Looking for 5.1 sound tutorials.

blink3times wrote on 7/3/2009, 6:13 PM
I'm looking for some DETAILED tutorials on Vegas's 5.1 sound editing. Ones that will fully explain everything... including the different pan types and their various uses.

I've played around with the 5.1 sound for a few years now and managed to muddle my way into a basic understanding.... but that's no longer good enough. I bought Spot's book in hopes of grasping a full understanding but unfortunately it was a little weak in the 5.1 department.

Anybody know where I kind find some really good, in-depth tut's on this subject?

Comments

DJPadre wrote on 7/3/2009, 9:28 PM
im dorry to say but not many people give much thought to it.

Your best resource is Dolby.com and onceyour licensed, get onboard their intranet (or extranet as they call it)

thign with vegas, is that there are many ways to produce a 5.1 mix., howeer in the ned, so long as you adhere to the regulations which Dolby Labs put forth, you wont have an issue whichever way you go.

To offer SOME advise, I only use "film type" surround. In addition, audio bed tracks are set with a different gain confguration to my dialogue centre channel, so as to ensure proper levels across all channels. I also tweak EQ's of the audio bed to ensure frequencies within dialogue dont clash or get muddled up or phase with freq within the music bed.

Surround mixing and mastering is alot more detailed than simple volume control envelopes and this is what alot of people dont understand. You hve a wider headspace (full 20hz at 448kbps) as well as 5 channels to mess with. its VERY different and u can get away with a hellofalot more than u coudl if u were workin in stereo alone.

Personally ALL my work is mixed and mastered at 5.1 simply because it gives me a lot more power whilst working

Aje wrote on 7/4/2009, 12:28 AM
I´m also looking for a 5.1 tutorial and have searched this forum for
5.1 issues but its seems not be so much discussed here.
When it is its mostly about a Sony cam that can record 5.1 audio
(I must say its hard to believe that an onboard mic really can do this).

I shoot mostly conserts, musicals and opera (musicschool) with 3 cams and always record 2 stereo takes.
One near the stage and one in the middle or back of the hall.
End product is dvd (with AC3 stereo).

Up till now I´ve just mixed the 2 stereotracks to one but
as I already have the depth in audio (front and back) I presume it could get better result with 5.1 audio with not much effort.
I have done some tests but I feel insecure and should really need 5.1 basic workflow tutorial.
Thanks for the link to Dolby.com I will try that but perhaps we are many here with 5.1 questions - why not start a 5.1 thread - I always get the best tips from here.
/Aje
blink3times wrote on 7/4/2009, 6:14 AM
Thanks for the link DJ... a wealth of info there. But actually what I was looking for was an in-depth tutorial set on how AC3 pertains to Vegas.

Vegas one of the few NLE's that goes as deep as it does into AC3... a lot of switches, dials, different panning methods and methods of adjusting....etc.

Unfortunately there does not seem to be ANY detailed info and/or technical answers as to what all those adjustments do and the various effects that they have. What I'm really looking for is a detailed guide on things like comparisons between pan types, details on the pro encoder and how the different adjustment on pro encoder will affect your sound....etc. With the level of detail that Vegas appears to be able to dig down to..... it's such a shame to have to kind of...... wing it due to the lack of detailed description and technical instruction.


Aje: "[/i]When it is its mostly about a Sony cam that can record 5.1 audio
(I must say its hard to believe that an onboard mic really can do this)."[/i]

Well, the 5.1 sound on these cams is really quite good.... but the addition of sony's ECM-HW2 Center channel Microphone REALLY brings it all home. Just an incredible (and authentic) sound and I would love to be able to get everything out of it instead of just plunking it onto the time line and rendering it out.
farss wrote on 7/4/2009, 7:22 AM
ac3 is only a method of encoding surround sound. The panning method etc has nothing directly to do with ac3 at all. It's the same if you encode stereo mp3 and how the various stereo pan pots work. It all works the same no matter what you encode the stereo or 5.1 to.

What the surround mic on your camera is recording is ambient sound, no different to when I record stereo with a stereo mic. Once recorded there's very little you can do with it. You either did it right by putting the mic in right location or not. Any attempt at fixing it in post usually only serves to make matters worse. That's a hard lesson to learn and one that's taken many audio engineers a very long time to grasp because we all think more has got to be better. If two mics sounds good 10 MUST sound better, wrong!

The problem with any on camera microphone be it stereo or 5.1 isn't how good the microphone is. The idea fails unless the camera is in the ideal location to record the sound. It gets dramatically worse if the camera moves. You are moving the sound field around and this sounds very wierd to the listener, it's bad in stereo, I can't begin to image how horrid that'd be in surround. You cannot easily correct this in stereo, surround would be even harder. Panning is not the same, it doesn't shift phase and therein lies the problem, phase is a major part of how we locate a sound source.

On the other hand if you're talking about mixing stereo or surround sound, that's a different matter entirely however most sound sources for stereo or surround mixes start out as mono, each sound source is close mic'ed with one or two mics with some care taken to limit phase errors. Then each sound is panned accross the stereo field or into the surround field. Some surround of say a band might be close mic'ed to produce a stereo front image and then an ambient stereo mic used to add a sense of place / space from the rear channels. I was lucky enough to hear such a mix in a monitoring studio, quite impressive. In fact some of the best surround sound I've heard, I really felt like I was in the building.

Bob.
blink3times wrote on 7/4/2009, 8:05 AM
Well, it's not really a matter of "fixing" anything Bob... nothing really to fix. I'm generating a rather good 3d sound field as it is now. It's more a matter of stretching the legs and finding out what exactly can be done.... much like adding a video effect to a clip.
MPM wrote on 7/4/2009, 8:29 AM
I think Bob nails it... For info on the actual recording, I've usually had good results hunting forums & such at sites where they focus on music recording. I usually learn something at Harmony Central. Same with mixing, editing, fx etc. Most of the mixing, routing, FX principles apply easily enough in Vegas, though I've never seen tons of Vegas specific info because, well, Vegas isn't the biggest, most popular, or coolest looking kid on the playground... Just looking at an Ohm Force filter can be fun, & there you've got the Sony plugin that might as well be wearing a pocket protector.

As far as Vegas panning goes -- how to use it rather than what you should put where -- I've always thought of it as mic placement. I know that's not entirely accurate, but it's just been the easiest way for me to think of moving around that little window, & so far (knock wood) it's worked. I've not to date found any better way to sort of visualize it.

For Dolby related, I've learned some stuff from the doom9.org & videohelp forums from occasional threads with people studying that sort of thing in college -- in fact some of the best stuff I've read was on edu sites, dealing with theories rather than what Dolby will tell you, but that's me. As Bob says, phase can play a major part, I think especially when you've got a downmix to stereo -- listen to a downmix from a commercially produced 5.1 track & compare it to the same track encoded by Vegas. The downmix process is hard coded in the player.

"how the different adjustment on pro encoder will affect your sound"

A lot of it is basically instructions for downmixing -- instructions to the decoder on relative levels. A quick, though maybe tedious way to explore what the actual effects are on audio tracks, is to disassemble your Vegas encoded 5.1 (in 1 of the besweet guis or whatever) without any processing at all -- then re-import & compare.