What sound mode is best for watching TV/VHS? (1 Viewer)

[elatia_g]

I just bought a Sony receiver which is capable of 5.1 ch sound and still know next to nothing about it. When watching a regular TV broadcast or a VHS video, is it best to watch in 5.1 ch mode or AFD mode, which is front spkrs and subwoofer only? I tried watching TV in the 5.1 ch mode, which is called normal surround, but sound only came out my ctr spkr. However when I listen to radio in that mode, I get sound out of all the spkrs. If they're both 2 ch formats, why the difference? Thx for any info. :b

 

[Marc Rochkind]

Not being familiar in detail with this particular receiver, could you be a bit more specific?

When you say "5.1 mode" do you mean Dolby Digital, Pro Logic, or Pro Logic II?

If DD, there is no DD encoding on VHS (no room). Most people watch tapes in Pro Logic (or Pro Logic II), which is more or less OK even if there isn't a specific Dolby Surround encoding on the source.

As to why you are seemingly getting 5.1 from radio sources, I haven't a clue.

Hope this helps... sorry if I misunderstood your question.

 

[elatia_g]

What I mean is I have it set to normal surround which is Pro Logic and uses all 5.1 spkrs. I get sound out of all the spkrs listening to the radio, but only from the ctr ch when watching TV. I was wondering if Pro Logic is a good mode to watch VHS tapes in, or should I stick to AFD which is right front and left front spk + subwoofer. TIA.

 

[Robb W]

I also have a Sony reciever. If I remember right AFD is Auto Format Decoding. When a Pro Logic signal is available from TV it automatically switches to Pro Logic. If no signal is detected it automatically defaults to the 2 front channel speakers and subwoofer.
You are correct when you say the Normal Surround Mode is Pro Logic. I'm pretty sure you can't consider it 5.1 though since in Pro Logic the back to speakers output the same sound, vs watching a DVD which is true 5.1 (ie - All five speakers are capable of outputing a differnt sound). As far as what to watch VHS in I prefer Pro Logic (Normal Surround) for both TV and VHS. I prefer the sound to come out of my center channel speaker when watching a non-Pro Logic TV show vs. having the sound come from the two front channels. It pretty much comes down to what you prefer.
When you listen to the radio in Normal Surround the reciever sends the same signal to all 5 speakers, which is something that most receivers do if I'm correct. Again, it's not true 5.1 sound because all of the speakers are recieving the same signal.
Hopefully this makes sense...

 

[Jeff Kleist]

Make sure your VHS deck is reading the Hi-Fi Stereo track. A VHS tape has 2 tracks, normal and Hi-Fi. Stereo is only available on Hi-Fi

 

[Mark Hobbs]

We don't use VHS, but we watch TV in Dolby Pro-logic II and enjoy it. Some shows only send sound to the center channel, but most (of the ones we watch anyway) are encoded for surround. Movies sound great using DPL II.

We have a Denon 1802 receiver.

 

[elatia_g]

Well when I watch TV in the Pro Logic it sends sound only to the ctr ch. Is it supposed to do this? If I put it to AFD where only the mains and subwoofer are used, then it sounds OK. So now I only watch DVDs in full surround and with VHS, I must still experiment. I'll keep my faithful VCR until DVD recorders become cheap and reliable. Then there's a matter of this copyright BS. If the ent industry and govt get their way, we might not even be able to use DVD recorders the way we presently use our VCRs.

 

[Jeff Kleist]

Your local TV station or (more likely) cable system may only be carrying a mono signal as well, to save bandwidth.

 

[elatia_g]

Maybe. If I watch it in AFD mode, then I get good stereo sound. A friend suggested hooking the TV up thur the aux input instead of the TV input. He says he has his hooked up that way and it works with the Pro Logic, so I'll try this and see if it helps.

 

[Harold_C]

Dolby Pro Logic (or Pro Logic II) is the standard decoder for Dolby Surround matrix encoded stereo material. Dolby Surround stereo recordings are standard two-channel recordings that have center and mono surround channel information "matrixed" or "encoded" into the left and right channels. The Pro Logic decoder uses "phase" information in the recording to extract the center channel and surround channel signals.

This Dolby Surround/ProLogic decoding is pretty much the best that you can do with a two-channel analog recording (VHS, analog, TV sound, radio broadcasts, etc.) and has been the standard in the movie industry since the 1970s. Dolby Pro Logic decoding is specifically intended to decode Dolby Surround recordings, however it will also work with ANY stereo recording -- to varying (and largely unpredictable) degrees.

For your VHS tapes, Dolby ProLogic is definitely the surround mode to use. The vast majority of pre-recorded VHS tapes are Dolby Surround encoded and, even if you find one that is not, Dolby Pro Logic is still a good choice.

Dolby ProLogic is also an OK choice for your FM tuner. This is a stereo signal, so Dolby Pro Logic should generally be able to extract a little ambience for the rear channels and extract a center channel signal. (The same thing applies to using Pro Logic for a CD.) I find that Pro Logic does OK for this, with my only complaint being that it tends to put a little too much signal in the center channel. Your only alternatives are straight 2-channel stereo (no surrounds, no center) or the various DSP modes (cathedral, stadium, etc.) which tend to be rather ghastly.

Dolby ProLogic is also a good choice for general purpose TV watching. It works great with shows that are actually broadcast in Dolby Surround. It works pretty well with shows that are actually recorded in stereo (see FM tuner above). However, many shows are essentially broadcast with a mono soundtrack (they may be technically broadcast "in stereo" but there is no stereo separation). This is most noticeable on old TV shows (from the pre stereo days) and on news broadcasts. In these cases, Pro Logic is going to do just what it is supposed to do and put the mono information in the center channel. Therefore, it is very common to hear just center channel on a TV show with Pro Logic decoding. The only alternative would be one of the DSP modes, which will synthesize "something" for all five speakers, although whether that "something" sounds good is for you to decide.

Far and away the best surround sound performance will come from Dolby Digital or DTS 5.1 channel recordings. However, these are ONLY available from a digital source, so most likely they will only be available from your DVD player. To get Dolby Digital, you MUST have your DVD player connected to your receiver with a digital cable (coax or optical). And, in many cases, you must select the Dolby Digital 5.1 soundtrack from the start up menus when you insert the DVD disc in the player. If you don't have the digital cable or if you don't select the DD 5.1 soundtrack, the Dolby Digital light won't light up on your receiver and you will be listening to a matrix stereo version of the DVD soundtrack with Pro Logic decoding -- the digital version of a VHS tape.

Hope this helps.

 

[Harold_C]

A friend suggested hooking the TV up thur the aux input instead of the TV input. He says he has his hooked up that way and it works with the Pro Logic, so I'll try this and see if it helps.

That will not make any difference at all. There is no difference between the TV inputs and the AUX inputs, except for the printing next to them on the back panel.

 

[elatia_g]

That's just so. No difference, so I changed it back. Maybe it's cause he has a different TV from mine. But it works fine in AFD mode. TV broadcasts aren't meant to be heard in all 5.1 ch anyway. However radio broadcasts sound great.

 

[elatia_g]

And yes I do have DVD player and amp hooked up thru the optical so I do get true Dolby Digital and DTS sound. It rules!

 

[Jeff Pryor]

Say it again, brother! DTS!

If a TV broadcast is in stereo or surround, my DD (pro-logic when it detects analog signals) decoder works great. If the broadcast is mono then the decoder automatically sends it through the center channel only. This is completely normal. I've noticed I get better sound using the Dolby circuit instead of the AFD.

 

[elatia_g]

I only get better sound with Dolby when it's DVD or radio. If the TV broadcasts are mono and get sent to the ctr ch in Dolby, why do they sound like they're stereo in AFD? I hear discrete sounds in the right and left channels? I'm totally confused now. :frowning:

 

[Harold_C]

TV broadcasts aren't meant to be heard in all 5.1 ch anyway

Actually, quite a bit of network TV is recorded in Dolby Surround and is intended to be played back with Dolby Pro Logic decoding. However, it varies. Prime time shows are most likely to be recorded in Dolby Surround. Big budget ads are often broadcast in Dolby Surround as well.

You do have to make sure that you are actually receiving a stereo signal on your TV. You should be able to tell from something like VH1.