Those of you who are acoustically challenged

Bill Ravens wrote on 10/10/2006, 7:24 AM
yes, this is a video forum. But, it seems there's a few folks who don't know their octaves from their resonances. here's a helpful little piece: http://www.electroacoustics.co.uk/article/essroom.htm
The audio portion of a video can make or break a piece. If the ears get tired, watch your audience start to squirm and lose attention with the video. Since videographers are primarily that, and not audio engineers, they tend to not understand the dynamics of vibration. There are even some of you who look down their noses at "pro's". Ah well, bunky, I feel for ya.

Comments

kdm wrote on 10/10/2006, 7:53 AM
Great point Bill. I see $20,000-$50,000 video projects go to DVD without a single dollar spent on audio (or music). I've seen some of these projects on air - the lack of planning and allocation of budget shows (both audibly and visibly). The clients are spending a lot and getting little.

"The audio portion of a video can make or break a piece."

Can I quote you on that? (so my clients aren't just hearing it from me).
Coursedesign wrote on 10/10/2006, 8:20 AM
Hey Bill,

It's called video for a reason - it's all about the picture!

If the people who watch video cared about the audio, they would be called the "audience" or something.

Umm..., never mind!

:O)
Jay Gladwell wrote on 10/10/2006, 9:00 AM

Deep trapping, Helmholtz and membrane absorbers and resonant pipes may be used to control low frequency decay, but because low frequency propagation is primarily by excitation of room resonances, close attention must also be paid to the shape of the room.

Huh...?

And what about those formulas!? The only formula I've ever had any success with was baby formula, and even then it was usually spit back up on me!




Bill Ravens wrote on 10/10/2006, 10:04 AM
hehehehe, coursedesign...

Jay.....
needless to say, hardly trivial, is it. fortunately for us all, someone else can worry about the mathematical algorithmns. all we have to do is understand the principles and learn the tools.
Spot|DSE wrote on 10/10/2006, 10:41 AM
This is why we say (around here anyway) that "Sound is 70% of what the audience "see's...."
richard-courtney wrote on 10/10/2006, 2:37 PM
I have no idea what you said......
That is why we rely heavily on those experts that have experience in music and
sound such as Spot/DSE.

My wisdom can only recommend a super pair of headphones ($100 or more)
when recording. The cheap ones you cant hear low frequency very well.
Jay Gladwell wrote on 10/10/2006, 2:55 PM

Bill, I was just being silly. I would never suggest that sound is trivial!

But in reality those formulas are truly over my head. I simply can't wrap my brain around such concepts. Advanced math was NOT my best subject!


Coursedesign wrote on 10/10/2006, 3:23 PM
Who can get motivated to learn math the way it is taught in schools still today?

Research has shown that kids who can barely add 2 + 2 can whistle right through differential equations after somebody talks about how it makes cool graphics for video games.

In other words: present the problem first, then the solution!

Jay Gladwell wrote on 10/10/2006, 3:55 PM

Bjorn, when they were trying to teach me differential equations they were just figuring it out for themselves, it was that long ago. Newton hadn't even gone to the orchard yet!


Bill Ravens wrote on 10/10/2006, 5:45 PM
hey, truth be known, those fancy equations are for the laboratory. I trust my ears. I've just learned that my ears can be misled by room acoustics, microphone and speaker acoustics, and popular wisdom. I give my customer what he thinks is great, even if I disagree....that's just common sense. Question is, how do figure out what my customer wants....hehehehe...there's the challenge. A lot of times, these local rock bands just want to make it big. So what do they think is good? More often than not, there's one guy in every band who knows his stuff. ...no snow job will work there...I gotta give him what he wants. And, I gotta know how to manage the sound to give him "the sound". A lot of these lead vocalists got an ego bigger than Michael Rodney....LOL. The sound has to be good on a boombox, a theater stage and a car radio....damn, perfect is close enuff.
Serena wrote on 10/11/2006, 1:03 AM
>>>what about those formulas

When Prof. Stephen Hawking was writing "A Brief History of Time" his publisher suggested that each formula used would halve sales. Nevertheless Hawking used one: E=Mc**2. Why? Because no other decription is dramatically clear.

Similarly those equations about room acoustics. Very simple and by looking at the parameters you immediately see what's important. You don't need to use them; they just aid understanding.
farss wrote on 10/11/2006, 1:49 AM
An elder gent that I had the privelege of working with many decades ago planted something in my head that really stuck.
The ancient Greeks knew more about acoustics than we do today.
Reason being that they didn't think of sound as having frequency, instead they thought about wavelength. Now for anyone with an even trivial understanding of physics you'd think that trite. But those Greeks didn't have our knowledge of maths and it seems they didn't need it either. They were able to build acoustic marvels where an orator could be heard by the assembled crowds of thousands (and without going to 11).

Bob.
TorS wrote on 10/11/2006, 2:08 AM
Bob, you are saying Pythagoras did not have our knowledge of maths? He certainly didn't have mine.
Tor
farss wrote on 10/11/2006, 3:05 AM
I was referring to calculus and all the stuff that came after Newton.
TorS wrote on 10/11/2006, 3:59 AM
Still, the Greeks could've outnumbered me any day.
Tor
Jay Gladwell wrote on 10/11/2006, 6:14 AM

Bob, this past week-end the wife and I went to the opening of the new Performing Arts Center in Miami. The concert hall (seating 2,000) was designed by some acoustician to have "perfect acoustics"--no need for electronic amplification.

Michael Tilson Thomas, the conductor, was able to speak to the entire house without a microphone. The orchestra sounded surperb!

The specially shaped ceiling above the stage is raised and lowered and giant baffles along each side of the hall are adjusted to "tune" the room, depending on type of music/performance is being presented. It was a unique and wonderful experience, for me, anyway.


Bill Ravens wrote on 10/11/2006, 6:26 AM
Tuning your own studio is fairly easy..if not a wee bit expensive.
Sound Forge has a pink noise generator. Play the pink noise file thru one speaker and record to the other channel with a microphone. Look at the resulting EQ plot against the pink noise EQ. This will show you where the resonances are....resonances are kinda bad because you really want a flat EQ curve(really falls off 3 dB/octave). In order to tame the resonances, you need to start putting diffusers and absorbers in your room to correspond with where on the EQ curve you're experiencing resonances. Peaks in the EQ curve at low frequencies usually are resonances coming off the floor. Not much you can do about that, except try carpetting. High frequency peaks are resonances coming off the walls, usually from the reflections in the corners. Acoustic foam in the corners of the room do wonders...it tamed my own sound studio. Traps are a little more expensive. You may not be able to control the acoustics in the field, but, you can sure control any added distortions in your editting studio. Then use any good acoustic tool, be it Ozone, Waves, HarBal, or whatever to tame those peaks.
Jay Gladwell wrote on 10/11/2006, 8:12 AM

Bill, I would love to "tune" my editing room!

Auralex has "room treatment systems" (foam installations) for that, but my major concern at this time is the noise my computer makes. Unfortunately, I'm not able to chuck it and buy a silent computer.

Do you (or anyone else) have any suggestions as to how to reduce fan and disc noise?


Bill Ravens wrote on 10/11/2006, 8:50 AM
the best you can do if your computer is in your studio is to build a separating wall between the computer and the talent/mike. most computer noise is fairly high frequency and won't propagate around corners. i have roll around frames 4ft x 8ft with 1/8 inch masonite to which I've glued auralex foam. this allows "building" temporary sound rooms around a recording session. i've found that my own moving around at my computer while I steer my DAW during a recording session gets picked up by the microphone. It really pays to have a seperate control room. If yu can't manage to do that, sometimes having a noise gate helps alot. Noise gates work better in post than they do during the live recording. The single biggest thing you can do is record at the highest gain you can get on the mike without getting feedback. This improves the s/n drastically. A good quality compressor helps a great deal at being able to maximise that gain setting. Vocal talent, even the best of them, have quite a dynamic range, moving close to, then back away from the mike. An inline compressor really helps level the recorded audio a great deal. Then, apply the gate, judiciously, during post.
Coursedesign wrote on 10/11/2006, 11:25 AM
Bjorn, when they were trying to teach me differential equations they were just figuring it out for themselves, it was that long ago. Newton hadn't even gone to the orchard yet!

It just pisses me off that teachers are presenting math like IT is the problem.

Math is the SOLUTION to a whole bunch of problems, so why not present it as such?

Math is a tool, good to have in the toolbox sometimes!
Bill Ravens wrote on 10/11/2006, 11:31 AM
IMHO, academic subjects are taught by academicians. By definition, these are NOT application oriented people. They barely understand the reality of the street. They are great in a classroom or laboratory, but, heaven forbid they should have to do anything practical. Of course, I'm stereotyping....and there's always exceptions.
Jay Gladwell wrote on 10/11/2006, 12:59 PM

It just pisses me off that teachers are presenting math like IT is the problem.

While I agree with what you say, I also think it is an individual thing, too. By that I mean some are more gifted in conprehending some concepts (such as math) over others (such as art), like a talent. I simply do not have a talent for any form of advanced mathematics.

I didn't mean to imply that it was entirely my teachers' fault. I was there, too, and I simply wasn't able to grasp how it worked. I still can't, although I do try to readdress it from time to time. This thread, for example, is one of those times.


GlennChan wrote on 10/11/2006, 5:26 PM
I think the problem with math equations in acoustics is that they don't perfectly model what happens. i.e. if you read F. Alton Everest's book, you see that the measured results diverge from what the theories predict. There's a lot about acoustics that we don't know.

2- At some level, some details are too insignificant to be bothered with. Talent and creativity probably makes a bigger difference to the end product than what room you mix in (*I don't have very good ears).
Heck, politics even plays a part in the end product. There's lots of overcompressed songs out there, in a bid to make the song louder and stand out.
Bill Ravens wrote on 10/12/2006, 5:50 AM
man, you got that right, glenn. In my business, digital modelling is really BIG. Modelling works great for predicting trends, but, unless the model is calibrated against real life, it's worthless at predicting reality. When you get right down to it, empirical knowledge really is the best. Either you got the ear or you don't. No way to read a book to learn to have the ear. And some people are born with it...others struggle their whole lives and don't quite get it.