LFE track in ProLogic?

gmorris

Something just occured to me. When I started to build my system, I decided to buy the speakers first, then the electronics. So, I now have all my speakers, but my receiver is an old Pioneer ProLogic unit. My DVD player is connected to the receiver via left & right analog inputs. Am I missing the LFE track from DVD's? Or is it just summed into the analog outputs?

I will be getting a new receiver soon, but until I do, I'm stuck with the ProLogic representation of DVD's.


http://clubpolk.polkaudio.com/showcase/view.php?userid=49817

Dr. Spec

You're missing everything except the L/R channel from your DD or DTS DVDs.

Upgrade your AVR postehaste, and use a digital connection and set your DVD player and AVR up for digital streaming.

The Denon 3803 can be had for $650 delivered from 6th Ave and this is the AVR deal of the year and won't last.

gmorris

Maybe I didn't explain this right, I'm using the stereo L&R analog outs from the DVD (not a 5.1 output) to the stereo L&R into the Pioneer. I do get Left, Center, Right, & mixed mono surround, or ProLogic.

There is bass sound effects, such as explosions, which is why I thought maybe the LFE track is being mixed into the stereo output from the DVD.

thanks for the heads up on the Denon, I've seen it raved about here on the forum before, but I've found a honey of a deal on the Onkyo TX-SR601 for $400 from an authorized internet retailer. i like the Onkyo better than comparable units from Denon, Marantz ect.. because the Onkyo has a learning remote.

VR3

I run my system without the LFE. I run mine with speaker wire, and all a subwoofer is.....is a speaker add on. Its for speakers that cant quite cut it on the low end. So basically, R&L will give you a 20-20 signal if possible. So all low frequency action will be there, if your speakers or subwoofer can do it. It's not a matter of format. All formats are like that...unless you dont have a subwoofer and cross your stuff at like 300hz.

Gooday

- SiD

RuSsMaN

There isn't a dedicated LFE track in ProLogic, but running the l&r outs from your DVD will pass a 'full range' signal, just as if you were running a VCR, CDp, tuner whathave you.

Basically, you are running 4.1, the rears being a single channel with a bandpassed response.

Cheers,
Russ

scottvamp

Buy New Reciever
Experience Dolby Digital
Night and Day difference over analog Pro Logic
The End

Dr. Spec

Sid, all the lows will NOT be there unless you are using a DD/DTS AVR.

The LFE is a separate channel dedicated to bass. It can't be redirected to the mains unless you are using an AVR with DD/DTS decoders and a digital BM circuit.

The L/R analog outputs simply won't carry any of the other channel information to the AVR. I have a cheap DD/DTS capable DVD player hooked up to a stereo receiver in another room in a similar fashion and the LFE channel of any DD/DTS DVD is not passed on to the receiver via the analog RCA jacks.

walk

The DVD player will downmix all the channels, including the LFE, into the 2-channel analog outputs. I'm pretty sure all DVD players are required to do this, it's in the DVD spec. You might need to set this output option in the DVD player's setup.

So, you're not missing anything per-se. It's just not mixed the way it should be.

If you use ProLogic decoding you should get some center channel action and a mono, freq.-limited surround channel, but you're not getting the full 5.1/6.1 discrete full-range channels of Dolby Digital and DTS surround modes.

scottvamp

That does it - I selling all my digital recievers and going back to analog Pro Logic. Dammm, I'll just go back to VHS - screw DVD.

ohskigod

i have no problem with pro logic. i run a seperates system (instead of a reciever)

--rotel rsp 960ax preamp,
-- rotel rb-976 amp (mains and center),
--Integra adm2.1 amp for rears
--Onkyo DV-S535 DVD player
--rta 12c for mains
-- a pair of monitor 5's (as center channel)
-- Bose 501 series V rears
-- Sony sa-wd500 sub

not to toot my own horn, but this system in prologic sounds much better to me than many of the digital systems i here in the stores. I could get a dolby digital preamp, but has anyone seen the prices on those things, some are more than totl recievers. am i off base here?

gmorris

I agree with ohskigod. My setup sounds pretty good to me. I've never heard my sytem with DD or DTS, so I don't really have anything to compare it to. I'm sure when I do get the new receiver with DD & DTS, the differences will be for the good. But in the mean time, I find nothing really wrong with ProLogic.

Steve@3dai

Pro Logic II has an LFE track if I remember correctly.

But that really doesn't have anything to do with this conversation.

scottvamp

PLII is curently available on newer Digital Recievers that is why it has an LFE track.
I'm sorry but ProLogic analog and well calibrated 5.1 DD system is night and day. I jumped on the change and my jaw hit the floor. Really!!!!!!!!!!

brettw22

Aside from the DVD players that can play SACD and DVDA and have the 5.1 connections, I didn't realize that the players themselves had seperate L/R connections. How would you hook that up to a receiver that just has a DVD IN connection? Maybe I'm overthinking it.....who knows.

Dr. Spec

Originally posted by walk
The DVD player will downmix all the channels, including the LFE, into the 2-channel analog outputs. I'm pretty sure all DVD players are required to do this, it's in the DVD spec. You might need to set this output option in the DVD player's setup.

Are you absolutely sure of this? It has not been my experience thus far with the upstairs DVD player using analog RCA interconnects into a stereo receiver.

If what you are saying is true, I should be able to hear all six channels downmixed into two channels by the DVD player itself before it outputs the signal to the L/R analog jacks.

I'm going to check the set-up menu upstairs and give it a try.

HBombToo

Originally posted by Dr. Spec
Are you absolutely sure of this? It has not been my experience thus far with the upstairs DVD player using analog RCA interconnects into a stereo receiver.

I bet NO! The .1 and all other channels are HISTORY and the DPLII will only resimulate the additional channels from the 2 channel.

HBomb

Dr. Spec

Originally posted by HBombToo
I bet NO! The .1 and all other channels are HISTORY and the DPLII will only resimulate the additional channels from the 2 channel.

HBomb

I agree too. I tried to find any sort of "downmix" control and/or shutting off the digital feed to the coax and optical and I was unsuccessful.

I think all you get out the analog L/R jacks is exactly that - the L/R channels only.

scottvamp

Yep!!!!!!

walk

Mine does. I just tried it. Actually looks like it doesn't do the LFE channel, but it definitely downmixes all the L/C/R & surround channels into the 2-ch analog outputs.

So to answer the original question, looks like yes *maybe depending on your DVD player* you will be missing the LFE channel with a 2-ch ProLogic setup.

walk

It's pretty easy to see if you hook it up with the analog 2-ch outputs then use a test disc like Avia or I used the THX "Optimode" that's found on many THX discs..

Loud & Clear

Wouldn't it have to? Otherwise you'd get no dialog, or miss a lot of it, as most dialog is sent to the center speaker.

scottvamp

You guys are wayyyyy over thinking this. It will be a simple 2 channel or in prologic you will need a center. Remember center or phantom. We are not talking Digital, simple ProLogic reciever here.

gmorris

I can say without a shadow of a doubt, with my DVD player connected to my ProLogic receiver via the analog 2 channel RCA jacks, that I indeed do get Left, Center, Right & Surround channels. I said this before, I was not making it up.

I still don't know about the LFE channel. I suspect it is downmixed. I watch "Pirates of the Carribean" two weekends ago, and did hear the effect when the coin drops in the water, and the resulting ripple wave sends out a great deep, loud bass pulse. If that effect is entirely on the LFE track, then it is indeed downmixed. Or, some of the effect may bleed over into the Left & Right channels. I don't know.

I think we may have uncovered a great mystery here. But hopefully Santa Claus will bring me my Onkyo for X-mas.

scottvamp

Originally posted by gmorris
I can say without a shadow of a doubt, with my DVD player connected to my ProLogic receiver via the analog 2 channel RCA jacks, that I indeed do get Left, Center, Right & Surround channels. I said this before, I was not making it up.

I still don't know about the LFE channel
I think we may have uncovered a great mystery here. But hopefully Santa Claus will bring me my Onkyo for X-mas.

Yes, a full PL setup will be a left and right front, center and a mono low range "rear" speakers. Most early on VCR HT buffs like me ran this setup for awhile. Never a question thier.
THERE IS NO LFE TRACK ON AN ANALOG PRO LOGIC RECIEVER ON A DVD. There is NO mystery. The 2 channel track on the DVD is sent left and right analog through your PL reciever and the mixed into Pro Logic sound. It is that simple.
But with large three way speakers. 12"/15" subs and a high power Pro Logic reciever (not that common) you can put out some decent bass.
Hope you have been good enough for that Onkyo because like I said Digital and ProLogic are two different worlds.

gmorris

scottvamp,

I agree with you that the ProLogic rec. is taking the L&R signal & processing it (via ProLogic circuitry) and giving me the L,C,R & surround channels. I also agree that there is no processed LFE channel in ProLogic.

But, I also think that the DVD player is mixing in the LFE channel into the L&R analog signal. As I watch movies with a lot of bass, such as T3, I'm getting a lot of bass output. Granted, it is coming thru the L&R's (which my sub is connected to via speaker level connections) but it is still there. As I said before, maybe this is some kind of bleeding thru, or maybe the LFE channel is down mixed. This is the great mystery I was refering to.

It doesn't sound as if anyone knows for sure what happens to the LFE track in my scenario.

scottvamp

Ya, you could be right. I have seen scamatics of the mix processes of many different sounds but in your case you are going backwards in technilogy of HT sound. Like I said pro logic can produce some nice bass with the right setup.

But the LFE was designed specificly for a dedicated subwoofer in a Digital world. And that my friend what it is all about. The fact that at times on well produced 2 channel dvd's - your getting decent bass. Is nothing in comparision to a killer sub on a properly calibrated Digital HT. Were talking house shaking bass that was created for that exact frequency and part of the movie.

Dr. Spec

I have definitive scenes that prove the LFE channel is NOT downmixed on my particular POS "upstairs" DVD player using the L/R analog outputs.

The intro in Atlantis there is a humongous bass hit as the ships come over the horizon being chased by the tidal wave. It's completely absent on the L/R channels. Also, the scene in the beginning where Milo is fixing the boiler and gives it a whack with the wrench and it gives off a huge bass wallop - also completely missing.

In Harry Potter II - the fight with the Basilisk (or w/e) where it attacks him and hits its head against the rock walls - those huge bass hits are missing from the L/R outputs. Interestingly, other sections of HP II have really big bass hits in the L/R channels, so it all depends on how the DVD was mixed.

scottvamp

Originally posted by Dr. Spec
Interestingly, other sections of HP II have really big bass hits in the L/R channels, so it all depends on how the DVD was mixed.

Exactly, depends on just how the 2 channel mix on the DVD was produced. No LFE is blended in. No surround is blended. Also a huge difference is center channel signal by the PL reciever only produced dialoge - well on VHS anyway. Digital it is 70% of the front stage. Huge difference Gmorris...
Thanks DOC*

RuSsMaN

Straight from Dolby labs:

"If you are playing DVDs through a two-channel stereo TV set or audio system, or an older home theater system that provides only Dolby® Surround Pro Logic® decoding (and not Dolby Digital), you should connect the player’s analog stereo output to a spare stereo input on the playback system. The two-channel Dolby Digital decoder built into the player will “downmix” 5.1-channel Dolby Digital programming, such as movie soundtracks, to Dolby Surround-encoded analog stereo."


Link

End of **** discussion. You have the DD 5.1 info downmixed into a 2ch Dolby Surround encoded stereo signal, which is passed to the Prologic decoder in the receiver.

Jesus H Christ.

Cheers,
Russ

scottvamp

WOW!!!!!:eek:
Thanks for Hijacking our thread and basicly telling us to shut the **** the up!!!
Nice little too much eggnog buddy.
We were have a




wait for






wait for it





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nice discussion.

We were explaining this concept there buddy.



And if you want to get even more technical.
You can have to totally different ProLogic sounds.
1)From an old school analog ProLogic reciever
2)From a Dolby Digital reciever with ProLogic processing.
Figure that one out....
Oh wait we are not allowed to discuss things here.....
PS.... We know it is dowmixed into 2 channel but the discussion was more to how it was downmixed and then reprocessed to pro logic.
Dam, let me just shut the **** up

RuSsMaN

Get over yourself already. What was the original question, and who was the 4th person to participate in 'this discussion'?

I've done nothing short of provide accurate information, I don't qualify that as hijack, anymore than what you've had to add here.

Carry on ladies!

Cheers,
Russ