Couple simple 921 ?'s

[tlturbo]

OK, this is probably elementary stuff for most of you, BUT as a new HD 921 owner (had a 501) I have a few questions.

The BLUE light on the front of the receiver LIT BY ITSELF means HD - but it appears that there is HD then there is REAL HD. Can someone explain why some HD doesn't really look like HD? (YES, I have a 65 Mitsu HD TV) Is that because it is being broadcast in HD but was NOT RECORDED in HD so it really isn't true HD but because it is being broadcast in HD, the blue light is on. WHEW!!!

Also, what is the best audio that satellite channels are broadcasting in? Am I right in understanding that Dolby Digital 5.1 IS NOT available on any satellite channels? If so, what is sent? I have a blue bar on my A/V receiver that is lit when something is Dolby Digital and it is lit lots of the time. So what am I receiving?

Thanks for the education - Terry

 

[reedl]

On the 921, the Blue light always light whenever the HD outputs (component, and DVI) are active. It does not matter what the input or source signal is, just that those outputs are active. So you could be watching SD programming even thought the Blue lights are on. Think of the light as which output is active.

As to audio, most of the standard programming is just PCM stereo which should not light your light on the stereo. OTOH, all of the terrestrial digital stuff, some premium movie channels, and the HD programming is all broadcast in Dolby Digital (AC3) format. Now that format might be 2.0 (left and right only), or 5.1(Left, center, right, left surround, right surround, and subwoofer (the .1) ) Some stereos always show dolby digital even though the signal is 2.0. There might be a way on your unit to acually see what the format coming in is.

HBO, SHO, Starz, and a few other premium movie channels are broadcast in both PCM stereo and Dolby Digital. The HD programming (DiscoveryHD, HDNET, HBOHD, SHOHD) are pretty much always 5.1, but some stuff is 2.0 It all depends on the origional source of the material..

Reedl

 

[A_Noland]

moving to the 921 forum.

 

[SimpleSimon]

The BLUE light on the front of the receiver LIT BY ITSELF means HD - but it appears that there is HD then there is REAL HD. Can someone explain why some HD doesn't really look like HD? (YES, I have a 65 Mitsu HD TV) Is that because it is being broadcast in HD but was NOT RECORDED in HD so it really isn't true HD but because it is being broadcast in HD, the blue light is on. WHEW!!!

Yes, what reedl said. Blue/Yellow light tells you which output is active, has nothing to do with the content. Either type can go out of the 921 as either HD or SD - the box handles up/down converting as needed (although it doesn't do a great job of it - software fixes coming).

Also, what is the best audio that satellite channels are broadcasting in? Am I right in understanding that Dolby Digital 5.1 IS NOT available on any satellite channels? If so, what is sent? I have a blue bar on my A/V receiver that is lit when something is Dolby Digital and it is lit lots of the time. So what am I receiving?

Yes, what reedl said, except I get a lot of the channels in PCM 48. I'm set for both types of output and use a digital connection to my Sony STR-DE695. It tells me the audio type on it's front panel. I have found that some of the DD 5.1 audio stinks - the studio audio people do a lousy job of mixing the surround channels. In a lot of cases, I've gotten better results by letting my stereo do it's synthesis thing off of 2 channel (usually PCM) inputs. It's really amazing what it can do. With 2-channel input, I've heard it 'extend' a car driving across screen all the way to the appropriate surround speaker. Other sound effects are 'extended', too. It does a great job of enhancing audio CDs, too. I've got no idea what's in that box but it's smarter than I am.

 

[reedl]

As to 2 channel audio compared to 5.1 audio, and 5.1 always being better, you are very correct that sometime the 5.1 audio is just plain bad. For example the SuperBowl on CBS had very bad 5.1 audio, but the stereo was pretty good.

The way your stereo takes two channels and converts it to four is by using the following rules:

1) Everything in just the left goes to the Left.
2) Everything in just the right goes to the right.
3) Everything that is completely common to both left and right and is in phase is removed from the left and right, and moved to the center channel.
4) Everything that is completely common to the left and right but is 180 degrees out of phase (kind of like hooking up stereo speakers with one hot and ground reversed),
is sent to the rear speakers.

This is called Dolby Pro-logic, and has been around for years. Now I think that the stereos or today have more intelligence in that audio that is somewhat between the left and the new generated center will result in the audio coming out of both the left and center speaker. This gives a more complete soundstage on cars traveling across the screen for example. If you have access to something that will generate stereo tones you can hear the soundstage move around the room in Pro-Logic Mode. Pro-Logic II is just simply better Pro-logic processing, and I think it somehow simulates two rear speakers.

5.1 audio on the other hand sends individual channels of audio to the left, center, right, left rear, and right rear. What goes to the center channel is what the program provider says goes to it, and nothing more. Anything more the stereo generates (for example my Yamaha RX-V1 in my theater generates a rear center much like the front center is generated in Dolby Pro-Logic) is exclusive to that unit, but is not coming "down the pipe". My RX-V1 also generates two "effects" channels that when the unit is put into enhanced DD mode, add fullness to the audio (making it sound more like a real theater).

Sometimes the people who mix 5.1 stuff (usually on live stuff BTW) do the best they can, but they can never get it perfect when live, unlike movies where they have lots of time to do it. Also some pre-produced stuff is pretty bad. I have heard 5.1 mixes that were basically garbage. For general TV viewing, sometime 2.0 is much better to use.

Reedl

 

[tlturbo]

Thanks for all the knowledge guys.

Terry