The first step in sound system tuning is making sure that
the microphones are all sensitivity matched and if you only have two
microphones probably the easiest thing to do is point them and each other like
this and then you can have the capsules on the microphones orientated like this
that's why you get the capsules as close as possible to each other because I have
three of them and I don't want to have to run back and forth between my
computer in here then I've just pointed all of them at the speaker getting the
capsules as close as possible so that sounds kind of arriving all at the same
time because what I want now is to see in smart I want to see all the same
information because it should all look the same coming from the speaker okay so
I just shut the speaker up here freestanding important part of this is
to get this away from the floor and any other walls and surfaces that would
create reflections because we don't we want as little interference as possible
so I'm thinking about the three to one rule in terms of how far away the
microphones are from the speaker and how far away the speakers from the ground so
the microphones are three times the distance from the reflection path might
take from the speaker to these microphones seven basically just trying
to create as few reflections as possible that might influence this measurement I
know there's gonna be some because we're still inside and there's no noise here
but this is a pretty good situation and so now I can go take a look at sorry
alright so now that I'm in smart I have my audio input set up over here so let's
pretend like I hadn't done this already so I've got my reference input then my
first microphone and then the yellow and green microphone that I'm gonna make the
correction curves for and match sensitivity to check the output devices
and I'm gonna go over here and create my transfer functions so I've got my 7150
make sure it's got the right input and reference signal and then my yellow and
green make sure those have the right input and reference signal and then I'm
going to create spectrum measurements I think those are automatically created so
just checking that those have the right inputs so then I head over the spectrum
view and press the zero key and when I turn on pink noise all right so this is
where I lost my audio so I'll just do a voiceover narration from here so just
verifying here that I'm receiving all inputs on all channels and here I'm just
checked verifying my delay times and my coherence trying to make sure I have as
close to 100% coherence as possible averaging five six seconds and you're
just showing that even though I matched levels as well as I could I still don't
have matching data throughout the frequency spectrum so the first step is
just to select the reference trace copy of dasky paste it into this calculator
from Nia create schreiber and then copy the next trace
and then I'm going to create the microphone correction curve for taking a
look at this you'll see that sometimes you get error messages here and usually
I just ignore that if I know I have pretty good data then I want to save
this sheet as a comma separated value file and I'll just give it a name
something that is obvious for me in the future let's just say the active sheet
continued and then now I'll create copy that last
race and do this same thing paste it into the difference of curves
calculator and save this sheet
you
all right now I can import those microphone correction codes so I'll go
to options microphone correction curves I can see I've already imported them
there before but I'm going to do that again
and now I can put those microphone correction curves on my input so on
input three and four
so if I took a look at the live inputs here and I open up the microphone
correction curves then I will
but turn on the microphone correction curves
and when I run the live measurement again you'll see that now they lay on
top of each other and I have much more closely matched data than I did before
without the microphone correction
all right so I hope you enjoyed this more detailed video of how to use the
difference in curves calculator and there will be a link below this video
where you can download that calculator for yourself