I just published a new article so I thought this would be
a good opportunity to show you some of the updates I've made to the aiming
triangles business card so this article is all about placing and aiming your
stage monitors for maximum gain before feedback to get maximum gain before
feedback you need maximum rejection and to do that you need to place a name your
stage monitors well so that they're aimed right into the null point of that
microphone I really like this product that dave RAC created called the polar
pointer now you can mount this in a mic clip then look at where the lasers point
for a super cardioid or hyper cardioid microphone and then place your stage
monitors in the exact right point and then I thought I wonder if I could just
update my aiming triangles business card to make it sort of like a poor man's
polar pointer so over here you can see I wrote a drill in new lines one for super
cardioid and one for hyper-cardioid so super has its own line here which you
can see is also going to be over here on the left in between 50 and 60 at 55
degrees and then hyper is this line that it's almost touching right below here so
how might you use this in the field well if you take the aiming triangles
business card this is the old one but I'm gonna show you the demo you could
put it on top of your microphone like this right and then you can see where
the laser is pointing on the ground and put your speakers in the right place
point them at the microphone and this should be pretty precise the other cool
thing is that then you can sort of rotate it around the microphone like
that because the pattern is in all the way around the microphone nut right it's
not just 2d it's 3d so I could have it here in the clip and then sort of rotate
it down and see where my options are for placing the stage monitor a couple of
things to keep in mind with this it's not perfect you can't just look at
any microphone and say oh this is a super cardioid microphones so I'm just
gonna use Nathan's aiming triangles business card I looked at several
different microphones and it seems like there is no industry standard for
exactly what that means over here we've got the shure beta 57 a which calls
itself a super cardioid and says my no points are at 120 degrees we've also got
the bear dynamic m2a1 which calls itself a hyper-cardioid but
has its no points at the exact same place so here's an image from the shure
spec sheet and here's an image from the bear dynamic spec sheet
can't agree I don't know why I guess we need to look up the spec sheet for every
microphone that we use that's fine we should know about the hardware that we
use it would just be nice if you know people say hyper-cardioid and they need
one specific thing that's okay just keep that in mind that even though I wrote I
drew those lines in a specific place on this card it might not be exactly there
for your microphone okay so that's the front of the microphone let's look at
some of the updates I made to the back now I know you guys hate it when I
introduce information and then don't say what it's for or why is valuable so
below this video I'm going to add lots of links that will teach you more about
this stuff but if I were to try and explain all the stuff on the back of
this little card it would take me I don't know five days so this is a little
table here to help convert from coverage angle to forward aspect ratio and
lateral aspect ratio and backwards if you need to and down here are some
calculations if you need a number that's not on this list so if you have a
speaker that's 65 degrees and you want to calculate the forward aspect ratio
and lateral aspect ratio you can do that with these equations down here let's
look at some more helpful equations here we have time to frequency and vice versa
so one divided by frequency equals x so if we wanted to find the time period of
1k that would be 1 divided by 1,000 which would be one millisecond okay so
0.001 seconds if I want to find the wavelength and I know the frequency and
I just need to divide the speed of sound by the way so down here we have some
options for speed of sound let's say I'm working in feet so 11 29 divided by 1k
you me a wavelength of 1.1 to 9 feet
here we've got your phase-two time conversion this is really helpful when
you're doing something like a main sub alignment and you've got you're looking
at two-phase traces and you can see that they're I don't know six degrees apart
at 100 Hertz so you could say okay what's 60 divided by 360 divided by 100
Hertz and we can see that that's one point six seven milliseconds if I
multiply this by a thousand that's more clear one point six seven milliseconds
some helpful estimations here for converting distance to time and vice
versa I used this one a lot 0.9 milliseconds per feet when I'm setting
up an estimating an inline two element gradient subwoofer array I know that I
need to delay the rear sub by the spacing distance so if I measure the
spacing distance and I see that it's three feet then I can just multiply
three by zero point nine to get an estimation of two point seven
milliseconds delay for the rear sub and then finally over here I've got a tiny
little linear to log conversion chart these are the five big ones that Merlin
vanveen recommends that you memorize and I'll put a link to his video below this
video say for example that you know the front to back distance ratio of your sub
to your audience is one two three then you can expect a 10 DB contrast from
front to back not taking room gain into account
alright so those are the updates to the aiming triangles business card please
let me know what your suggestions are I don't know if I can fit more information
on this card but if you see something that I did wrong or some way that I
could organise this better to make it more useful to you please let me know