Dolby Pro Logic Surround

Boggles

Greetings

I want to buy a new CRT television, have stuck with Sony & Mitsubishi in the past. I'm just a little confused what the difference is between actual "Dolby Pro Logic Surround" and "Dolby Virtual Surround", and various other trade mark audio technology now that is written into the specifications.

I have looked at a good few newer models of crt's online and none of them seem to come with what I consider good old fashioned surround sound, meaning 2 external satellite speakers placed behind you and 2 or 3 speakers stuck in the telly.

Would be grateful if anyone could clear this up for me and stear me in the direction of proper surround sound crt's. Thanks in advance.

Sparky

the virtual surround is where it gives the listener a feeling of surround sound without 2 rear speakers.

Ive heard a sony with this and was impressed with it as i assumed it would be crap, but its no replacement for actually having 2 rear speakers.

It also depends on the placment of the tv aswell

Boggles

Yeah thought that is what it might be alright, do you know if they have scraped the notion of the 2 rear speakers in favour of seperate external surround sound systems?

Clank

Ive never heard of CRT tvs coming with 2 rear surrounds.

Anywho, Dolby Surround is a built in feature of a lot of modern tvs, it basically tries to bounce the sound off the walls to create the surround effect, sounds crap though.(IMO)

Dolby Pro Logic is a system where your amplifier receives a stereo signal and spits it out in 5.1, it is never built into tvs(as it requires 6 speakers)

--Both are pseudo surround, not true 5.1.

What id recommend is buy your CRT based on picture quality alone(speakers on my CRT havent ever been used) and buy a surround sound setup separately.

Boggles

Clank wrote:

Ive never heard of CRT tvs coming with 2 rear surrounds.

Dolby Pro Logic is a system where your amplifier receives a stereo signal and spits it out in 5.1, it is never built into tvs(as it requires 6 speakers)

Thanks for the reply mate. It has been built into TV’s alright; I have 2 of them in my house.

5.1 is in fact 6 speakers but the '.1' donates the sub woofer and is called this because it only carries 1/10 the bandwidth of any of the other 5 channels. It grabs all the low frequencies and churns it out as bass.

I have tried these home theatres before and have never been comfortable with the quality of the audio when watching terrestrial channels and sky. I have a Sony dav-s300 which I use watching DVD’s and have yet to come across a better system for audio, but if I pump terrestrial and sky through these it just doesn't sound right, overkills the audio. Plus with these home theatres it is another thing to run everything through and another device that needs to be switched on.

ShiverinEskimo

If your worried about having to run cables and switch another thing you don't seem too enthusiastic about getting high-quality sound from what you watch.

I run all my audio through my Onkyo receiver and surround speakers and even last night the champions league pumped up loud and dobly pro-logic'ed through my floor standers is far better than anything my TV with its "Virtual Surround" speakers can produce.

Do yourself a favour - save up and invest in a decent receiver and speakers.

Ivan E

Just to clear something up here but there is a slight mix up between Dolby Pro-Logic and Dolby Digital 5.1 here. Dolby Pro-Logic I believe does not use the subwoofer and uses both rear speakers as one i.e sound comes from both speakers with no differentiation. Dolby Digital on the other hand uses the rear speakers separately where they work individually.

DOLBY PRO-LOGIC
Dolby Pro-Logic is analog system that appeared in consumer products in the fall of 1987. It takes the two-channel analog signal and separates it into 4 channels (and adds delay to the rear channels; the amount of delay sometimes can be adjusted):
1. Center Channel
2. Left Channel
3. Right Channel
4. Rear Channel (the same signal is directed to 2 rear speakers)


DOLBY DIGITAL 5.1
In Dolby Digital 5.1 the digital signals for 6 channels are transferred from DVD player to the Dolby Digital Decoder through either coaxial or optical input:
1. Left Channel
2. Right Channel
3. Center Channel
4. Left Rear Channel
5. Right Rear Channel
6. Subwoofer

Boggles

ShiverinEskimo wrote:

If your worried about having to run cables and switch another thing you don't seem too enthusiastic about getting high-quality sound from what you watch.

I run all my audio through my Onkyo receiver and surround speakers and even last night the champions league pumped up loud and dobly pro-logic'ed through my floor standers is far better than anything my TV with its "Virtual Surround" speakers can produce.

Do yourself a favour - save up and invest in a decent receiver and speakers.

I have a decent receiver, the sony dav-s300. Which is perfect for watching DVD's, but overkill for everything else, When watching the news I don't really want to hear Charlie Bird screaming his head off in bone crunching 5.1.

Never heard of Onkyo, but will look them up if I'm forced down that route.

So no one knows if any of the new TV's coming out with lets call it "diet dolby" not the newer virtual dolby.

Boggles

Ivan E wrote:

Just to clear something up here but there is a slight mix up between Dolby Pro-Logic and Dolby Digital 5.1 here. Dolby Pro-Logic I believe does not use the subwoofer and uses both rear speakers as one i.e sound comes from both speakers with no differentiation. Dolby Digital on the other hand uses the rear speakers separately where they work individually.

DOLBY PRO-LOGIC
Dolby Pro-Logic is analog system that appeared in consumer products in the fall of 1987. It takes the two-channel analog signal and separates it into 4 channels (and adds delay to the rear channels; the amount of delay sometimes can be adjusted):
1. Center Channel
2. Left Channel
3. Right Channel
4. Rear Channel (the same signal is directed to 2 rear speakers)

That's exactly it, fair play to you.

Calibos

Correct for original Pro logic but not for Prologic II or IIx. Prologic II delivers a full 5.1 experience. TBH you'd be hard pressed to buy any new surround gear that didn't have the newer versions of ProLogic.

ProLogic II was a revelation to me when I upgraded amps. Whereas with my old amp and original prologic sound better then vanilla stereo obviously it wasn't a patch on Dolby Digital 5.1. The only way to describe what the rears sounded like was that you would know they were on but you couldn't particularily say what the sound was. It just kind of changed the ambience. Kinda like sitting in a silent room sounds different to sitting in the middle of a silent field. No sound either place and yet one 'Sounds' different to the other. Thats the best way I can describe it.

Anyway ProLogic II sounds infinitely more DD 5.1 like. you can actually hear distinct sounds behind and to the left or right of you.

So whats the difference between Dolby Digital and ProLogic II then?? Well with DD 5.1 the sound engineer places the sounds exactly where he wants them in the sound field. With Prologic II its the electronics in the actual amp that take the ProLogic II encoded stereo signal and makes a best guess as to where the sound should go within the sound field and its usually not far off. ProLogic IIx on the latest kit makes a better guess again.

Don't get me wrong DD5.1/6.1 does sound a lot better but the gap between watching a television show and a DVD doesn't sound anywhere near as dramatic as it used to before ProLogic II.

Put it this way my upgrade from a DD5.1/Prologic amp to a DD6.1/ProLogic II amp wouldn't have been worth it for 5.1-6.1 It wouldn't have been worth it for extra novelty DSP modes. It wouldn't have been worth it for the extra 20watts per channel power. It was worth it for getting ProLogic II alone never mind the other bonuses.

ShiverinEskimo

Boggles wrote:

I have a decent receiver, the sony dav-s300. Which is perfect for watching DVD's, but overkill for everything else, When watching the news I don't really want to hear Charlie Bird screaming his head off in bone crunching 5.1.

Fair enough - within reason. Champions League bernabeu style isn't exactly comparable to the sixone news. :rolleyes:

But watching a movie on tv coming down in stereo sounds much better via the receiver's Pro Logic II or DTS Neo 6 settings than from my tv's virtual surround speakers. Never mind watching a DVD in DD:EX or DTS:ES...

Calibos

Should have read the thread properly. Seems like boggles has a surround system already but he doesn't like the bone crunching dav300 5.1 when watching the news but doesn't want to watch the news in vanilla Stereo either. You want a prologic 2 capable CRT to watch the news??

Why don't you just turn the dav volume down so its not bone crunching then??

Boggles

Calibos wrote:

Should have read the thread properly. Seems like boggles has a surround system already but he doesn't like the bone crunching dav300 5.1 when watching the news but doesn't want to watch the news in vanilla Stereo either. You want a prologic 2 capable CRT to watch the news??

Why don't you just turn the dav volume down so its not bone crunching then??

I'll clarify, it's for the second telly that is fed by rf cable.

Plus I'm getting old and I don't like change. )