Creating a LFE channel

Geoff Edwards wrote on 4/28/2006, 9:47 AM

HI Guys,

I want a rumble sound to activate the sub on a viewers system for a short film project I am working on. I don't have an LFE channel appearing on my work space right now... Can anyone tell me how to make sure the sound plays from the LFE channel. I suspect I need to assign the audio but don't know how to do it.

Thanks for your help.

Geoff

Comments

DavidMcKnight wrote on 4/28/2006, 9:53 AM

Your project needs to be setup as a 5.1 surround project. That setting is in the project properies; I don't know for sure if you can change this once you've started, but I would think you can.

<edit>
File - Properties - Audio - Master bus mode = 5.1 Surround

Geoff Edwards wrote on 4/28/2006, 10:33 AM

Thanks for the reply. The project is a 5.1 surround project and was from the start... I just don't have a LFE Channel for some reason.

Jay Gladwell wrote on 4/28/2006, 10:34 AM

You have to right click on the given track Surround Pan window and assign it to LFE.

craftech wrote on 4/28/2006, 10:47 AM

Don't forget to set the crossover. Consumer 80 Hz is probably your best bet.

John

Geoff Edwards wrote on 4/28/2006, 11:04 AM

Thanks very much Jay. I knew is would be a simple setting but I just couldn't find it with the search words I was using. Got it!

MRe wrote on 5/2/2006, 12:18 AM

Just my 0.02 € worth. This 5.1 editing plus "correct" use of LFE has bugged me all the time since I upgraded to V5 and started to edit all of my projects on 5.1 sound.

My standard setup is that I designate one extra bus for LFE (or subwoofer) and then use envelope to direct required amount of sound to that bus. This way the sound is also coming from other speakers (depending on the surround panner) giving a bit more depth to it.

Or am I completely lost here?

DJPadre wrote on 5/2/2006, 4:05 AM

u can do it in many ways.

I run a crossover of 120hz, as that is the Dolby Digital standard, and being licensed means i have to follow the standards... aside from that when allocating an LFE channel, i do it by track. Assigning a bus is possible, but its usually much more fiddlier than simply allocating a seperate track altogether, this way the LFE channel is isolated.

another thing abotu the LFE, (as well as doing this on the bus "route",) is that you SHOULD allocate a compressor on the LFE channel.
God you know what, i can go on about this for hours, but i wont..

with LFE, ther eare afew paramount rules, and the most profound is to NEVER go over 0db (I would actually say -12.. but ... ). Vegas has the tendencay to do this when u duplicate then convert a track to LFE..typically for music. V5 had the tendency to randomly blow out the LFE channel to +17db, literally blowing the sub.
DONT EVER let the LFE channel/track/bus go over the treshold.. not ever.. even if yoru mixinc for Dolby DIgital and youre wanting to compensate for the normalisation DONT go over 0... (-12 IMO, but 0 is USUALLY ok..
If it peaks your screwed...

A good safe filter to use when usin teh LFE is sonic foundrys own clipped peak restoration, with a -6db limiter. this helps immensly. Anoher thing, DONT mess with the EQ. The LFE is specifically designed for Low Frequency Effects. Your NOT supposed to hear anything else on that channel apart from teh Wow factor rumbling and low freq signals such as a bass guuitar, cello or kick drum etc etc for muic or EFFECTS for movies. Its nto a channel to be taken for granted if you dont know what youre doing with it.. Sure it has the wow factor element, but its probably THE most important aspect of Dolby Digital encoding (apart from centre channel of course.