Tip:
Highlight text to annotate it
X
Hi I'm Rich Clingman with AudioGearFinder.com and in this video were going to talk
about
comb filter and how
a reflection of sound mixed with the original sound
can cause a distortion,
what is known as comb filtering. We're going to look at what that is
and we're going to cause some. We're going to use a
headphone microphone and going to use an iPad
to generate noise and we're going to actually bounce it
off of the monitor here
and we're going to compare that with
an acoustic panel and see how the acoustic panel
can help to control reflections.
I am using here a daw - a DAW -
that is Studio One - PreSonus
PreSonus.com. You can see here
a spectrum analysis -- you can see a spectrum
of this and what we are going to look at
is some white noise.
You can see the white noise is fairly regular
now let's see
what happens when I move close to a reflective surface. I'm just going to
take this -- and quit talking -- so you can hear this sound.
If you have some headphones you can hear the difference
in the sound quality, and you'll also see that you get some notches.
So a couple things to look at in considering
recording and to minimize comb filtering issues,
One is: The higher the level of
of the sound in the original signal, you'll see that with this
high level of signal here that
even when I move close I don't see the level of comb and the tone change that I was seeing before.
If I move the microphone away you can see I already have comb filtering.
So one of the things to control comb filtering is
to have the microphone as close to the original
sound source as possible, and if it's
a cardiod, to have it pointed
at the sound source with the
back or the rejection part of the microphone toward
the closest reflective surfaces.
And just as another example here
if I move this close and I'm getting that
comb filtering, what if I was moving close to an acoustic
tile...
versus not with an acoustic tile?
So acoustic tiles are not intended to be soundproofing.
A lot of people think these as soundproofing.
What they're intended for is sound control
and especially reflection control, to control
any reverb, any echoes, and also the comb filtering, especially on close surfaces.
So that is
talking about comb filtering, particularly in recording
and how using a microphone correctly
near the source for the greatest signal and rejecting any
reflective surfaces as much as possible. This is Rich
Cingman. I hope that's been somewhat informative.
Thanks.