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iiggoorr
02-09-2010, 12:39 AM
Hi,

So i have lg dvx492H dvd player and it is connected with my lg sl8000 TV set via HDMI cabel.
My problem is I cant get Dolby 5.1 audio Chanel from any DVD. Only 2.1 and 2.0 channels are available.
I tried it with bit stream as well as with PCM audio output. I have also tried changing sampling frequency from 48khz to 96khz but with no luck.

The reason i would like to have available 5.1 audio channel is sl8000 is equipped with srs tru surround and i would like to use it.
Please don't argue that srs truesurround is not good because that is not the point of this question.

So is no 5.1 audio channel via HDMI normal thing, and if it is how can i get 5.1 audio channel in my TV set, or is it a malfunction?

THX in advnced

markw
02-09-2010, 03:14 AM
I don't think you can pass 5.1 digital audio to or through a TV set. Try connecting the DVD player directly (via either coax or toslink) to the receiver.

iiggoorr
02-09-2010, 03:29 AM
thank you for the replay.
The thing is I don't have reciver or the home cinema system, but my TV set LG sl8000 have dd decoder so I think it should accept dd 5.1 audio.
As I mentioned I would like to have dd 5.1 audio because TV has SRS truesurround which I would like to use as a supstent for home cinema system

poppachubby
02-09-2010, 03:34 AM
Dolby decoding is different than multi channel. The TV is doing what it's supposed to do. It recognizes the digital input and is outputting the only way it can, in 2.0. 2 speakers on a TV...

As far as Dolby or SRS, the TV shouldn't have any issue outputting this if it's capable.

I'm not familiar with your TV set, but I would be surprised if it's able to decode multi channel. You need a receiver, there's no way around it.

iiggoorr
02-09-2010, 03:57 AM
Well, i am begining to understand that I have understood some specificaton wrong.
But just for clarification If SRS truesurround is a system/algoritam that is capable of reproducing 5 audio chanels on just two speakers creating lets call it virtual 5.1 audio

and if my TV audio specificatiion list is as follows:

Audio Output10W + 10W Speaker System1 Way 2 Speakers
Dolby Digital Decoder Yes
Surround System SRS Trussurond

should it not then recive dd 5.1 audio and use SRS to create that virtual 5.1 effect?

Thanks for makeing me undersand

frahengeo
02-09-2010, 06:04 AM
Well, i am begining to understand that I have understood some specificaton wrong.
But just for clarification If SRS truesurround is a system/algoritam that is capable of reproducing 5 audio chanels on just two speakers creating lets call it virtual 5.1 audio

and if my TV audio specificatiion list is as follows:

Audio Output10W + 10W Speaker System1 Way 2 Speakers
Dolby Digital Decoder Yes
Surround System SRS Trussurond

should it not then recive dd 5.1 audio and use SRS to create that virtual 5.1 effect?

Thanks for makeing me undersand

I believe that your TV is capable of sending a Dolby Digital 5.1 signal to a receiver via the TV optical output. The Dolby Digital receiver will then send power to at least 5 different speakers as well as a signal for the subwoofer. The "surround" effect will depend on the placement of those 5 speakers.

The SRS Trusurround will take the 5.1 signal and attempt to simulate the surround effect using just two speakers. However, SRS does not come remotely close to actual 5.1 surround.

Hope this helps

pixelthis
02-09-2010, 12:26 PM
I believe that your TV is capable of sending a Dolby Digital 5.1 signal to a receiver via the TV optical output. The Dolby Digital receiver will then send power to at least 5 different speakers as well as a signal for the subwoofer. The "surround" effect will depend on the placement of those 5 speakers.

The SRS Trusurround will take the 5.1 signal and attempt to simulate the surround effect using just two speakers. However, SRS does not come remotely close to actual 5.1 surround.

Hope this helps

Every TV I have ever seen has a digital output for the tuner only.
SRS works on two channels, it creates an effect that seems like suround,
but isnt.
I had a similar effect from a computer sound card once, kinda weird having sound come from nowhere, and Bose has beed peddeling their version for years.
It will work, but so does a bike, dont wanna ride one to work ten miles every day.
WORK ON GETTING AT LEAST a home theater in a box, or a set of sub-sat computer speakers.
AT LEAST.:1:

iiggoorr
02-09-2010, 12:27 PM
The SRS Trusurround will take the 5.1 signal and attempt to simulate the surround effect using just two speakers. However, SRS does not come remotely close to actual 5.1 surround.
Hope this helps

This is helpful in a way that it confirms my theory which is that the tv should receive 5.1 audio channel and than using SRS do with it what it can. But now I am back to the my original question.

Why can't I select 5.1 audio channel in audio setup of the DVD... For some reason only available audio channels are 2.0 and 2.1. I am sure that at least some of the DVDs I tried have dd 5.1 audio channel since it is written so on the boxes :)

iiggoorr
02-09-2010, 12:35 PM
Every TV I have ever seen has a digital output for the tuner only.
SRS works on two channels, it creates an effect that seems like suround,
but isnt.


according to the definition of SRS your definition is not right...

here is the definition from http://hometheater.about.com/od/home...urrounddef.htm

Tru-Surround XT is a sound-scheme that has the ability to take multi-channel encoded sources, such as Dolby Digital, and reproduce the multi-channel surround effect by just using two-speakers. The result is not as impressive as true Dolby Digital 5.1 (the front and side surround effects are impressive, but the rear surround effects fall a little short, with the sense they are coming from just to rear of your head rather than from the back of the room).


So in a way it is opposite from what you are describing.

System that creates 5 channels out of two is for instance Dolby pro logic.
SRS is trying to reproduce 5 channels with only two speakers...

But that is not the point.

My original question was why can't I choose 5.1 audio channel in audio setup of DVDs that do have dd 5.1... I have only 2.0 and 2.1 channels available for choosing from

BadAssJazz
02-09-2010, 01:23 PM
Did you turn off Clear Voice II? SRS Trussurround XT won't work, if you have Voice activated... according to the manual.

Woochifer
02-09-2010, 02:07 PM
I believe that your TV is capable of sending a Dolby Digital 5.1 signal to a receiver via the TV optical output. The Dolby Digital receiver will then send power to at least 5 different speakers as well as a signal for the subwoofer. The "surround" effect will depend on the placement of those 5 speakers.

The SRS Trusurround will take the 5.1 signal and attempt to simulate the surround effect using just two speakers. However, SRS does not come remotely close to actual 5.1 surround.

Hope this helps

Actually, the digital audio output from a TV is often transcoded to PCM and output as a two-channel signal. I believe this is a licensing issue, as the Dolby Digital signal is allowed to be either transcoded or otherwise decoded for output through the TV speakers. But, most TVs are not licensed to retransmit the Dolby Digital signal through the digital audio output, so they will output a two-channel PCM signal instead.

frahengeo
02-09-2010, 04:45 PM
Actually, the digital audio output from a TV is often transcoded to PCM and output as a two-channel signal. I believe this is a licensing issue, as the Dolby Digital signal is allowed to be either transcoded or otherwise decoded for output through the TV speakers. But, most TVs are not licensed to retransmit the Dolby Digital signal through the digital audio output, so they will output a two-channel PCM signal instead.

Besides being able to use better speakers for the 2-channel output, what would be the point for the optical out then? A marketing ploy? Are there any other algorithms of 5.1 sound besides Dolby or DTS?

Mr Peabody
02-09-2010, 07:36 PM
If the TV is to process the signal you want "bitstream". SRS does lead you to believe they will accept a 5.1 signal http://www.srslabs.com/content.aspx?id=162 unfortunately I don't have the answer.

pixelthis
02-10-2010, 02:22 PM
according to the definition of SRS your definition is not right...

here is the definition from http://hometheater.about.com/od/home...urrounddef.htm

Tru-Surround XT is a sound-scheme that has the ability to take multi-channel encoded sources, such as Dolby Digital, and reproduce the multi-channel surround effect by just using two-speakers. The result is not as impressive as true Dolby Digital 5.1 (the front and side surround effects are impressive, but the rear surround effects fall a little short, with the sense they are coming from just to rear of your head rather than from the back of the room).


So in a way it is opposite from what you are describing.

System that creates 5 channels out of two is for instance Dolby pro logic.
SRS is trying to reproduce 5 channels with only two speakers...

But that is not the point.

My original question was why can't I choose 5.1 audio channel in audio setup of DVDs that do have dd 5.1... I have only 2.0 and 2.1 channels available for choosing from

Its not that different.
WHEATHER a synthisized surround channel or a real channel processed for fake surround, the effect usually is the same.
AS FOR YOUR DVD player, its either the output you choose, the format of the output
(bitstream, pcm) thats mesing you up:1:

pixelthis
02-10-2010, 02:34 PM
Another possibility is that if you're passing it through your TV, you might not be able
to get a sound without it being downconverted to either 2.0 or 2.1, either by the TV or
player.
Maybe your player is talking to your TV and automatically downconverting.
When I GOT MY NEW RECEIVER I ran everything through it, to get video switching.
But it wouldnt output anthing but 2.0, 44.1 kz.
Turns out it was set to "tv" sound, so that the output would only play 2.0 at the HDMI out,
assuming it was hooked up to a TV!
It took 130 pages to find this little "feature" and disable it.
Sometimes theres nothing for it but to read the manuel.:1:

Mr Peabody
02-10-2010, 07:59 PM
Pix, you have a point about reading the manual. I suspect it's something like Badass was talking about. Some little quirk. I have that SRS or something similar on my Sony TV and know it don't work when certain other features are selected. That's the wife/kids TV so I don't remember the particulars.

iiggoorr
02-10-2010, 10:50 PM
Thanks for the advices. I did read the manual, more than once :), but it is possible that I have missed something... So i will look it once again.

In a mean while other suggestions are welcome

Mr Peabody
02-11-2010, 06:29 AM
What you might try is submitting your question to the manufacturer website to see how they respond. This has worked out on occasion but others you wonder why they bothered responding :)

pixelthis
02-11-2010, 01:34 PM
Pix, you have a point about reading the manual. I suspect it's something like Badass was talking about. Some little quirk. I have that SRS or something similar on my Sony TV and know it don't work when certain other features are selected. That's the wife/kids TV so I don't remember the particulars.

Yea, its funny how sometimes the "simple" setup gives the most problem.
Maybe I AM MISSING SOMETHING...
but so what if hes only getting 2.0 or 2.1?
Not going to make much difference, not really.:1:

Mr Peabody
02-11-2010, 06:13 PM
IIGGOORR, do you know any one else with a BD player you can try or you can take yours to hook up to another unit to see if it outputs 5.1 to their unit?

iiggoorr
02-11-2010, 11:15 PM
Yea, its funny how sometimes the "simple" setup gives the most problem.
Maybe I AM MISSING SOMETHING...
but so what if hes only getting 2.0 or 2.1?
Not going to make much difference, not really.:1:

No, unfortunately I didn't miss anything :).
And I guess you are right I don't believe that 5.1 channel would be a great improvement over two channels.

The thing is when there is a "problem" with electronic appliances I want to solve it, or at least I won't to know that the problem is actually not a problem, because everything is working as it should.

Someone suggested that I contact manufacturer, which I did before writing here, but I didn't get any answer from them. I tried LG UK and LG Croatia :).

Now I am thinking that DVD player wasn't meant to send multichannel audio over HDMI... after all why should it do so...
What I mean is DVD doesn't support Dolby true HD and other HD audio formats which actually require HDMI connection, so digital coaxial or optical audio connection is actually enough.
The problem is I have only something called RGB/DVI and SCART audio inputs, so I guess there is no way to have 5.1 audio in my TV set...

Thank you all for your comments and suggestions.

Feel free to comment on my theory :).

BTW what the hack is RGB/DVI audio input, and as silly as it may sound to you, is it maybe compatible with digital coaxial audio in some way?

Mr Peabody
02-12-2010, 06:29 AM
Yeah, manufacturers vary in customer service. I never get a response from Samsung. They do alright if you call them but they don't answer email apparently.

HDMI does send 5.1 bitstream from DVD or Blu-ray. If anything maybe we are misunderstanding how SRS works and the TV only accepts the 2.0. There could be a technical problem but unless you can try your player with another unit that accepts HDMI or try another unit with your TV we may not know.

I fully understand you wanting to figure out the mystery. Issues like what you have drive me crazy too.

bobsticks
02-12-2010, 06:55 AM
There could potentially be a handshake problem between HDMI connections if they are different versions.

iiggoorr
02-12-2010, 11:33 AM
There could potentially be a handshake problem between HDMI connections if they are different versions.

Well this might be it. The DVD have HDMI 1.0 and the TV set have HDMI 1.3.

If there is a handshake problem is it solvable, is there a way to upgrade DVD to HDMI 1.3 maybe with firmware update?

pixelthis
02-12-2010, 01:42 PM
No, unfortunately I didn't miss anything :).
And I guess you are right I don't believe that 5.1 channel would be a great improvement over two channels.

The thing is when there is a "problem" with electronic appliances I want to solve it, or at least I won't to know that the problem is actually not a problem, because everything is working as it should.

Someone suggested that I contact manufacturer, which I did before writing here, but I didn't get any answer from them. I tried LG UK and LG Croatia :).

Now I am thinking that DVD player wasn't meant to send multichannel audio over HDMI... after all why should it do so...
What I mean is DVD doesn't support Dolby true HD and other HD audio formats which actually require HDMI connection, so digital coaxial or optical audio connection is actually enough.
The problem is I have only something called RGB/DVI and SCART audio inputs, so I guess there is no way to have 5.1 audio in my TV set...

Thank you all for your comments and suggestions.

Feel free to comment on my theory :).

BTW what the hack is RGB/DVI audio input, and as silly as it may sound to you, is it maybe compatible with digital coaxial audio in some way?

Your like the guy, kept messing with his car.
It was a Dodge, a lost cause and a waste of time, basically.
Even if you do solve the "problem" what are you left with?
Some stuff is made "broken", the only tool that will "fix" it is the nearest dumpster.:1:

iiggoorr
02-12-2010, 01:55 PM
Your like the guy, kept messing with his car.
It was a Dodge, a lost cause and a waste of time, basically.
Even if you do solve the "problem" what are you left with?
Some stuff is made "broken", the only tool that will "fix" it is the nearest dumpster.:1:


And the point is....

neither my TV or DVD are for dumpster.
No I do not have modern AV recieve with dd or DTS decoder.
Yes I want to make the most of what I have...
So please be constructive or be quiet...

Sir Terrence the Terrible
02-12-2010, 02:49 PM
iiggoorr,
Let me take a crack at this. First, your DVD player is probably sending out a Dolby Digital stream, but the television does not decode the 5.1 mix, it mixes it down to 2.0. This is correct in that your television does not have 6 speakers to decode the multichannel stream, so the internal decoder folds the surrounds and center into thye 2.0 stream. The .1 channel is discarded completely in this case.

SRS truesurround does not output as a 5.1 signal. It takes the downmixed 2.0 digital stream and through phase manipulation and timing algorythms it attempts to recreated the 5.1 channel experience, add clarity to the dialog using a EQ boost in the voice freqencies, and optimize the bass to compensate for the loss of the LFE channel to downmixing using dynamically adjustable bass boost that works to keep bass full sounding even when the volume is lowered. It is a simulated effect that when you move off axis of center, it disappears.

Just set your DVD player to 5.1 or 2.0. It will go through the set, be downmixed(if 5.1), and you can engage the Tru-surround XT to turn the 2.0 signal into faux 5.1.

I hope that helps ya.

P.S. Sorry you had to deal with the village idiot, but we all have this cross to bare.

iiggoorr
02-13-2010, 07:03 AM
iiggoorr,
Let me take a crack at this. First, your DVD player is probably sending out a Dolby Digital stream, but the television does not decode the 5.1 mix, it mixes it down to 2.0. This is correct in that your television does not have 6 speakers to decode the multichannel stream, so the internal decoder folds the surrounds and center into thye 2.0 stream. The .1 channel is discarded completely in this case.

SRS truesurround does not output as a 5.1 signal. It takes the downmixed 2.0 digital stream and through phase manipulation and timing algorythms it attempts to recreated the 5.1 channel experience, add clarity to the dialog using a EQ boost in the voice freqencies, and optimize the bass to compensate for the loss of the LFE channel to downmixing using dynamically adjustable bass boost that works to keep bass full sounding even when the volume is lowered. It is a simulated effect that when you move off axis of center, it disappears.

Just set your DVD player to 5.1 or 2.0. It will go through the set, be downmixed(if 5.1), and you can engage the Tru-surround XT to turn the 2.0 signal into faux 5.1.

I hope that helps ya.

P.S. Sorry you had to deal with the village idiot, but we all have this cross to bare.


Thank you very much for explanation...

I am more and more convinced that your explanation is correct.
I am still a bit confused about SRS true surround because on the SRS web page the explanation of the system is that it takes 5 audio channel and reproduce it over 2 channels thus creating virtual surround... So as i understood it SRS true surround is black box with 5 channel input and 2 channel output...

But here is the question... I am using DVD to select audio chanel/source... and DVDs audio is selected to bit stream mode. So why is DVD down converting multichannel audio to 2.1 mode. Wouldn't it be correct to reproduce multichannel audio and to let the connected device to deal with it. :).
I mean this why SRS "black box" can't use 5 channel input and do its job...

Sir Terrence the Terrible
02-13-2010, 08:46 AM
Thank you very much for explanation...

I am more and more convinced that your explanation is correct.
I am still a bit confused about SRS true surround because on the SRS web page the explanation of the system is that it takes 5 audio channel and reproduce it over 2 channels thus creating virtual surround... So as i understood it SRS true surround is black box with 5 channel input and 2 channel output...

You got it!


But here is the question... I am using DVD to select audio chanel/source... and DVDs audio is selected to bit stream mode. So why is DVD down converting multichannel audio to 2.1 mode. Wouldn't it be correct to reproduce multichannel audio and to let the connected device to deal with it. :).
I mean this why SRS "black box" can't use 5 channel input and do its job...

Are you sure it is downcoverting? Is it telling you it is outputting a 2.1 stream? If so, there is something missing here.

If you are sending the audio via HDMI to the television, you cannot know that it is downconverting unless you make that choice, or you are missing a output setting. If you tell the DVD player to send a 5.1 signal to the television, it should do exactly that. There should be no down conversion taking place.

Mr Peabody
02-13-2010, 07:08 PM
IIggoor, what is the model number of your LG player?

pixelthis
02-14-2010, 01:26 AM
And the point is....

neither my TV or DVD are for dumpster.
No I do not have modern AV recieve with dd or DTS decoder.
Yes I want to make the most of what I have...
So please be constructive or be quiet...

The point is don't worry about it.
Even if you do get it to work, what have you got?
What have you learned?
You can get a cheap HTIB that will probably sound better.
In other words, you are like the guy on this site that is rebuilding a pair of
Bose 901's, the question being why?
I think you've been messing with this so long, you have to step back and ask that
simple question...why?
Is it worth the trouble?
After getting caught up in a few dead end projects like this one, I now stop and ask
myself that question every once in awhile.
:1:

iiggoorr
02-14-2010, 01:35 AM
You got it!
If you are sending the audio via HDMI to the television, you cannot know that it is downconverting unless you make that choice, or you are missing a output setting. If you tell the DVD player to send a 5.1 signal to the television, it should do exactly that. There should be no down conversion taking place.

Well here is the situation... I can not even chose the 5.1 audio channel... I can only chose from 2.1 and 2.0 audio options, and that choosing is done on DVD. Just for the information I am certain that DVDs I tried do have 5.1 audio.

I have made a little test... I copied one DVD, and I have chosen to copy only DD 5.1 audio.
When i insert that copied DVD in to the player, the only available audio is again DD 2.1.

So I guessed that DVD is automatically down converting it...

iiggoorr
02-14-2010, 01:37 AM
IIggoor, what is the model number of your LG player?

I have LG DVX492H and it is connected to LG 32SL8000 TV SET via HDMI 1.3 compatible cable...

Sir Terrence the Terrible
02-14-2010, 01:16 PM
I have LG DVX492H and it is connected to LG 32SL8000 TV SET via HDMI 1.3 compatible cable...

Okay now this make sense to me. The HDMI protocol see's only the televisions speaker set it is transmitting audio to, that is why it downmixes before coming out of the player. If the HDMI signal communicates with a receiver, then it will give YOU the choice of 5.1 or 2.0.

HDMI is a two way protocol that send out signals to identify the device it is communicating with. So when you set up your Bluray player, it send out a signal to ask whether the device is a 720p, 1080i. or 1080p source, and when the source communicates back what it is, the HDMI protocol will automatically set the resolution. This happen with video as well as audio, and since your television can only do stereo, that is what the protocol see's, and that is what it scales the audio to.

There is nothing wrong with your set up. You should still be able to engage the SRS signal even with two channels, and it will simulate(or should) Dolby surround(Lt/Rt), not 5.1 channel surround. The effect in the end will be pretty much the same.

iiggoorr
02-14-2010, 10:58 PM
Sir Terrence the Terrible...

Thank you very much for excelent explanation, I understand it complitly now and I can stop worrying that something is wrong with either my TV or DVD...

Thanks...

pixelthis
02-14-2010, 11:58 PM
Sir Terrence the Terrible...

Thank you very much for excelent explanation, I understand it complitly now and I can stop worrying that something is wrong with either my TV or DVD...

Thanks...

WHAT I SAID on 2-10, 2010.
Probably where sir talky got it from.:1: