Dolby Surround processor better than computer program stereo-to-5.1

[clashradio]

I’m looking to capture the Dolby Surround track from laserdiscs & from what I’ve read, Pro Logic 2 splits up the channels the best (better than Pro Logic, Logic 7, Neo 6, Circle Surround Cinema etc), with Logic 7 being the next best.

This is for laserdisc preservation to output to dvd/BD and have the audio options of 2-channel PCM stereo and 5.1. Ultimately would like to make my own equivalent Dolby Digital mix from Dolby Surround. I’ve read the Atmos mode actually is the best with Dolby Surround but I don’t want an amplifier, only a processor. And it must be old enough to have pre-amp analog RCA outputs (L&R Front, Center, L&R Rear, Sub) and new enough for digital s/pdif inputs (rca coax and toslink). I know D.S. does not have a Sub channel.

Some processors I’ve been considering are:
-Lexicon DC-1 (or DC-2)
-Pioneer Elite SP-D99/SP-D07
-Meridian 561/565
-Marantz DP-870

I understand this mix won’t be as discrete as true Dolby Digital. Sources say Pro Logic 2 actually creates stereo Rear surrounds and seems to do well with the Center channel as far as dialog goes.

A 2001 online article from Stacey Spears mentions the Meridian 861 having Pro Logic 2, and the Lexicon DC-2 having Logic 7, but I can’t find any other unit that has Pro Logic 2, other than certain amplifiers.

Most of my LD’s are Dolby Surround. I have a few with Dolby Digital and already have a D.D. AC-3 RF processor.

Anyone have any experience with Dolby Surround processors?

Anyone know if the Meridian 565/562 has Pro Logic 2? Can I use the Meridian as a pre-amp? Or is the only output the digital-rca outputs that mate with Meridian digital speakers?

How well does the Lexicon DC1 or DC-2’s Logic 7 split the channels?

Or is there a computer program that does stereo-to-5.1 splitting as well as a physical unit?

[Cornucopia]

Haven't used an actual physical processor since 2001 (little DS "work" since then). There are quasi-"2sd-to-5.1" processing apps/scripts. Since they're almost all reverse engineered, they aren't quite as accurate as the real thing.

Not sure why you really need it pre-processed though, as almost ALL modern surround receivers and computer+amp combos support direct decode+de-matrix+surround playback. IIWY, I'd leave it as LPCM 2ch and just engage DS modes at the amp when applicable.
That way, there's no re-encoding or (lossy)compression losses.

Scott

[clashradio]

I want to capture the surround audio like a multi-track mix (if I end up using a processor). I want to have the two audio options on the BD menu. My soundcard is capable of multi-track captures. 2-track is a no brainer.

When I say "pre-amp" I mean I need the analog rca 5.1 outputs to not be powered; so I can run those into my soundcard.

I realize when most people hear Pro Logic/PL2 they think of their amplifier running speakers.

[Cornucopia]

Yeah, but all those people have amps/receivers where the DS decoding/dematrixing and/or "upmixing" is done in the preamp sectionof the amp.
All YOU need is an amp/receiver that also has multichannel analog out (and of course your multichannel capture card). Probably a good deal easier (and cheaper?) finding that that than those dedicated processors - especially since the bulk of the dsp cost in the processors is in the encoding, not the decoding (not necessarily re complexity, but more due to IP royalties on the "standard").

Wouldn't be my favorite way of authoring, but if that's what you want and you at least are keeping as an option the original LtRt track, should be doable.

Is your end-use amplifier HDMI- or multitrack analog- capable? Cuz if not, the multitrack is kind of wasted. SPDIF doesn't support multitrack options except when using AC3 or DTS passthrough, and both of those will incur the recompression quality loss penalty.

Scott

[clashradio]

Ya Scott, you may be on the something; my end-use amp only has s/pdif toslink (which I keep forgetting is only capable of 2-track).

Also, I didn't realize some amps have analog multi-channel out, as I though the amp is designed to have multi-channel in that accepts the signal(s) from the processor?

This goal of mine is basically for future-proof stuff, so when I do get a hdmi-ready amp.

Yes I would still have the PCM 2-channel as an option. Sony Vegas Pro 12 accepts 5.1 multi-channel audio so I think it would be neat to make a BD with both audio options.

So do you think I'm better off using some sort of computer stereo-to-5.1 program?

[Cornucopia]

Depends on what you mean by "better off". But certainly you wouldn't be paying for specialty hardware that you might only occasionaly use (in either of the mentioned scenarios above).
There are a number of upmixing plugins available, especially some pay ones used in DAWs like ProTools, but I would first start with free, opensource ones, like MatrixMixer, and work up from there. Test with a variety of sample types (voice/dialogue - male & female, pop/rock music, jazz, classical - rich & lean/solo, sfx, full movie soundtracks), and compare both stereo (LtRt) unprocessed, sotware-processed upmix, and hardware decode.
Check for imaging clarity, phantom stability (no position shifting or jumping), eq smoothness & richness/fullness, lack of phase-shifting, minimization of crosstalk, accuracy of expected placement...

Scott

[clashradio]

Better off meaning would a modern program do better with the matrix-separating than a vintage piece of equipment? would probably be cheaper. But like equipment I'm sure better programs to better decoding as you stated with ProTools.