Home cinema - HDTVs and audio

HomeCinemaBanter (http://www.homecinemabanter.com/index.php)

- UK digital tv (http://www.homecinemabanter.com/forumdisplay.php?f=5)

- - HDTVs and audio (http://www.homecinemabanter.com/showthread.php?t=73978)

On Thu, 02 Jan 2014 11:11:43 +0000, Andy Burns wrote:

Jim Lesurf wrote:

Using the TVs 'volume control' something I'd tend to avoid if possible as I
have no idea how well it can scale the values.

My TV just seems to send "+" and "-" commands to the amp rather than
absolute values, my amp is set for a 0-100 scale with 0.5 unit steps
which is finer than the TV's inbuilt volume control (0 to 63 I think)
the amp has the option of using a dB scale but my brain doesn't
naturally use logs.

Be glad that you're not using the volume control on the Humax Freesat PVR -
5% steps!
--
Peter.
The gods will stay away
whilst religions hold sway

Jim Lesurf wrote:

FWIW I simply take the audio from the 'headphone' jack on the (Sony) TV.
The telly is set for the internal speaker to be muted. This works
perfectly for analogue and digital reception, reception via scart and
HDMI. Full control of volume and no sync problems. If I compare Swiss
Classic direct or via the telly there's no difference that I can tell.

The only TV I've ever had with almost decent analogue audio output was a
B&O one decades ago. Alas monophonic 4:3. The analogue output from other
sets seems always to give hum problems, background noise, distorted peaks,
etc. So I regard the analogue sound circuits in TVs as best avoided.

It could be that your opinion is based on the use of old CRT sets. I
have absolutely no issues with the analogue audio from my new Sony. And
I am very critical.

Does "the internet" always come and take away my old CRT so I don't even
have to try and lift it? I expect John Lewis probably do, but I'm less sure
about the tax dodgers.

I suppose if you don't have any helpful friends or neighbours you should
weigh up any extra cost incurred by using the local firm versus the cost
of disposing of the old set. Won't the council take it? If it still
works won't you be putting it in a bedroom, or using Freecycle?

Bill

In article , Bill Wright
wrote:
Jim Lesurf wrote:

FWIW I simply take the audio from the 'headphone' jack on the (Sony)
TV. The telly is set for the internal speaker to be muted. This works
perfectly for analogue and digital reception, reception via scart and
HDMI. Full control of volume and no sync problems. If I compare Swiss
Classic direct or via the telly there's no difference that I can tell.

The only TV I've ever had with almost decent analogue audio output was
a B&O one decades ago. Alas monophonic 4:3. The analogue output from
other sets seems always to give hum problems, background noise,
distorted peaks, etc. So I regard the analogue sound circuits in TVs
as best avoided.

It could be that your opinion is based on the use of old CRT sets.

About 10 years old.

As I said, the previous set (B&O) was better in general audio terms and
would drive a fair external speaker. No noise from the speakers when the
volume was wound down, etc. But it was monophonic analogue 4:3 of the
pre-scart generation. So we replaced it when digital came along...

Does "the internet" always come and take away my old CRT so I don't
even have to try and lift it? I expect John Lewis probably do, but I'm
less sure about the tax dodgers.

I suppose if you don't have any helpful friends or neighbours you should
weigh up any extra cost incurred by using the local firm versus the cost
of disposing of the old set.

Plus, of course, the wish to see some of the profit 'stay local' with
ordinary shops rather tha be taken afar by big companies who may also do
things like dodge tax. Surprised if you don't understand that someone might
prefer to support local small businesses and employment if they can do the
job OK. Particularly to help ensure they will be there when we buy other
more day-to-day items However in the end I'll decide on the basis of what
they offer and if it suits. If they don't have something we like, I'll look
elsewhere. Probably JL being the next port of call as there aren't any
other local shops for TVs.

Won't the council take it? If it still
works won't you be putting it in a bedroom, or using Freecycle?

The council would take it from the kerbside for 25 quid. But I can't even
lift it, let alone carry it that far. Nor could I plus better-half. Totally
out of the question to carry it up the stairs even if we wanted a TV that
size up there! In fact, I'd fear for the floor upstairs as its a loft
conversion.

Jim

--
Please use the address on the audiomisc page if you wish to email me.
Electronics http://www.st-and.ac.uk/~www_pa/Scot...o/electron.htm
Armstrong Audio http://www.audiomisc.co.uk/Armstrong/armstrong.html
Audio Misc http://www.audiomisc.co.uk/index.html

On Thu, 02 Jan 2014 04:45:49 -0600, "Steve Thackery"
wrote:

Johny B Good wrote:

With mpeg compression, the edges of the transmitted picture will
exhibit compression artifacts at a noticably higher level than
elsewhere.

Are you sure? The edges? That's not my experience as a viewer
(although I don't know anything much about the MPEG compression
algorithm).

As a viewer, the compression artefacts become most obvious on large
areas of similar colour which move, such as mist. I certainly haven't
spotted anything odd about the edges.

That's possibly due to your attention being drawn away from the edges
by the compression artifacts you've so accurately observed (tempted as
I am, I'll not raise any 'conspiracy theories' about 'distraction
techniques' being used by the mpeg codecs).

Could you provide a reference for me to read up more about it?

I'm afraid I can't. You'll just have to scrutinise the edges of mpeg
material more closely than usual. You should see the effect soon
enough (most apparent with largish areas of mid luminence colour tones
that are cropped by the frame edge).

The effect seems most pronounced on the side edges but is still, to a
less obvious degree, present at the top and bottom edges of the frame.

You won't, as a matter of course, be able to observe the effect if
the display is 'overscanning' the transmitted frame beyond the edges
of the display area. Your best chance of seeing picture content right
out to the edges of the trasmitted picture is to use a computer to
playback the movie file.

Once you've tried this exercise in observation, you'll be able to
better relate to the use of 'overscanning' in a modern day TV sets
when you come to google for references to this effect.
--
Regards, J B Good

I'll probably buy the TV from a local shop if they have what I want.
Otherwise I may look to John Lewis to get one. Either way, I'll need
them to also cart away my old CRT set (analogue). I can't even lift
that, let alone put it out for collection!

John Lewis will take away your old set for £9 if you buy a large screen
TV (37" or over).

--
Robin
reply to address is (meant to be) valid

Johny B Good wrote:

Once you've tried this exercise in observation, you'll be able to
better relate to the use of 'overscanning' in a modern day TV sets
when you come to google for references to this effect.

Well, I don't use overscanning. All of my viewing is in HD where
possible, and I have the TV set to pixel-to-pixel mapping at all times.

To be honest I don't notice any of the typical compression artefacts in
HD, but I do get annoyed at how "soft" they've made the pictures
(presumably to reduce the bandwidth requirements). They aren't
*really* 1920 x 1080, because the fine details smooth out at a far
larger scale than the individual pixels. They're just transmitted as
such.

--
SteveT

"Andy Burns" wrote in message
o.uk...
Richard Tobin wrote:
Jim Lesurf wrote:

1) Is it standard for such sets to accept audio in via HDMI and then
copy
that out via an SPDIF coax/optical outlet for connection to a decent
external DAC?

An alternative, depending on your audio equipment, is to send the
output by HDMI too, using the audio return channel.

Then you're at the mercy of whatever DAC in in the amp,

true, but if you can spot it, you must have pretty good ears.

it also requires HDMI 1.4 support in TV and amp, not likely to be an issue
for new kit.

true, then use optical or coax.

This has the advantage (from my point of view) that you can use the
TV's volume control - volume up and down are sent through the HDMI
connection.

Are you sure?

You don't need to use ARC to get that, my amp does support ARC but TV is
older and only has HDMI 1.3, so I use SP/DIF from TV to amp, and the CEC
channel lets the TV's remote control the amp's volume (once the TV's
internal speakers have been deselected) in addition turning on/off the TV
makes the amp follow suit.

On Thu, 02 Jan 2014 16:22:35 -0600, "Steve Thackery"
wrote:

Johny B Good wrote:

Once you've tried this exercise in observation, you'll be able to
better relate to the use of 'overscanning' in a modern day TV sets
when you come to google for references to this effect.

Well, I don't use overscanning. All of my viewing is in HD where
possible, and I have the TV set to pixel-to-pixel mapping at all times.

To be honest I don't notice any of the typical compression artefacts in
HD, but I do get annoyed at how "soft" they've made the pictures
(presumably to reduce the bandwidth requirements). They aren't
*really* 1920 x 1080, because the fine details smooth out at a far
larger scale than the individual pixels. They're just transmitted as
such.

To be fair, it's not a particularly noticable effect until you get
bored by the picture content and let your gaze wander off to the
edges. Once you've spotted this 'edge effect' (usually on very slow
pans with bland mid tone backgrounds), you're more likely to spot it
almost every time the picture content becomes less than attention
grabbing.

Even at its most obvious, the effect isn't a serious distraction in
dire need of removal by 'overscanning'. It's just that this seems to
be the only "good" reason for having an 'overscan' option at all.
--
Regards, J B Good

In article ,
R. Mark Clayton wrote:

This has the advantage (from my point of view) that you can use the
TV's volume control - volume up and down are sent through the HDMI
connection.

Are you sure?

Yes. That's how I do it on my Panasonic TV with Onkyo receiver. I
only use the receiver remote when I'm playing CDs - everything else
goes through the TV.

-- Richard

R. Mark Clayton wrote:

"Andy Burns" wrote:

Then you're at the mercy of whatever DAC in in the amp,

true, but if you can spot it, you must have pretty good ears.

I wouldn't claim my ears are up to it, but Jim obviously does :-P

Richard Tobin wrote:

This has the advantage (from my point of view) that you can use the
TV's volume control - volume up and down are sent through the HDMI
connection.

Are you sure?

Yes.