Mono DVD Soundtracks

[Quagmire]

John,

You said...

"Yet I still dont understand the packaging or marketing behind this---if there are two channels of audio available to begin with, why not offer the DVD in "Dolby Stereo Surround" rather than have two channels of identical audio collapse into a one channel mono experience?"

This is at the very heart of the issue... there AREN'T two channels of audio available to begin with. The original soundtrack IS a mono track. In order to change it, a remaster would have to be done. It would be great if they remastered all such tracks to at least a Dolby Stereo Surround format as you say, but in many cases they don't. The point is that they are not downgrading a stereo track to a mono track for the DVD release, they are mearly keeping the original mono track intact.

Q

[John Beresford]

John,

You said...

"Yet I still dont understand the packaging or marketing behind this---if there are two channels of audio available to begin with, why not offer the DVD in "Dolby Stereo Surround" rather than have two channels of identical audio collapse into a one channel mono experience?"

This is at the very heart of the issue... there AREN'T two channels of audio available to begin with. The original soundtrack IS a mono track. In order to change it, a remaster would have to be done. It would be great if they remastered all such tracks to at least a Dolby Stereo Surround format as you say, but in many cases they don't. The point is that they are not downgrading a stereo track to a mono track for the DVD release, they are mearly keeping the original mono track intact.

Q

Q:

So then WHY the "2.0" designation if the "original soundtrack IS a mono track" as you say....what am I not getting here? I understand there are no surround elements in the film to decode, hence why there is no "Stereo Surround Mix" or some such rhetoric to play back in PL II; but IF the film is genuine MONO, why does the packaging not say "1.0" as other mono films (like MGM's "Amityville Horror") in my collection do?

[Quagmire]

"but IF the film is genuine MONO, why does the packaging not say "1.0" as other mono films (like MGM's "Amityville Horror") in my collection do?"

Because they have placed the mono track on two discrete channels; in this case the front left and right channels. In the example you used, "Amityville Horror" they chose to place the mono track on only one channel, probably the center channel.

Think of it like this... in days of old, if you went to a movie which was presented with a mono soundtrack, that didn't mean that there was only one speaker in the auditorium. The soundtrack may have been produced through two or more speakers even though it was only a mono track. Even though the track was mono, it may have been more easily heard by the entire audience when reproduced on multiple speakers. The same rationale may have gone into the decision to place the mono track on the front two channels of the DVD rather than on just the center channel. Regardless of how many channels it is played on, the track remains mono: Like I said in an earlier post, in theory you could have a 5.1 mono soundtrack but I doubt anyone would feel that there was any logical reason to do so. At least with a 2.0 mono track, it can be heard properly by those who own only a two channel stereo system as opposed to a full surround sound system. There have been many such mono recordings over the years which were made for playback on two channel systems - the format didn't find its beginning with the advent of DVD or Dolby Digital.

Q

[John Beresford]

Alright, Q...when you say this:

"Regardless of how many channels it is played on, the track remains mono: Like I said in an earlier post, in theory you could have a 5.1 mono soundtrack but I doubt anyone would feel that there was any logical reason to do so. At least with a 2.0 mono track, it can be heard properly by those who own only a two channel stereo system as opposed to a full surround sound system."


I understand what you are saying----like, the overall SIGNAL is MONO, and therefore it doesnt matter how many CHANNELS are playing the thing, it's still a MONO SOUND...much like the theory behind ALL CHANNEL STEREO mode on a receiver; although called stereo, you're actually just hearing ONE SIGNAL through each speaker, correct?

Now, while I can understand that, what do you mean that with a 2.0 mono track, it can be heard properly by those who own a two channel system? Are you saying that those folks with two channels in their stereo system can playback this disc and have it come from the two stereo channels (but in mono), but because in MY system, because I have a full 5.1 system and digital connection with a Pro Logic II decoder defaulting right away automatically, the receiver is collapsing the mono signal and sending it into the center channel only? Would this be why I can ONLY play these mono soundtracks through the center channel or through 2-channel stereo only?

[kelsci]

John; on your remote control to your Onkyo, do you have a buttom marked "stereo"? My Sherwood has that button. If I play a VHS Hi-Fi mono tape, that tape will have a mono soundtrack on the left and right hi-fi tracks(as well as a single mono track on the linear track). Therefore you have 2.0 analogue FM soundtracks. I have a Laserdisc Republic serial that has a mono recording on the left and right FM analogue tracks(call this 2.0 FM analogue soundtracks) as well as the left and right digital tracks(call this 2.0 16 bit digital tracks). These two machines are connected to two separate analogue inputs on the Sherwood(tape and aux). If I hit stereo on the Sherwood, the left mono track plays out of the left speaker; the right mono track plays out of the right speaker. You now have two independent 2 channel mono sound. Keep this in mind too. The audio from both the above machines are hooked up to the left and right analogue inputs.

Now we have a DVD player with a disc labled 2.0 dolby digital mono. This player is connected to the Sherwoods DVD analogue inputs. There is no PHYSICAL difference occuring as to these hookups of all three machines. Even if you outputted the 2.0 mono dvd through the coax or optical cable from the player, the receiver would still ouput two independent mono tracks.

The only way you would hear a non-mono sound from any of the above is if the receiver has a DSP usually called MONO MOVIE. It is a circuit that is a kind of "splitter" to create a "difference" in the sound on one or both of the channels. When a "difference" occurs, the receiver would then give you five channels from a mono source..

I think the answer to your mono question whether it be D.D. 1.0 or 2.0 steered to the center channel when the receiver is in DPL mode is DIFFERENCE and PHASING. Since the samples above have no difference or phasing(proof of that is listening the examples above; the audio is heard only between the speakers on your tv screen) the DPL chip recognizes the sound as sound that should be placed in the center and as such, in DPL we have the center channel speaker. 'Hope maybe this helps.

[Sir Terrence the Terrible]

I know this is a confusing issue, but just so we understand this 2.0 mono, and 1.0 mono areessentially the same thing just decoded differently. They are just listed carelessly. If we were listening to mono dialog from a 5.1 channel soundtrack all we would have to do is mix a discrete center channel only. Since we are talking prologic decoding, there is no discrete center channel. So information MUST be encoded equal level, and 0 degrees in phase into both the L and R discrete channels(much like Dolby stereo) in order for the decoder to derive a center channel signal. The 1.0 mono is essentially the same thing, except that the sound engineer used the discrete palate, and encoded the mono information in the center channel only WITHOUT dolby prologic decoding. So 2.0 mono is the same signal, mixed at the same volume, 0 in phase, and encoded into two channels to be decoded by prologic and directed to the center channel. 1.0 mono is the discrete version that uses only the center channel for the mono signal, and does not require any dolby prologic decoding to place the mono signal in the center channel.

Sir (head spinning in circles) Terrence

[Quagmire]

Don't you just love how John Beresford is a Junior Member here, whereas you and I are "site newbies". How long has it been since you thought of yourself as a site newbie?

Q

[John Beresford]

I know this is a confusing issue, but just so we understand this 2.0 mono, and 1.0 mono areessentially the same thing just decoded differently. They are just listed carelessly. If we were listening to mono dialog from a 5.1 channel soundtrack all we would have to do is mix a discrete center channel only. Since we are talking prologic decoding, there is no discrete center channel. So information MUST be encoded equal level, and 0 degrees in phase into both the L and R discrete channels(much like Dolby stereo) in order for the decoder to derive a center channel signal. The 1.0 mono is essentially the same thing, except that the sound engineer used the discrete palate, and encoded the mono information in the center channel only WITHOUT dolby prologic decoding. So 2.0 mono is the same signal, mixed at the same volume, 0 in phase, and encoded into two channels to be decoded by prologic and directed to the center channel. 1.0 mono is the discrete version that uses only the center channel for the mono signal, and does not require any dolby prologic decoding to place the mono signal in the center channel.

Sir (head spinning in circles) Terrence

Sir,

Yes, this is all very confusing, and I'm not really getting it, so I believe I am just simply forced to accept what the packaging says and just view mono DVDs via the center channel exclusively; I do understand, to a degree, what you are explaining about the mono/Pro Logic steering into one channel, but I still do not understand why MONO soundtracks are placed on TWO channels on some of these films to begin with, while other MONO films are designated in the (logical) 1.0---what happens to them after that I can accept (the two channels collapsing into the center via PLII, etc), but I do not understand why the marketing of the disc reads 2.0 channel mono to begin with; why mix on two channels if the result is mono? Then why not mix two channel stereo at that point?

I guess it is as was explained to me, that these 2.0 mono DVDs can be watched by those with 2-speaker/2-channel stereo only systems in a more enjoyable fashion than just out of their TV speakers; for folks like me, with a digital 5.1 surround system and a DVD connection made via optical digital cable, these 2.0 mono DVDs are being read by the Pro Logic II chip and being steered to the center speaker only.

[Quagmire]

Are you saying that those folks with two channels in their stereo system can playback this disc and have it come from the two stereo channels (but in mono), but because in MY system, because I have a full 5.1 system and digital connection with a Pro Logic II decoder defaulting right away automatically, the receiver is collapsing the mono signal and sending it into the center channel only? Would this be why I can ONLY play these mono soundtracks through the center channel or through 2-channel stereo only?

Yes.

Q

[John Beresford]

Yes.

Q

I wish I could tell you that this analysis made things easier to understand for me, but it didn't! LOL. But thank you for your help. I think I give up trying to understand this 2.0 mono issue; Im not really getting it, and I simply will accept the packaging on these discs for what they are and leave it be.

[kelsci]

John; Sir Terrence is an audio engineer. His explanation of this matter is as close as a non-technical, technical answer that you could have possibly received. I knew there was some phasing angle involved in this but I could not explain it since I do not quite possess his knowledge on the degrees of phasing. In fact, in the past I needed to ask him a question or two on phasing on other audio subjects.

I think it is best for you the choice you have made instead of chasing your "tail" to try to understand what is going on here. I think if you were personally shown a HANDS ON demonstration by somebody knowledgeable you would end up throwing a hat up into the air and end up saying; was this all that this really was? I have thrown the hat up a number of times in my life depending on the subject. I sat in an accounting class in high school in the 1960s for one year absofochlylutely wondering what was going on. Two years later, I went to night school for my mother heard there was a good teacher there teaching bookeeping. Well the first class was two or so hours long but when it was over, I could have have gotten an A 2 years earlier.

Take a rest from this mono concept for awhile. Sometimes you wake up one day and understanding of concepts hit you like a brick wall. This mono situation in not a life or death situation in your life. KELSCI.

[Quagmire]

You said: "...but I do not understand why the marketing of the disc reads 2.0 channel mono to begin with; why mix on two channels if the result is mono? Then why not mix two channel stereo at that point?"

First of all, I think you're right to just accept the packaging as is. It really isn't something worth getting all that worked up over. I actually get more upset when studios release fairly recent movies with only DPL soundtracks instead of remixing for true 5.1 surround; especially when they later release a "special edition" version of the movie with a remixed 5.1 soundtrack. Bill Murray's, "Ground Hog Day" is one such example, and although the movie isn't exactly a rollercoaster ride of sound effects, I would prefer to have the 5.1 mix. It's like penalizing those who like a particular movie and buy it early.

As far as your question regarding, "why not mix for stereo at that point?", as I said in an earlier post, the original soundtrack IS MONO and would require reworking of the soundtrack to make it stereo. Just placing the mono track in the two front channels does not require any rework of the original soundtrack. As for the earlier part of your question, "why mix on two channels if the result is mono?", I'm sure this is just a judgement call and besides, as I've said already, this really isn't a remix of the original soundtrack. Some may just feel that the track sounds better reproduced through the two front speakers and that for those with DPL systems, the sound will collapse to the center channel speaker anyway.

Q