Dolby Surround (2014) vs Dolby Pro Logic II

[Wunlow]

There have been a few alternate matrix surround encoding methods for theatrical (which then goes to home video) or encoded to home video directly such as Ultra-Stereo for optical film soundtracks, or Shure's previous HTS Surround encoder for home video encoding. Both encoders were compatible with the core DPL-1 matrix. But agreed though: the overwhelming majority of matrix encoded films or TV shows have been done with official Dolby (DPL-1) encoders. Some direct to video or videogame 2-ch audio did or do utilize DPL-2 encoding.

I've done tests on the older Neo6 decoding and can confirm the matrix decoding steering did indeed change over various iterations but both were DPL-1 compatible and was verified with test tones. That being said, both of the Neo6 decoders I had tested did not properly decode my DPL-2 left surround and right surround pink noise tests. Center back (DPL-1) decoded fine.

I was able to test DTS's neural X decoding a few years back and can confirm it does properly decode DPL-1 and DPL-2.


Unfortunately I do not have access to the latest Dolby Surround decoder ("Dolby Surround" in this given case being the latest upmixer / decoder bundled with Dolby Atmos) and would be very surprised if the newer Dolby Surround decoder was not at least compliant with DPL-1. There have been wildly conflicting reports on the Dolby matrix decoding accuracy. Has anyone used actual test ID tracks to confirm that it is Dolby DPL-1 compliant? And for DPL-2 decoding have DPL-2 tests checks been tried vs using QS test tones? I can provide the needed audio checks to anyone interested.

 

[furui_suterioo]

Does DSU have any parameters or is it just digital mystery secret AI?

 

[Owen Smith]

I was able to test DTS's neural X decoding a few years back and can confirm it does properly decode DPL-1 and DPL-2.

I don't like DTS Neural X, I've tried it on a few types of material and it always puts far too much into the centre speaker for my liking. Auro 2D appears to do very little and is too subtle for TV, it might be OK with music.

Unfortunately I do not have access to the latest Dolby Surround decoder ("Dolby Surround" in this given case being the latest upmixer / decoder bundled with Dolby Atmos) and would be very surprised if the newer Dolby Surround decoder was not at least compliant with DPL-1.

I've settled on the new Dolby Surround as the one that least annoys me. But it steers too much into the rears I feel, DPL II was better to my ears. I never liked DPL, the mono rears drove me nuts.

There have been wildly conflicting reports on the Dolby matrix decoding accuracy. Has anyone used actual test ID tracks to confirm that it is Dolby DPL-1 compliant? And for DPL-2 decoding have DPL-2 tests checks been tried vs using QS test tones? I can provide the needed audio checks to anyone interested.

I don't have test tones. If you have some DPL I and DPL II test tones I am very interested in testing them on my Arcam AVR31, I can easily play FLACs.

 

[Owen Smith]

Does DSU have any parameters or is it just digital mystery secret AI?

It's all secret, typical of Dolby these days.

 

[MidiMagic]

I don't like DTS Neural X, I've tried it on a few types of material and it always puts far too much into the centre speaker for my liking. Auro 2D appears to do very little and is too subtle for TV, it might be OK with music.

I've settled on the new Dolby Surround as the one that least annoys me. But it steers too much into the rears I feel, DPL II was better to my ears. I never liked DPL, the mono rears drove me nuts.

I don't have test tones. If you have some DPL I and DPL II test tones I am very interested in testing them on my Arcam AVR31, I can easily play FLACs.

It is not a matter of how it steers content.

The question is, do the sounds come from the same direction on the new system that they are heard coming from with PL?

The "mono rears" have never been an issue to me. I listen for the direction the sound seems to come from. When playing the same DS recording, it should seem to come from the same direction with DS, PLI, or PLII decoders.

 

[jaybird100]

That is not quite what happens. There were no actual channels designed into the original Dolby Stereo/Surround encoding.
View attachment 98088
You just encoded the sound wherever you wanted it to appear around this encoding circle. I have such an encoder. It has a pan pot and a front/back switch for each mixer channel.

The decoder just used a different decoding angle on the same circle for a different speaker configuration.

The Original DS and PLI decoders used the angles L, R, F, and S.

The PLII decoder used the decode angles L, R, F, 3, and 4.





That is bad to know. They are obsoleting all of our old movies.

I do not want a stupid new downmixer or upmixer that does a bad job. I want my old movies to play the correct way. I also want all of my matrix records (QS, SQ, EV, DQ, DS) to play correctly.

I am not leaving the past behind. All of my recordings and movies are done with the old system. So I do not want Atmos or HDMI.

All the more reason to use a Surround Master!

 

[Owen Smith]

The "mono rears" have never been an issue to me. I listen for the direction the sound seems to come from. When playing the same DS recording, it should seem to come from the same direction with DS, PLI, or PLII decoders.

Not true. The mono and 7Khz cut on the rears in DPL is done in the decoder. Neither of those apply in a DPL II decoder so the same content can play back differently in DPL II rears.

 

[Owen Smith]

So does anyone have DPL or DPL II test tones I can try on the Dolby Surround (2014) decoder?

 

[ssully]

Does DSU have any parameters or is it just digital mystery secret AI?

DSU has only 1 user-adjustable parameter: Center Spread, allowing 'on' and 'off'.

IIRC, "On" equates to the DPLII Music Mode Center Width default value of 3 (center and L/R approximately balanced). "Off" is more center-focused , perhaps equating to "0", which I think was the old DPL II 'Movie mode' setting too (which could not be changed).

DPL II Music CW options ranged from 0 to 7 , with 7 being no center, aka phantom center

 

[ssully]

So does anyone have DPL or DPL II test tones I can try on the Dolby Surround (2014) decoder?

Doesn't this previously-posted disc have DPL I test tones?


https://delosmusic.com/recording/surround-spectacular-the-music-the-tests/

 

[Owen Smith]

Doesn't this previously-posted disc have DPL I test tones?

I don't have that disc, and ordering it from the US is unattractive given probable postage costs and import duty. I'm only looking for 30 seconds of channel ID FLAC here.

 

[ssully]

I don't have that disc, and ordering it from the US is unattractive given probable postage costs and import duty. I'm only looking for 30 seconds of channel ID FLAC here.

21 currently for sale on discogs from these countries:


Ships From
9 United States
3 Netherlands
2 Canada
2 United Kingdom
1 Australia
1 Belgium
1 Germany
1 Japan
1 Sweden

https://www.discogs.com/sell/release/2909101?ev=rb#more=ships_from

 

[Owen Smith]

Don't worry, I didn't look at the drop down box for format, delosmusic.com just sold me a FLAC copy for USD 7.98.

I should add I was not previously aware of the existence of this disc, so wherever it was previously posted I didn't see it.

 

[ssully]

In this very same thread, back in 2019

https://www.quadraphonicquad.com/fo...-2014-vs-dolby-pro-logic-ii.26126/post-419630

 

[Owen Smith]

In this very same thread, back in 2019

https://www.quadraphonicquad.com/fo...-2014-vs-dolby-pro-logic-ii.26126/post-419630

I probably wasn't reading this thread back then.

 

[Wunlow]

So does anyone have DPL or DPL II test tones I can try on the Dolby Surround (2014) decoder?

I'm currently at work but will work on getting you those here soon.

 

[fizzywiggs41]

There's also this cd.....

Chesky/Stereo Review CHE 151

 

[MidiMagic]

Thanks to some folks on another thread, I've belatedly discovered the Dolby Surround plug-in (I think it emulates PLII, but I may be mistaken) for foobar2000. I'm finding it's a good solution for playing my old Dolby Surround CDs. I understand MidiMagic is concerned about his film collection, however; not sure if there's a comparable plug-in for VLC Player.

My films are on DVDs with no computer in the audio system. So I need a REAL PL decoder.

Yoohoo receiver makers. If you don't offer real Dolby Pro Logic II as a selection, you have lost a customer.

 

[kfbkfb]

IMHO, the actions of Dolby Labs seem bizarre, there's probably more Dolby Surround matrix encoded content (mostly movies and TV shows) than content in any other matrix system yet there's no official new (in 2023) original Dolby Surround hardware decoder.

Maybe the A/V receiver makers could play the game some played in the early days of Dolby Surround - build in a no logic decoder that is close to a true original Dolby Surround decoder but call it a cinema surround decoder.

(I also play my VHS/CED/LD/VideoCD/DVD/HD-DVD/[UHD]Blu-ray movies with the appropriate player)


Kirk Bayne

 

[Marconi]

So does anyone have DPL or DPL II test tones I can try on the Dolby Surround (2014) decoder?

on you tube, look for National Kid who has built a QS encoder and has posted a lot of Encoded material including a set of test tones for all channels. On my Yamaha 1030 in DPL mode I get full QS compatibility. The you tube source may not be hifi but it is mostly listenable and the multi channel works very well. It means you can at least listen to music on an amp with no discrete multichannel inputs. I also have a Sony 3500 which does have discrete inputs and I have that set up with an Involve Audio SQ decoder development kit via the zone 2 output.