12 replies to this topic

[#Darren]

Do you get better PQ by using an external stand alone digital tuner than you do by using the tuners in the TV?

[pgdownload]

Assuming you're using HDMI or component cables to connect the standalone unit then the answer is generally no. Some tuners in some TVs are a bit better, Some tuners in Some STBs are a bit better. Unless you're highly into getting the last few % improvement in PQ its unlikely you'd notice any difference. Use internal tuners if all you want to do is watch TV. Use PVRs (STBs with harddrives) if you want to control what you watch.

Regards

Peter Gillespie

[stefcep]

I think the Panasonic internal tuners give a too "soft picture", regardless of how much I play with the settings.  On an external Samsung  STB with hdmi, the picture quality improved noticeably.  I then let the magic grey smoke out of the STB and it stopped working, but thats another story.

[alanh]

Darren,
Only use internal tuners in TV for the following reasons
1. The TV remote will perform all functions and if you have a disc player or PVR connected by HDMI cable the one remote can control the whole system including playingand recording.
2. If you use the component output ie the red green and blue cables the picture quality is reduced because the TV will have to redigitise the analog signal so that it can be memorised to run the display.
3. TVs are much more reliable than any Set Top Box. For example the a large power supply to run all the electronics including the tuner. Where as STBs use the smallest power supply and usually the cooling of the processor microprocessor is poor causing them to die from excess heat.
4. The receiving section of the TV and the STB have to do te same things which is to demodulate and decompress the signals. These all have to follow strict mathematical rules. This makes tuners identical from this point of view.
5. There are 3 differences between any tuners
a. Will it decompress MPEG-4 compressed signals which is used for all 3D transmissions and is required for all new TVs, PVRs and STBs.
If not it will mean that some or eventually all program streams will be replaced with an error message
b. The sensitivity and ability to reject interference
c. The ability to demodulate DVB-T2 as well as DVB-t. DVB-t2 is used overseas but not in Australia yet, however it is the only way to increase the broadcast system to increase quality eg full HD 3D transmission or the adding of more programs.

AlanH

[DrP]

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1. The TV remote will perform all functions and if you have a disc player or PVR connected by HDMI cable the one remote can control the whole system including playingand recording.

Most HT enthusiasts realise that a 'TV' remote will not control all their equipment instead purchasing an aftermarket 'smart' remote.

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2. If you use the component output ie the red green and blue cables the picture quality is reduced because the TV will have to redigitise the analog signal so that it can be memorised to run the display.

Unless the TV has a particularly poor analogue stage this is usually not the case.

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3. TVs are much more reliable than any Set Top Box. For example the a large power supply to run all the electronics including the tuner. Where as STBs use the smallest power supply and usually the cooling of the processor microprocessor is poor causing them to die from excess heat.

Utter twattle.  TVs and STBs both use power supplies that are sized to do the job.  Both TVs and STBs can suffer from thermal stresses.  TVs break down as much as any other consumer electronics.  Anyone that has walked into a repair shop these days would see the plain truth.  The places are littered with defective TVs.

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4. The receiving section of the TV and the STB have to do te same things which is to demodulate and decompress the signals. These all have to follow strict mathematical rules. This makes tuners identical from this point of view.

More twattle.  Anyone that has any experience whatsoever with receivers in general will be fully aware that reception performance varies from device to device.  This is indicated on a daily basis by posts appearing on this forum.

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5. There are 3 differences between any tuners

Fascinating.  Only three?  You should write to all the equipment manufacturers!

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a. Will it decompress MPEG-4 compressed signals which is used for all 3D transmissions and is required for all new TVs, PVRs and STBs.

There is no requirement under Australian regulation for a receiver to support MPEG-4 AVC.  None.  The only organisation that requires MPEG-4 AVC support is 'freeview' and 'freeview certification is in no way compulsory.

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b. The sensitivity and ability to reject interference

Hmm.  This appears to contradict your point 4.  No surprise there, alanh contradicting himself.

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c. The ability to demodulate DVB-T2 as well as DVB-t. DVB-t2 is used overseas but not in Australia yet, however it is the only way to increase the broadcast system to increase quality eg full HD 3D transmission or the adding of more programs.

DVB-T2 is so far off that any equipment purchased today is more than likely going to be dead or retired by the time it comes around, if ever.  If a receiver comes with DVB-T2 support, it won't hurt, but purchasing equipment on the basis that it has DVB-T2 support is a fruitless exercise and may well end up costing more.


More sensible advice has already been provided by other forum members and that is the advice that should be heeded.

[MLXXX]

stefcep, on Jul 8 2011, 04:33 PM, said:

I think the Panasonic internal tuners give a too "soft picture", regardless of how much I play with the settings.  On an external Samsung  STB with hdmi, the picture quality improved noticeably.  I then let the magic grey smoke out of the STB and it stopped working, but thats another story.

Yes it is often reported that Panasonic sets of a year or two ago were designed to deliver a very soft picture when tuned to a standard definition signal. (This would have been an attempt to hide MPEG-2 coding artifacts, and is not a bad idea if the video signal is brodcast at a low bitrate.)

There's also a school of thought that some external devices provide superior upscaling for SD sources, than the upscaling built into a TV set. The upscaling may be "superior" by using advanced agorithms to enhance contrast without creating noticeable artifacts; and  to "correct" or "hide" artifacts in the source. An argument in the other direction is that the better latest model TV sets should include reasonably sophisticated upscaling anyway. The use of an external device would be a complication without yielding a significant improvement.

alanh, on Jul 9 2011, 08:22 PM, said:

Darren,
Only use internal tuners in TV for the following reasons
1. The TV remote will perform all functions and if you have a disc player or PVR connected by HDMI cable the one remote can control the whole system including playingand recording.

I think "can" should read "may possibly be able to".  Alanh, the functionality you describe is by no means guaranteed merely because connections use HDMI. For example, PVRs have been available for many years with HDMI output. That does not mean the PVR will accept control sigals via the HDMI interface.

Edited by MLXXX, 10 July 2011 - 11:44 AM.

[charlesc]

alanh, on Jul 9 2011, 08:22 PM, said:

These all have to follow strict mathematical rules. This makes tuners identical from this point of view.
AlanH

Tuners and their performance can and do vary quite a bit.
Even the way they recover the COFDM signal will vary according to the design of the proprietary chipsets that they use.
There's more than one way to do the job when it comes to transmitted data recovery.  And some methods no doubt work better than others.

You can't make statements like "This makes tuners identical from this point of view".  It's not correct.
Identical means something very specific.  'similar' means something else, but that wasn't used.  They're not interchangeable.

[mrdenn1s]

Inbuilt Tv tuners are definitely different

My Pio 507XDA easily and without issues takes my dodgy ABC signal from the antenna and displays the pic

My much newer LG7000 struggles with it

[digitalj]

mrdenn1s, on Jul 10 2011, 02:17 PM, said:

Inbuilt Tv tuners are definitely different

My Pio 507XDA easily and without issues takes my dodgy ABC signal from the antenna and displays the pic

My much newer LG7000 struggles with it

Maybe because LG stands for Low Grade?

[mtv]

digitalj, on Jul 10 2011, 08:19 PM, said:

Maybe because LG stands for Low Grade?     

Lucky (if it) Goes

[digitalj]

mtv, on Jul 10 2011, 11:52 PM, said:

Lucky (if it) Goes

Lucky (it's) Goldstar

[ekkieTHUMP]

I don't even understand this obsession with the best sd picture.I avoid it like the plague because it doesn't matter how silky you try and make the sows ear it doesn't change what it is.

[mwd]

I have an 07 60" Kuro and my Homecast 8000 PVR (HDMI) gives a significant PQ improvement compared to the internal tuner both SD and HD.