Dolby Pro Logic II vs. Stereo

[yoda313]

I assume it converts the audio to AC3 on the fly? I'm pretty sure the ffdshow audio decoder can do the same. Not that I've tried it myself.... only having 2 speakers and an inability to understand why the majority of the world thinks surround sound is such a wonderful thing.

Most likely.

And regarding ffdshow I'm assuming that is the case. However even though my pc is in my movie watching room I don't like watching movies on it. I feel its way overkill as far as power consumption and using remotes on a computer just doesn't do it for me - partly because I never really found a satisfactory combo that worked well.

Thats why I like the ouya or the wdtv or other settop units. Smaller form factor and all plus probably more energy efficient, not that I'm nuts on that subject.

half of them will swear black and blue every MP3 audio file ever encoded sounds like crap while

Well like everything how you encode it and what source you use makes all the difference. Personally to me a 320kpbs mp3 ripped from the original audio cd sounds nearly transparent or at least "rich" enough for my enjoyment. And the trade off between space and compatibility works. Even though I now use a 4" micro internet tablet as my mp3 player that will surely play flac or uncompressed wavs I want to have the convenience of compressed files so I can maximize a 32gb sd card without sacrificing too much audio quality.

as I don't like surround sound. I'd offer my spiel on how I find surround sound annoying but my spiel occasionally has the same effect on posters that surround sound does on me.

I think for me the two main benefits of surround are:

Discrete center channel for dialog

Discrete lfe for the subwoofer

As much as I like having the sound travel from front to back or all around the discrete center and bass are the real bonus.

Being able to hear dialog clearly over the music and effects tracks is a definite bonus. Plus the richness of a clean independent bass channel is all the more worth it for action movies and scifi/fantasy flicks. Nothing like it when you can rock out on big explosions - or better still concerts in surround sound

Theres one answer for you

[hello_hello]

A discrete bass channel I understand, although given our ears/brain are unable to distinguish the direction from which low frequencies originate (hence a single sub speaker being fine) I'd be unwilling to include the sub under a surround sound label, which means it therefore can't negate my argument.

Does having a centre channel make a fair bit of difference to the clarity of speech? I can't say I'd thought about it until now. Nor whether a centre speaker qualifies as part of the "surround" sound either, given it doesn't. Isn't it effectively an extension of the front stereo channels.... where the sound belongs.... sharing some of the workload so to speak.... while not actually being all "surroundy" about it.

Sound travelling from back to front... I honestly find it distracting and having the sound surround me seems to be more of a reminder that the picture doesn't than anything else, which is probably why it annoys me if I think about it. Oh well... each to their own.

[yoda313]

Does having a centre channel make a fair bit of difference to the clarity of speech? I can't say I'd thought about it until now.

I guess since I've had surround sound for so long I can't think about it without it. But personally it just makes it stand out more. Sound effects and "ambient" noises are separated more so that the dialog can carrry on its own more naturally.

I'd be unwilling to include the sub under a surround sound label, which means it therefore can't negate my argument.

But you can't really separate can you? Its the .1 in 5.1 after all. And its nondirectional yes but its part and parcel to the whole home theater experience for me personally.

Action movies just lack that literal punch if you don't have a sub channel and sub.

Sound travelling from back to front... I honestly find it distracting and having the sound surround me seems to be more of a reminder that the picture doesn't than anything else, which is probably why it annoys me if I think about it. Oh well... each to their own.

Well ideally in a movie it doesn't happen all the time.

In some commentary or featurrette I've watched they've talked about trying to make sure a movie isn't assaulting you all the time. It wears you out.


And in truth its not constant. Even in the big blockbuster movies you don't here stuff out of the rear channels every minute and second of the movie. Its really for ambience and special events.

[hello_hello]

I'd be unwilling to include the sub under a surround sound label, which means it therefore can't negate my argument.

But you can't really separate can you? Its the .1 in 5.1 after all. And its nondirectional yes but its part and parcel to the whole home theater experience for me personally.

I gave it serious thought and came to the conclusion the .1 in 5.1 can't be included under the surround sound label ....unless a sub in a 5.1ch system somehow surrounds you with sound in a way the same sub in a 2.1ch system can't.
Plus the way I understand it the discreet sub channel doesn't contain any sub frequencies which aren't already present in the two front stereo speakers... it just provides a boost to those sub frequencies, hence when downmixing 5.1ch audio to stereo, including the sub channel is optional (and according to Dolby is officially not included).
Okay maybe it also sometimes provides a boost to sub frequencies in the surround speakers, but I'm pretty sure the whole non-directional argument still applies.

Sound travelling from back to front... I honestly find it distracting and having the sound surround me seems to be more of a reminder that the picture doesn't than anything else, which is probably why it annoys me if I think about it. Oh well... each to their own.

And in truth its not constant. Even in the big blockbuster movies you don't here stuff out of the rear channels every minute and second of the movie. Its really for ambience and special events.

Maybe that's the problem. My brain's long been accustomed to taking in a 2D picture with stereo audio and converting it into something it can pretend is real, or however it works.... then 15 minutes into a movie a car door slams behind me or there's an explosion over my shoulder and my brain's reality router switches the incoming data to neural pathways created specifically for deciding if the noise was nothing to worry about or whether the microwave in the kitchen exploded, or for calculating the number of likely real world scenarios where a gun could be fired to my right without there being someone to my right to fire it... and it seems those neural pathways have to finish processing data completely before the neural pathways for suspending reality can take over again... or however it works.

[yoda313]

Maybe that's the problem. My brain's long been accustomed to taking in a 2D picture with stereo audio and converting it into something it can pretend is real, or however it works.... then 15 minutes into a movie a car door slams behind me or there's an explosion over my shoulder and my brain's reality router switches the incoming data to neural pathways created specifically for deciding if the noise was nothing to worry about or whether the microwave in the kitchen exploded, or for calculating the number of likely real world scenarios where a gun could be fired to my right without there being someone to my right to fire it... and it seems those neural pathways have to finish processing data completely before the neural pathways for suspending reality can take over again... or however it works.

Holy over-analyzing batman!

Wow.......

But yeah if you've only experienced a stereo world in the home environment I suppose that would make a "3d" sound world seem alien.

Speaking of which are you anti-3dtv then?

[hello_hello]

No, I'm not anti 3D. I own a 3D TV. My issue there is most 3D movies are crap.... I assume they're mainly shot in 2D and converted to 3D. Video shot in 3D can look great. The glasses get a bit tiring though. I wouldn't be wanting to use them too regularly. So no, I'm not anti, but I'm not a huge 3D fan either.

I got your PM. Thanks for that. Currently my PC is my media player and it's connected to some 2.1ch THX approved PC speakers so I never use the speakers in the TV. They're not the greatest sounding speakers in the world but they're quite good. Actually they're not 2.1ch now I think about it, just stereo with a sub with an active xover, but the sub still kicks out a decent amount of volume.

[yoda313]

No, I'm not anti 3D. I own a 3D TV. My issue there is most 3D movies are crap.... I assume they're mainly shot in 2D and converted to 3D. Video shot in 3D can look great. The glasses get a bit tiring though. I wouldn't be wanting to use them too regularly. So no, I'm not anti, but I'm not a huge 3D fan either.

Who'd a guessed? I was thinking you were against all "gimmicks" but apparently not.

I got your PM. Thanks for that. Currently my PC is my media player and it's connected to some 2.1ch THX approved PC speakers so I never use the speakers in the TV. They're not the greatest sounding speakers in the world but they're quite good. Actually they're not 2.1ch now I think about it, just stereo with a sub with an active xover, but the sub still kicks out a decent amount of volume.

Well just because something is "certified" doesn't mean they're top notch.

I just thought I'd mention the soundbar (pm) as an option. I was pleased there actually are 3.1 soundbars. That way you can reduce clutter but still get good front imaging that way.

[formalist]

There is no such thing as Dolby Pro Logic or Dolby Pro Logic II encoding.

Then what is this?


[Attachment 41856 - Click to enlarge]

Dolby Surround and Pro Logic II Encoder DP563:
https://www.dolby.com/us/en/professional/broadcast/products/dp563.html

(sorry, I know it's an old thread, but...)

[OneOcean]

More channels isn't necessarily better. If the source was stereo adding fake rear channels doesn't improve it.

There is nothing fake about the rear and center channels separated by Pro Logic II Music. The center channel is exactly what the artists intended to be placed in the front center of the sound stage. This center channel audio is better-anchored to the center of the sound stage for all listener locations in the room, unlike with the "fake" phantom-center effect created by stereo speakers.

The right-rear and left-rear channels contain only what the artist panned strongly to the right and left respectively. Depending on user settings, speaker locations, audio mix, etc... the rear channels can go from simply widening & separating the left and right audio, which is often needed when the front L & R speakers are located too close together on either side of a TV, to creating more discrete surround channel audio that can sound like the artist intentionally made the 5.1 mix. In fact, the Pro Logic II Music mix is much closer to what the artist originally intended than the discrete 5.1 mixes created by others years later.

I believe that Pro Logic II Music listening is better and closer to the artist's vision than listening with headphones, which is a pure 2D listening experience. PL II Music provides some of the fun of extreme stereo separation that headphones provide along with the important front-focused sound stage of stereo speakers. It is a very 3D listening experience that combines the the best features of stereo speakers and headphone listening without compromises.

All this said, the best PL II Music listening experience requires well-matched speakers located and configured correctly for the room and listener locations. Ideally, the five main speakers are all the same with the matching of the front three being the most critical. A lower-quality or poorly-matched front-center speaker may in fact make PL II listening less appealing than just with just a pair of good stereo speakers. I suspect much of the negative comments regarding PL II are from people who do not have a well-matched good-quality speaker system properly set up for 5+ channel listening. The rewards of PL II Music are there for those who have put together a proper system. This has been and continues to be a small percentage of listeners. Now with Dolby Atmos, which is even more equipment-critical, and the popularity of TV soundbars amongst the masses, the joys of the PL II Music experience will continue to be underappreciated.

[jagabo]

More channels isn't necessarily better. If the source was stereo adding fake rear channels doesn't improve it.

There is nothing fake about the rear and center channels separated by Pro Logic II Music.

Old movie releases often start with a mono or stereo soundtrack and add fake surround channels because the original sound recordings no longer exist. This is just so they can put "Dolby..." on the box to suck people in.