discretely.
Iā€™m wondering if the -m4 is similar to AA3ā€™s Stereo Pre-Synth (just donā€™t ask me to explain it šŸ¤·ā€ā™‚ļø)
 
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