I'll take a crack at this:

1) add audio track. As long as it's routed to the master bus, just double click on the surround panner and click on the icon in the upper right to switch to LFE
2) all audio on that track passes through a low pass filter (selectable in prefs)

3) when you add busses to a project, you can route tracks to the bus by clicking on the Maze looking square icon in the track header. This will give you choices between master and busses. If you route to a bus, you control panning from the Bus Surround Panner window.

as for the different pan options, those control the attenuation (if any) of the signal when you pan it towards different channels to compensate for "mono-ness". If you have a mono track to pan hard left or right, you'd want to the option to reduce gain by -6dB so it won't clip when you pan it. I think Constant power does that too. That should be in the online help.

hope this helps.

Thanks, but let me get point 1 straight.
If the audio track I want to assign to LFE is a music track, what happens to the higher frequencies?
Should I copy the entire track to a new track and assign one of the identical tracks to LFE so I have two similar tracks but one going to the sub woofer the other track to the normal front and rear speakers?

Thanks once more.

Add to all of that this mixing guidlines PDF from Dolby:

Dobly Mixing Guidelines

Aha, finaly a manual.
I will study it carefully.

Thanks, Dries.

It deals with audio 5.1 production, mostly technical aspects.

Go here for a bunch of PDFs on all relevant topics:
http://www.dolby.com/digital/

The simplest way to build LFE content from a single track while still sending the 5 channels to the master is to add a Sub bus to the mixer.

Set the sub bus to handle only LFE by setting the Surround panner on that bus to LFE only (Right click on it)

Then, on the track of audio, click on the pan controller to the far left and expose the Bus A send. Increase this gain until you get the mix you want.

You can even add an FX to Bus if you want to really push the bass into the LFE channel.

Peter

> Question 2: If 1 works out, does this mean that low frequency is filtered form all the other tracks as checked in audio pproperties?

Just to be clear about what you're asking: If you use an LFE, are the low frequencies filtered OUT from the other tracks? If so, no. In fact, this is one of the reasons NOT to use an LFE. If you just routed your audio normally to the 5 channels, the bass from all these channels will also be routed to your sub-woofer, and it will sound fine. IOW, you can ignore the LFE entirely, and should in most cases. Routing the same information to both your subwoofer (indirectly) and the LFE can actually cause sound cancellation and make it worse. The purpose of the LFE is not to route your bass to your subwoofer, its to route *special* bass to a set of special bass speakers that the movie theater may have. There are some comments in the dolby links that were provided. Copied from another thread where I found this out:

----------------
From the source: dolby article

"Keep in mind that Dolby Digital's five main channels (L, C, R, LS, RS) are all full-range, and the LFE channel does not extend frequency response. It exists primarily to enable more powerful low-frequency special effects for film soundtracks. Also, remember that all Dolby Digital decoders offer bass management, a feature that enables the consumer to direct extreme low frequencies to a subwoofer , or to any of the speakers in the system (such as L and R) that can reproduce low bass. When bass management is used, a ".1" track derived from a four or five-channel mix may cause unwanted summing or cancellation of low frequencies in a subwoofer. Delivering a quality track with five full range main channels, which allows the end user to optimise bass management to his specific playback system, is the best way to assure accurate delivery of the sound intended by the program's producers."

IOW, leave that LFE channel empty unless you're making Earthquake.
-------------------

RichMacDonald: That's the impression I'm getting from looking at Dolby documents. Yet you hear all the time about how in 5.1 the ".1" is the subwoofer channel, but that is not the same thing as saying the subwoofer in a typical home theater is driven only by it.

I remember reading about an early mix of Jurassic Park (I think) where they put the T-Rex footsteps only on that 0.1 channel. For those viewers that had not configured their DVD audio properly, the thunderous footsteps were gone, and the T-Rex gave the impression of tiptoeing through the jungle.

In the same light, how critical is doing a mix for the center audio channel? I know the purpose is to anchor dialogue, but I wonder if people are so used to doing that automatically while listening all these years to just a L and R channel.

>Yet you hear all the time about how in 5.1 the ".1" is the subwoofer channel, but that is not the same thing as saying the subwoofer in a typical home theater is driven only by it.

l also assumed the ".1" was the subwoofer until I tested it. Turn off your LFE channel and you'll still hear bass from the sub-woofer.

>In the same light, how critical is doing a mix for the center audio channel? I know the purpose is to anchor dialogue, but I wonder if people are so used to doing that automatically while listening all these years to just a L and R channel.

You mean doing that "mentally"? With my new M-Audio LX5s, I'm finding incredible differences in mixes with L and R instruments and instruments that have been mixed to both L+R (i.e., "Center"). The sense of location is so much better than "regular" speaker systems. I mean, I can just "see" instruments right where that C speaker is, even though the C speaker is off. This is so striking that I've abandoned my old preconceptions of LR mixes and am definitely using the C channel as well. *Much* to learn, though, not even counting panning across FL<->C<->FR. Personally, I've been doing some simple mixes of taking my onboard video stereo mic and feeding it to both FL, FR and C (panned front and center), then adding stereo music to FL, FR, RL and RR (panned to the surround center). The music sounds great on 4 channels, and I can really make the "action audio" stand out clearly by pushing the center channel. It *does* require listeners to re-educate their ears though, but since we now have so many more options with 360deg spacing I think its worth it. (P.S. I'm not advocating a "let's all go back to quad" movement, but I've always used 4 speakers for my audio setup and I much prefer its feel. Also, all my naive, uneducated audiences seem to agree :-)

Well guys, seems I stiired up some dust.
I am still experimenting with all the info I received so far.
I fear it's not all that straight forward.
Since most stereos and sourround systems have subs nowadays, in my opinion the LFE is a very important channel to employ, even for ordinary stereo music, not only for movie effects like proudly strolling TRexes.
Listen e.g. to the Streets of Philadelhia of Bruce Springsteen (and most of the other Boss's stuff). Unless you have a sub you won't experience the (e)motion the moment the synth kicks in.

Thank you all so far.

DKE: I think the point RichMacDonald makes in referencing the Dolby text is that the channels are full-range already. If all you had was L and R information, the sub on a home system would still be busy reproducing all the low frequencies in those channels. The .1 LFE channel was apparently meant for special effects.

Yep, your right.
Anyway, I deleted the LFE track and am awaiting results (rendering takes a lot of time and I can only check results over my surround system).
The LFE track was a duplicated track from the music track.
So now I have two sound tracks in total where I had three, the LFE track being a copy of the sound track having music only.
I hope my subwoofer will still respond to the music track.

Another thing I noticed is that I hear music coming through the center speaker which is not supposed to be the case.
In the surround panner I unchecked the blue center speaker so it becomes grey, which I think is the proper way to do in this case.
Only the original sound track of the camcorder should be passed through the center speaker. At least, that’s the way I set it up.
I don’t know what caused this.