HTPC audio into plasma/lcd

[frankmcg]

Just a quick question, but 20mins wasted on google didn't throw up an answer!

About to buy myself a new plasma screen and noticed the audio inputs are only on the front of the set. Without using an amp, and assuming I'm connecting via a DVI->HTMI cable, does that carry the audio too ie I don't need separate audio leads? The specification implies that it does but it seems unlikely to me! Currently I have a scart to s-vid/audio converted plugged into my CRT and then everything connects into that.

If it doesn't, what are people using as their solution, since I'm assuming everyone with an LCD/plasma screen is connecting via VGA or DVI/HTMI? Does everyone apart from me have a separate amp?!

[nitrogen_widget]

you will have to check the manufacturers specs on this but as a general rule the HDMI cable carries the sound & video.

that is how it is with the 3 HDTV's I have seen anyways.

I would look for a TV with a VGA connector then you can use one of the audio inputs.

[groover km]

HDMI carries video and audio, DVI carries video only. If you are connecting via DVI (at either end), you will need some form of audio hookup.

Are you sure the only audio inputs available are on the front? That is very surprising; I would expect to find at least RCA inputs, quite possibly digital too...

[frankmcg]

My bad. You're quite right it does have audio inputs on the back panel, although it took me to download the user manual to find that out.

I'll blame the misleading specification page on the manufacturers' website rather than my stupidity though!

[groover km]

Glad you got it solved; I love it when I can download a product manual before a purchase. It's saved me from mistakes in the past.

Don't forget to share with us your choice and experience when you get your new tv!

[frankmcg]

Well got my new TV delivered yesterday and just had a couple of hours to play about with it. It’s a 42” Panasonic (TH42TX60) UK model with built in digital tuner.

All good so far in terms of setting up using a DVI-HDMI cable and no problems with the audio-in in reference to my original post. GB-PVR working great on it and picture nice and crisp even on the “running in” settings recommended for the first 200 hours.

Only headache so far is in relation to correct resolution to use. MCE reckoned I should use 1280x720 as a proper HDMI compatible resolution, but the panel’s native resolution is 1024x768, which obviously isn’t a 16:9 AR but the screen has non-square pixels. It seems to be a common problem with the 42” screens that there isn’t 1 correct resolution to use.

To summarise the debate on this as far as I understand it:

If you want to use a DVI-HDMI cable you need to use 720p res. as it doesn’t support 1024x768. This makes the desktop look quite fuzzy (not an issue for me as this is a dedicated HTPC) but is the correct AR. It also can have issues with playing 50hz material (haven’t noticed this).

If you use a VGA cable on the other hand, you can have a 1024x768 res and select 50hz or 60hz refresh. This makes the desktop look correct but stretches or squashes (not sure which as I haven’t tried this) films unless you force the player, GB-PVR in this case!, to the correct AR. I guess this would be done by telling GB-PVR that it’s running on a 4:3 screen but I haven’t bothered to try this yet as am I’m happy with the DVI method. In theory doing all of this gives a sharper picture as there is less scaling going on!

Sorry for the long post but I thought this might be of interest to some.

[madcat]

If you want to use a DVI-HDMI cable you need to use 720p res. as it doesn’t support 1024x768. This makes the desktop look quite fuzzy (not an issue for me as this is a dedicated HTPC) but is the correct AR. It also can have issues with playing 50hz material (haven’t noticed this).

If you use a VGA cable on the other hand, you can have a 1024x768 res and select 50hz or 60hz refresh. This makes the desktop look correct but stretches or squashes (not sure which as I haven’t tried this) films unless you force the player, GB-PVR in this case!, to the correct AR. I guess this would be done by telling GB-PVR that it’s running on a 4:3 screen but I haven’t bothered to try this yet as am I’m happy with the DVI method. In theory doing all of this gives a sharper picture as there is less scaling going on!

Sorry for the long post but I thought this might be of interest to some.

All sounds correct (and BTW, another reason why I went for the 50" league, as they have real 16:9 native res.).

However, one thing I didn't quite get - why would anything (desktop, movies, etc.) behave differently when using the same resolution (i.e. 1024x768) over different cables (dvi/hdmi vs. VGA)? I would imagined if you send this resolution over those two different cables, the result would be quite identical (except for maybe "crispness", as the DVI/HDMI is digital, vs. the Analog of the VGA cable, or for the options the TV would present you with, as to "stretching", "zoom", etc.).

[sub]

GB-PVR ignores the resolution entirely, so this shouldnt be a problem, instead doing stuff based on the tv shape setting in the config app.