[Help] Dolby Surround 2.0 Matrixed files Upmix

[captainsolo]

Same here. I have to say at first I was weirded out by the stereo surrounds in PLII for older titles and then realized that when it doesn't try and stereoize it-the decoding is much more accurate. PLIIx in a 7.1 system does an even better job due to having the rear surrounds to play with.

[schorman]

I picked up an HTS 5300 this summer. Does anyone have something they'd like me to run through it? I'd like to see what kind of results I can get.

[spoRv]

I picked up an HTS 5300 this summer. Does anyone have something they'd like me to run through it? I'd like to see what kind of results I can get.

Do you know that I hate a lot, and probably I am not alone?!?

No idea right now, but I'm sure soon someone will find a film to be processed by it!

[captainsolo]

I want to find one of these things so badly.

[schorman]

I want to find one of these things so badly.

I understand, lol. I was shocked to find it actually. And it was only $47 shipped.

[captainsolo]

I want to find one of these things so badly.

I understand, lol. I was shocked to find it actually. And it was only $47 shipped.

Where did you find it? I've had an ebay search alert set for years.

[schorman]

ebay:

https://www.ebay.com/itm/SHURE-HTS-5300-...2749.l2649

Incidentally, I was wrong about the price. I'm pretty sure I paid for shipping.

[CSchmidlapp]

A quick question for you all relating to this.

At the final audio mixing stage of a film (pre-optical / digital sound release prints), would the sound engineer / director have mixed in a surround environment?
e.g Left, Centre, Right, Surround(s)
Then its encoded to 2 channel with the channel information 'matrixed' in only for delivery?

[deleted user]

A quick question for you all relating to this.

At the final audio mixing stage of a film (pre-optical / digital sound release prints), would the sound engineer / director have mixed in a surround environment?
e.g Left, Centre, Right, Surround(s)
Then its encoded to 2 channel with the channel information 'matrixed' in only for delivery?

I think they likely mixed in 4-channel and then ran it through a Dolby SEU4 (which outputs the matrixed 2 channels) and then back through a Dolby SDU4 (which gives you back the de-matrixed signal as 4 channels) in realtime to see whether it still sounded good and perhaps made some adjustments if it didn't. 

This is what I gather from the manuals and info I read on the Dolby SDU4.

The Dolby SEU4 and SDU4 are the reference encoders & decoders for studio use, all with symmetrical inputs and outputs.

[pipefan413]

Wait...there's a PL1 standard mode on newer PLII systems? How in the world do you access that?

The DPL-1 mode was originally part of the DPL-2 package, including at a minimum the DLP2 Movie and Music Mode. My last receiver (circa 2012?) still included all three decoding modes. 

That said, Dolby has done a recent shift in their decoding marketing.  Dolby Atmos receivers have a generic mode simply called "Dolby Surround" that replaces DPL-2, in that, along with Dolby Atmos upmixing of 7.1 and 5.1 discrete tracks, it also does updated decoding of Dolby Stereo soundtracks to 5.1, 7.1, or Atmos speaker configurations. Rear decoding still has split surrounds like DPL-2. From what I understand, the DPL-2 decoding matrix equations are still adhered to, only the logic processing has changed. With Dolby Atmos receivers & processors, DPL-2 decoding is now optional, as in the manufacturer has to pay a little extra to include DPL2 if they want that on board as well. And a few higher processors have done just that.

If a receiver or processor does not use Atmos processing, then DPL-2 is still the default.

I have not had a chance to test a Atmos Dolby Surround decoder, and would love to throw some torture test material at it someday.

I'm currently obsessing over this stuff because I suspected my AVR was not decoding older 4.0-to-2.0 matrixed mixes very accurately and unless I'm misunderstanding, this appears to confirm my fears. This is an old thread, so apologies if reviving it is a horrible idea, but it appears to be relevant to my current predicament and I don't see another that's more up to date.

My AVR is a Denon which has no Pro Logic IIx, II, or legacy Pro Logic mode, instead only including a "Dolby Surround" mode since it is indeed an Atmos receiver. I thought I was doing myself a favour for future-proofing purposes by getting one that could decode both Atmos and DTS:X at the time, but it seems I may actually have locked myself out of correct decoding of legacy Pro Logic. Thus far, I only have the ability to use rear surrounds for 7.1 rather than ceiling mounting any speakers for Atmos or whatever (rented accommodation and all that). Plus, I don't have any real desire to switch to 4K any time soon so I don't think I have any discs with Atmos or DTS:X anyway (though I do have several with 7.1).

Am I correct in thinking that the newest "Dolby Surround" (Atmos generation) mode is incapable of turning the mono surround channel from a 2.0 Dolby Stereo / Dolby Surround / Pro Logic track into a mono surround on the back speakers? Does it divide it into 2 (or possibly even 4, in a 7.1 setup) slightly different channels instead? I can't think of a clear way to test; I guess I'd need to think of an early stereo matrix encoded film that has easily distinguishable stuff in the mono surround channel to see if I can spot any difference in the middle and rear surround speakers. To be fair, I expect any difference is probably fairly minimal anyway if I have even roughly the right understanding of how the phase splitting works. But I'm all about the authenticity.