Low frequency analysis, this is the moment where you really
understand the nemesis of the modern production studio.
Most modern production studios, in fact,
most production studios period are small rooms,
small rooms compared to arenas,
compared to stadiums, compared to concert halls.
They're small, 300 square feet,
400 square feet, 500 square feet, 600 square feet.
These are relatively small rooms.
We don't see dimensions much bigger than 20 feet,
25 feet, sometimes even smaller.
Since equipment, besides getting less expensive and in my opinion bigger,
it's also gotten smaller.
Money's gotten scarcer.
So, everything has aligned itself up for our rooms to be smaller.
But one thing has not worked in our favor.
The frequencies that we're listening to seem to be getting lower.
Listen to most popular music.
So, we have a perfect storm of misbehavior.
What are room modes?
Most people associate room modes with the words standing waves,
and now comes one of the great myths in acoustics.
There's nothing wrong with standing waves.
In fact, if there are no "standing waves" in your room,
it simply means you're not in a room or you're in
a completely dead room or you're outdoors.
If you're in a natural sounding room,
you have to have standing waves.
There's nothing wrong with them. By definition, they exist.
So, to make us feel better,
let's stop calling them standing waves and let's start calling them eigentones,
and now all of sudden everybody's happy.
"Hey, I've got some eigentones in my room."
"That's good," and everybody's happy.
Same thing. So, standing waves, what does that mean?
All that this means is that these are the natural frequencies or modes based on position.
These are the natural frequencies where sound that's generated in a room from
a certain position and then listened in a certain position tend to be
reinforced or the node of that is they tend to be non-reinforced.
So, if you think about it that way,
of course, every room has standing waves.
So, why did they get a bad rap?
What's the bad deal on this?
Well, the problem is if the standing waves are not aligned correctly.
It's like saying strings on a piano are bad.
Strings on a piano are terrific.
They're just bad if they're not tuned correctly.
So, think of this as the way a room naturally tunes itself.
So, if you start thinking about it that way and then very quickly about how we
calculate these eigentones and then recognize that every room has three-dimensions.
So, it has three natural fundamental first-order eigentones
and then you can simply build a chart of the second eigentone,
third, fourth, fifth, etc.
Knowing that by the time we get to the fifth or sixth or seventh eigentone,
these frequencies start getting closer and closer together so
they don't really make a difference anymore as far as their spacing.
You can quickly realize when you look at the formula that the smaller the room,
the higher the first-order eigentone.
The flip side of that is really important.
The bigger the room,
the lower the first-order eigentone.
So, a room at a certain point,
if it gets big enough,
has a first-order eigentone below a frequency that we can even hear.
This is why you don't have standing waves in the Boston Gardens.
We have it. You just can't hear it.
So, my last conclusion is that the smaller the room,
the worse the eigentone or standing wave,
as you used to call it.
Problem is and we are dealing with small rooms.
That's basically my two cents.
Actually I, guess was a little more than two cents on eigentones.
But stop calling them standing waves and definitely stop being afraid of them.
There's nothing wrong with them.
They are your friends. Call them eigentones,
embrace them, love them [MUSIC].