PL2 question

[Mr Peabody]

Hi;

I finally have some new technology. The processor I have, Primare SP31.7, has Pro Logic 2, actually 3 versions, normal, cinema and music. I thought PL2 created a simulated Dolby Digital signal from 2 channel or old Pro Logic. I notice so far when listening to videos or satelite and using PL2 that there doesn't seem to be anything coming from the sub. The question I have, does PL2 provide a LFE signal?

[Lexmark3200]

Hi;

I finally have some new technology. The processor I have, Primare SP31.7, has Pro Logic 2, actually 3 versions, normal, cinema and music. I thought PL2 created a simulated Dolby Digital signal from 2 channel or old Pro Logic. I notice so far when listening to videos or satelite and using PL2 that there doesn't seem to be anything coming from the sub. The question I have, does PL2 provide a LFE signal?

Funny you should post this; I watched "Independence Day" last night on VHS (the original store-bought VHS tape with the THX certification) and ran it through my receiver's Pro Logic II Movie mode and noticed no bass as well....no VHS tape I run through Pro Logic II has any LFE signal it seems, although I read that Pro Logic II is supposed to SIMULATE 5.1 Dolby Digital and such, with BASS MANAGMENT added for some low frequency effects....I find none of this happening when watching VHS films.

[himanshu]

Read this -

http://www.hometheaterhifi.com/volum...ix-3-2004.html

PLII is a 5.0 "decoding" and hence nothing comes from your sub. Please remember in DD and DTS there is a LFE channel encoded in the source material, which is what comes out of your sub. In DD 2.0 or any other stereo material, there is nothing encoded for LFE and PL2 merely simulates enveloping the sound by splitting some of 2.0 sound into surround speakers and center speaker. LFE doesn't come into picture at all.

[Lexmark3200]

Read this -

http://www.hometheaterhifi.com/volum...ix-3-2004.html

PLII is a 5.0 "decoding" and hence nothing comes from your sub. Please remember in DD and DTS there is a LFE channel encoded in the source material, which is what comes out of your sub. In DD 2.0 or any other stereo material, there is nothing encoded for LFE and PL2 merely simulates enveloping the sound by splitting some of 2.0 sound into surround speakers and center speaker. LFE doesn't come into picture at all.

While Im going to believe what you are saying above, EVERY magazine review of A/V receivers, including Crutchfield, claims PRO LOGIC II turns "STEREO MUSIC AND STEREO SOURCES INTO 5.1 AUDIO"----NOT 5.0. Read descriptions of receiver models in magazines and see what they say. They all claim PL II creates 5.1 sound from stereo sources.

[vivisimonvi]

Let's clarify a few things. First of all, TRUE 5.1 audio is another way of saying there are 6 SEPERATELY recorded audio channels from a given source (right, left, center, rear-right, rear-left, and a bass signal)... what makes the .1 (or LFE) special is that it is it's OWN channel, for bass (it's not just a bass channel but a channel especially mixed by the soundtrack's audio engineer, the same goes for the other 5 channels)... 5.1 is commonly reffered to Dolby Digital or DTS (or some other MULTIchannel soundtrack)... In other words, the entire soundtrack is already recorded in 6 audio channels, when listening to DD or DTS, you hear EXACTLY what was recorded... It just so happens that most LFE recorded material sound a lot better with bass (being that it is a seperate channel it's no suprise for this reasoning). What's even better is that you can reroute the LFE signal from your other speakers to your subwoofer (provided it has it's own amplifier) to add less stress on your receiver (hence the .1 meaning it requires 1/10 of power from your receiver in doing this).

All other "5.1 sound modes" (PL, PL2, NEO6) you will get is a simulated version no matter what 2 channel source you throw at it... Any receiver's attempt to parse a 2 channel signal into 6 seperate ones will not come close technically to the mastery of a true 6 seperate channel audio signal. While it's true you can hear a bass signal from your mains, or your subwoofer when listening to these soundfields, it's a quite different from hearing it from 6 seperate channels or real '5.1'...

From the magazine's point of view, they aren't wrong in saying PL2 creates 5.1 audio (it's good marketing for them, like any magazine)... PL2 can make any 2 channel source come out of 6 speakers is what they are really saying (to make matters seem even more spun around they can call it 5 with the point one since any DD receiver is capable to cutting off the low frequencies and routing them to a seperate powered amp or sub, or just cutting them off altogether)... but the problem here is that you aren't hearing 6 discreet channels each specifically recorded from the source.

[vivisimonvi]

Funny you should post this; I watched "Independence Day" last night on VHS (the original store-bought VHS tape with the THX certification) and ran it through my receiver's Pro Logic II Movie mode and noticed no bass as well....no VHS tape I run through Pro Logic II has any LFE signal it seems, although I read that Pro Logic II is supposed to SIMULATE 5.1 Dolby Digital and such, with BASS MANAGMENT added for some low frequency effects....I find none of this happening when watching VHS films.

Were you watching this movie in Hi-Fi? It makes a hellva much difference listening from normal stereo and Hi-Fi, anyone will agree with me on this one... This used to be my favorite "blast effect" movie, as I wouldn't watch it without a Hi-Fi capable VCR... I just got it on DVD this week, I have yet to experience the Dolby Digital version.

[Lexmark3200]

Were you watching this movie in Hi-Fi? It makes a hellva much difference listening from normal stereo and Hi-Fi, anyone will agree with me on this one... This used to be my favorite "blast effect" movie, as I wouldn't watch it without a Hi-Fi capable VCR... I just got it on DVD this week, I have yet to experience the Dolby Digital version.

Yes, of course....it was the original store-bought VHS tape in Dolby Hi Fi Surround and THX certification.

[wasch_24]

Yes, of course....it was the original store-bought VHS tape in Dolby Hi Fi Surround and THX certification.

Of course the VHS was HiFi but vivisimonvi was asking if the VCR was set to HiFi. Some VCR won't automatically pick up the fact that the tape is HiFi. You might have to set it in the setup menu.

[Lexmark3200]

Of course the VHS was HiFi but vivisimonvi was asking if the VCR was set to HiFi. Some VCR won't automatically pick up the fact that the tape is HiFi. You might have to set it in the setup menu.

The display on the VCR screen lights up red and reads "STEREO" automatically when a stereo tape is dropped in.......

[Mr Peabody]

Good article and an interesting website I plan to check out more. The article gave good information without losing you with too much technical talk. Thanks

[Lexmark3200]

Good article and an interesting website I plan to check out more. The article gave good information without losing you with too much technical talk. Thanks

Interesting website and article? Which was that?

[wasch_24]

Interesting website and article? Which was that?

Post number three (#3)

[Lexmark3200]

Post number three (#3)

Ahhhhh.....okay.

[46minaudio]

Hi;

I finally have some new technology. The processor I have, Primare SP31.7, has Pro Logic 2, actually 3 versions, normal, cinema and music. I thought PL2 created a simulated Dolby Digital signal from 2 channel or old Pro Logic. I notice so far when listening to videos or satelite and using PL2 that there doesn't seem to be anything coming from the sub. The question I have, does PL2 provide a LFE signal?

How new my $650 Yamaha has DPL2x...Applys DD 5.1 to 7.1...