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Old 19-11-2009, 14:11
Valk
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I'm looking for a few opinions.
I am quite new to this so I can't make up my mind.
I have just invested in a new LCD TV, an LG-42LF7700.
I'm very happy with it and it comes with a vast array of connections.
I have a Panasonic Blue-ray and a Humax Freeview PVR connected by HDMI, a Pioneer DVD player connected by RGB scart and an Xbox connected with component connections used as a media center.
Works great except for the unimpressive sound quality from the flat screen audio.
The only output from the set is a digital audio out connector which it is claimed will output 5.1 sound.
I have Googled for more information on the digital audio and most reports don't rate it very highly but they all seem to be reports a good few years old.
Have things improved with this connector?
I am not looking for the bleeding edge of sound reproduction, I can't afford to, but all I want is a satisfactory audio experience when watching films, etc.
Is the only option an AV receiver?
If so, would a Digital audio connection to the receiver be OK or would I need to replug all my devices into the receiver and then input through only one HDMI connection to the TV?
Thanks for any advice before I revisit Richer Sounds.
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Old 19-11-2009, 14:47
chrisjr
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The digital audio out on the TV will more than likely just output Stereo. There are no terrestrial 5.1 surround sound TV broadcasts at the moment so the TV really doesn't need surround capabilities.

Anything you connect via SCART will be stereo only. Anything you connect via HDMI might be surround but equally it is likely to negotiate with the TV and send just stereo to it. And of course the TV may only feed the sound from it's internal tuner to the digital out, not whatever alternative input you are watching, (especially as SCART is analogue so would require analogue to digital conversion).

Your best option might be a proper AV amp and speaker system. A pair of systems I have quoted on other threads are...

http://www.richersounds.com/product/.../sony-strdh500
http://www.richersounds.com/product/...yama-nsp270-si

£240 ish

Or for something a bit more capable that lets you use the full audio capabilities of Blu-Ray

http://www.richersounds.com/product/...ky-txsr507-blk
http://www.richersounds.com/product/...ann-sfx5.1-blk

Which would come in at around £450.

In both instances you connect everything to the AV amp and let it take care of source selection. You may need the digital out from the TV to get sound from it's built in tuner.

Oh and don't take any notice of the rubbish written about optical digital being inferior to coaxial (via a phono socket). The two formats are identical in terms of the data they carry. Just that one uses pulses of light and the other pulses of electricity. There is absolutely no difference whatsoever in sound quality between the two.
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Old 19-11-2009, 15:16
Valk
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Thank you for all that. I appreciate your post.
The bit that had me thinking that I might get away with just using the Digital Out was this passage in the user manual -

"Sending the TV’s digital audio signal to external audio equipment via the Digital
Audio Output (Optical) port.
If you want to enjoy digital broadcasting through 5.1-channel speakers, connect the
OPTICAL DIGITAL AUDIO OUT terminal on the back of TV to a Home Theater (or
amp)"

but if the output is only stereo regardless of the audio input from the source, then connecting to an AV receiver has got to be favourite.
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Old 19-11-2009, 15:18
GaseousClay
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The digital audio out on the TV will more than likely just output Stereo. There are no terrestrial 5.1 surround sound TV broadcasts at the moment so the TV really doesn't need surround capabilities.
As the LG-42LF7700 has a freesat tuner the digital output will be capable of 5.1 surround, but only from BBC HD channel and 2 channel Dolby from ITV HD.
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Old 19-11-2009, 15:23
Valk
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As the LG-42LF7700 has a freesat tuner the digital output will be capable of 5.1 surround, but only from BBC HD channel and 2 channel Dolby from ITV HD.
Ah, that's interesting.
If the sound system in the TV is capable of 5.1 then will it pass through 5.1 from external equipment such as the Blue-ray player?
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Old 19-11-2009, 15:45
GaseousClay
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Ah, that's interesting.
If the sound system in the TV is capable of 5.1 then will it pass through 5.1 from external equipment such as the Blue-ray player?
I'm not 100% but I would think it only outputs from the freesat tuner and not pass through.
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Old 19-11-2009, 15:51
grahamlthompson
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Ah, that's interesting.
If the sound system in the TV is capable of 5.1 then will it pass through 5.1 from external equipment such as the Blue-ray player?
You will normally only get Dolby Digital out of a TV digital output if it's got a tuner that has a dolby digital source. EG a Freesat-HD one. Dolby Digital input from a seperate TV input will be downshifted to mpeg stereo. The spdif on the hdr will output mpeg1 - layer 2 stereo (which might have dolby surround info) for SD channels and Dolby Digital for HD channels so to use this you need an amplifier with a dolby digital decoder. BBC HD programming is a mixture of 5.1 and 2.0 DD and ITV HD currently is only in DD2.0 (Which is likely to have prologic surround sound info embedded)
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Old 19-11-2009, 15:59
chrisjr
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Ah, that's interesting.
If the sound system in the TV is capable of 5.1 then will it pass through 5.1 from external equipment such as the Blue-ray player?
I am struggling to find out exactly what comes out of the digital audio out on this TV. If i download the manual Adobe Reader locks up solid for some reason and the spec sheet on the LG website is useless.

And I cannot find anything about it online so far.

But bearing in mind you need an external amp and speaker system to make use of it you may as well hook everything directly to the AV amp which sort of makes it academic what comes out of the telly.
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Old 19-11-2009, 17:11
chrisjr
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Well I'm still no nearer an answer. Finally got the manual to stop locking up Adobe Reader.

Clear as mud really! The manual does not explicitly say what actually comes out of the Digital out. It mentions that you can set Dolby Digital or PCM and does mention that Dolby Digital will only be output if it is Broadcast. Which sort of implies it outputs the tuner audio.

But it does not anywhere that I can find mention what comes out if you are not using the tuners. There is some vague mention of HDMI mode and DVD players not outputting SPDIF in HDMI mode but what the hell it really means is anyone's guess.
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Old 19-11-2009, 17:18
grahamlthompson
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Well I'm still no nearer an answer. Finally got the manual to stop locking up Adobe Reader.

Clear as mud really! The manual does not explicitly say what actually comes out of the Digital out. It mentions that you can set Dolby Digital or PCM and does mention that Dolby Digital will only be output if it is Broadcast. Which sort of implies it outputs the tuner audio.
That's what my Sony TV instructions say and I can definitely say you never get Dolby Dig out as Freeview although supporting it never uses DD.
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Old 19-11-2009, 17:25
chrisjr
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That's what my Sony TV instructions say and I can definitely say you never get Dolby Dig out as Freeview although supporting it never uses DD.
But this telly is also Freesat equipped which does do Dolby Digital on a small number of channels.

But as I say the real sticking point is what comes out of the socket when you are watching the Blu-Ray player via HDMI?

PCM Stereo?
Dobly Digital 5.1?
DTS 5.1?
Silence?

The manual simply does not say. Nor does it say whether the TV has analogue to digital converters to output digital sound from sources connected by SCART.

But if it's connected to a decent AV amp then the whole thing is academic anyway as you would hook up all the sources direct to the amp. And only use the TV's digital out for TV sound from it's internal tuners. Which is about the only thing I can be 99% certain it will do!
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Old 19-11-2009, 17:41
Nigel Goodwin
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But this telly is also Freesat equipped which does do Dolby Digital on a small number of channels.

But as I say the real sticking point is what comes out of the socket when you are watching the Blu-Ray player via HDMI?

PCM Stereo?
Dobly Digital 5.1?
DTS 5.1?
Silence?

The manual simply does not say. Nor does it say whether the TV has analogue to digital converters to output digital sound from sources connected by SCART.
As far as I'm aware you only get 5.1 out from an HD channel using the internal Freesat tuner, anything going in the HDMI inputs (or from the internal Freeview tuner) is only stereo. None of the sets I've tried output anything at all from the digital output for analogue inputs.
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Old 19-11-2009, 17:43
Valk
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But if it's connected to a decent AV amp then the whole thing is academic anyway as you would hook up all the sources direct to the amp. And only use the TV's digital out for TV sound from it's internal tuners. Which is about the only thing I can be 99% certain it will do!
Thanks for all the input and I'm pretty settled that your way is the best way forward.
It is just that I have four different handsets and adding a fifth is likely to tip my wife over the edge as she has just got used to using the new TV controls to change peripherals.
Me too, come to that.
Can anyone recommend a very good Universal Controller?
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Old 19-11-2009, 17:54
GaseousClay
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It is just that I have four different handsets and adding a fifth is likely to tip my wife over the edge as she has just got used to using the new TV controls to change peripherals.

My other half counted the number of handset in our house couple of weeks ago...


25
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Old 19-11-2009, 18:23
Valk
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My other half counted the number of handset in our house couple of weeks ago...


25
I'll just tell the wife how lucky she is, then......

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Old 19-11-2009, 20:39
Nigel Goodwin
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Oh and don't take any notice of the rubbish written about optical digital being inferior to coaxial (via a phono socket). The two formats are identical in terms of the data they carry. Just that one uses pulses of light and the other pulses of electricity. There is absolutely no difference whatsoever in sound quality between the two.
No, to clarify even further - BOTH - are actually coaxial anyway. The coaxial signal in the source feeds a simple LED which outputs the optical signal. In the receiver, a simple photo-transistor converts the optical signal back to the original coaxial digital signal.

Optical is really just a gimmick, because people assume it's the signal directly off the optical disc.
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Old 19-11-2009, 20:59
crowby1
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Sorry to piggy back on this thread but I have a similar question.

My Sky+ is connected via Scart to my Panasonic tv and the tv is connected to the Panasonic surround system via two phono plugs.

I watched Die Hard 4.0 (channel five) on this last week and it sounded pretty convincing suround sound to me.

Am I not getting true surround sound with this connection?
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Old 19-11-2009, 21:02
bobcar
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Optical is really just a gimmick, because people assume it's the signal directly off the optical disc.
I never realised anyone thought that, makes the re-gassing of plasmas seem sensible.
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Old 19-11-2009, 21:48
chrisjr
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Sorry to piggy back on this thread but I have a similar question.

My Sky+ is connected via Scart to my Panasonic tv and the tv is connected to the Panasonic surround system via two phono plugs.

I watched Die Hard 4.0 (channel five) on this last week and it sounded pretty convincing suround sound to me.

Am I not getting true surround sound with this connection?
No.

You are just getting stereo. To get true surround sound requires six channels, ie six analogue phono plugs or a digital connection.

The very best you will get is Dolby Pro Logic. Either encoded into the stereo signal or generated in the surround system. Pro Logic effectively fabricates the surround signals by applying some clever trickery to the stereo signal.

This process can be made more effective by specially encoding the stereo signal with additional information. But it cannot really match a true Dolby Digital or DTS surround sound signal.
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Old 19-11-2009, 21:56
chrisjr
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No, to clarify even further - BOTH - are actually coaxial anyway. The coaxial signal in the source feeds a simple LED which outputs the optical signal. In the receiver, a simple photo-transistor converts the optical signal back to the original coaxial digital signal.

Optical is really just a gimmick, because people assume it's the signal directly off the optical disc.
Many years ago I took the lid off one of the very first Sony DAT recorders the DTC-1000. It was a work of art with loads of copper screens between various parts of the unit.

Anyway on the main audio board you could clearly see the optical and coaxial output sockets . And the PCB tracks connecting them. Follow the tracks back and you came to a pair of resistors one end connected to each socket and the other ends joined together and leading back to an IC that was the output driver.

So it really was a case that both optical and coaxial outputs were exactly the same since the two were ultimately wired to the same place.
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Old 19-11-2009, 21:59
crowby1
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No.

You are just getting stereo. To get true surround sound requires six channels, ie six analogue phono plugs or a digital connection.

The very best you will get is Dolby Pro Logic. Either encoded into the stereo signal or generated in the surround system. Pro Logic effectively fabricates the surround signals by applying some clever trickery to the stereo signal.

This process can be made more effective by specially encoding the stereo signal with additional information. But it cannot really match a true Dolby Digital or DTS surround sound signal.
I've now outputted my Sky+ box directly to the surround box using the optical digital connector that I got sold with the system. Proper Surround now?

Sky does broadcast a surround signal? I keep reading digital terrestial signals are stereo only. Sky is different?
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Old 19-11-2009, 22:15
chrisjr
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I've now outputted my Sky+ box directly to the surround box using the optical digital connector that I got sold with the system. Proper Surround now?

Sky does broadcast a surround signal? I keep reading digital terrestial signals are stereo only. Sky is different?
It all depends on the broadcast. I suspect the vast majority of channels are stereo. You are more likely to get true surround on the movie channels.

You can check this by pressing the Sky and i buttons and looking for the letters DD topright of the information banner.
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Old 19-11-2009, 23:40
frasera
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is it really that bad there? most stuff in hd here broadcast is in surround:P

but yes, built in speakers on flat tvs are junk. you can only fit so much into a unit that thin.
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Old 19-11-2009, 23:46
Greebo
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Many years ago I took the lid off one of the very first Sony DAT recorders the DTC-1000. It was a work of art with loads of copper screens between various parts of the unit.
This wee beastie: http://www.niji.or.jp/home/k-nisi/dtc-1000es.htm - I had one as a student back in the late 80's - even with the wooden side panels - amazing machine. It was modified by HHB* - the timer switch was rewired to allow me to set the sampling freq to 44.1kHz to make CD masters, rather than the usual 48kHz that DAT used. Sadly I had to give it back when that project was completed

*My memory is foggy - HHB could be slightly wrong here.
** Apologies for the sidetrack!
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Old 20-11-2009, 07:41
Nigel Goodwin
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So it really was a case that both optical and coaxial outputs were exactly the same since the two were ultimately wired to the same place.
It's the same on everything, optical and coaxial are just the same signal.
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