Do you remember the Johnson Smith Catalog?
What is the Johnson Smith Catalog?
Dude, it was on like the back page of all your magazines as a kid.
>> Jason: Oh! With X-Ray glasses and stuff like that! >> Brian: Yeah, yeah yeah.
They had a parabolic mic.
It was like, "Hear a dog bark from a mile away!
Hear the wings of a bird flapping!"
Do you not remember this?
No, I don't remember that specific one.
It was a hundred dollars, so I never got it.
I got the fake turd instead.
Oh, well... wise choice.
♫ 'Cause I'm a Modern Rogue! ♫
[synthetic robot voice] Parabolic Microphones
The first time I ever heard about a parabolic microphone, was on 3-2-1 Contact and they
talked about how it was used in production to actually hear what was being spoken in
the center of the football field onto... what are you wearing?
It's... it's science, it's for science.
Okay, that's fine.
I think I saw it in like some sort of spy movie from the '60s and '70s.
They were always like clear plexiglass, someone with sunglasses perched on a rooftop.
I always wanted one of those spying devices.
Not because I thought I was going to get sensitive information or collect blackmail, just so
I could go up to people and go, "I heard everything you said."
You wanted to be that guy who had the upper hand?
I wanted everyone to know!
You realize, you can just lie and say you're that guy?
That's true, but that's less fun though.
Speaking of less fun, uh let's talk about your hat here.
Okay. We are going to make a parabolic microphone.
Tell me if I'm following this right, if I just had let's say a microphone by itself,
then it is gathering this much--let's say an inch and a half worth of sound, right?
Right.
Whereas when you put it in a parabolic structure, all of this gathers and focuses on here.
Same way, like a solar power facility takes a whole bunch of light and focuses it in one
spot so that you're able to boil all that water and so on.
You're doing the same thing with sound to get a greater fidelity, this is why we have
the Very Large Array, we have the uh Arecibo Giant...
>> Jason: Arecibo in Puerto Rico, yeah. >> Brian: Yeah, yeah. Exactly.
Yeah, we're going to make a parabolic mic that should drastically increase the sound
quality using this novelty hat, a paint roller, and a cheap lavalier mic.
We are like the MacGyver of garbage.
Yes, TrashGyver.
TrashGyver!
Forgive me if I'm jumping ahead here, but I assume that the theory is: a parabolic microphone
is going to focus all the sound on here to a microphone to give us greater amplitude,
but it just seems like there's no...
[gasping] Oh wait, I stand corrected.
Try this experiment, like keep in mind this is just fabric.
Fancy parabolic mics are made of plexiglass, they're super precise or whatever, but try
just talking and then talk into this and listen to the way your voice sounds different.
The parabolic umbrella is approaching my face and, oh yeah!
[much more prenounced in high frequency] Oh wow, it sounds dramatically different.
Right?
Yeah, it's just simple.
This works on the macro and the micro level.
For example, there are things called whispering galleries.
They are rooms shaped in such a way that if you stand in a particular place, you can hear
very precise sounds from very far away.
The story I heard is that there are negotiations that take place in whispering galleries, where
like let's say the French delegation shows up, and the Americans are able to listen to
them whispering to each other because the two negotiation points are precisely set up
at the foci of the ellipse of the entire room.
The Mayans actually created something like that as well at the Great Ball Court in Chichen Itza in Mexico.
No kidding.
Yeah, you can do the same thing and stand 50 yards away or something like that, and
hear everything with perfect clarity.
Okay, so the idea is, is that it's very powerful to--man I, even just now I grab this and I hear my
voice changing when I aim it the right way.
So it should work, right?
I think so.
First thing to do is get our base, and let's just test the lav and see how well it works
without this.
What kind of lav is this?
This is the cheapest you can find, I got this on Amazon, super basic, we're just going to
plug it into the phone.
Okay.
So if I hold it, let's say one unit, and we'll define a unit as my "hang loose" distance here.
So at this level it's receiving a certain amount of volume from me, the inverse square law,
because we live in a three dimensional world, means that if I go out one more unit,
you would think it would be half as loud.
Right.
But that's not the case, it is inverse of the square of the distance.
So instead of being half as loud, it is one fourth as loud.
And similarly, if we went out two more it would be one sixteenth as loud.
Because we're in 3D space, it dissipates so much with the sound wave that it drops off
very, very quickly.
So instead of being, whatever this is like a three millimeters wide of a sound aperture,
it's going to take all of this and focus it right in there, right?
Theoretically.
We'll see.
Let's get our base, and if you go stand over there, I will point this at you and record you,
and we'll see what kind of fidelity we get.
All right. Done and done.
You know what, if I were to talk it would probably be very variable, I might think I'm
being loud or quiet or whatever so I'm going to play something from over there.
Oh, Okay.
So you're about 28 feet away.
And I've got my phone, I'm going to set it to one level and I'm going to keep it the
same for both tests.
Okay, I'm going to hold it here at arm's-length pointed directly at you.
Okay, and I'm going to point the phone so the speaker's right at you.
You ready?
Recording!
All right, set in three, two...
♫ Grilled Cheese ♫ (track plays from our guitar episode)
♫ Grilled Cheese ♫ (it is tinny and faint, with plenty of room-tone and AC)
♫ Grilled Cheese ♫
There it is.
That's good, I like that a lot.
Okay, so uh how loud did that look like?
Not very loud at all.
You can barely hear it over the sound of the AC.
Oh, okay.
Yeah, but it's definitely there.
But it's working.
So now we'll make the antenna.
What are we doing?
We're taking our parabola.
Yep.
>> Jason: We cut off the head strap.
>> Brian: Yep.
>> Jason: And we're going to use a paint roller as our handle.
So is the thinking that a paint roller, just by dumb luck, happens to be right at the focal
point of all this?
I hadn't considered that but you're probably right.
I'm thinking we cut off all of this right here, and just use the bar inside.
Oh, yeah!
Okay so here, let's get the uh, where's the sledgehammer?
Let's figure out a way to also set it on fire.
Or we could just cut it off with the bolt cutters.
No...
No?
Just a little.
Just a little, right?
Just a little, little bit.
[unintelligible noises, but sort of sounds like a duck]
Okay, that went everywhere.
>> Jason: We're good.
>> Brian: There.
>> Brian: Now--whoa! Get that away, that's bad.
>> Brian: It's fine!
There's literally no reason to do this!
The Internet!
[aggressive hammering continues]
Well that was easy, why didn't we do that from the beginning?
I know!
That was dumb.
Uh, great!
That is a fine stick.
Yeah!
We made a stick, Jason.
Okay, where's uh, we need a knife.
Where's a knife?
I got a knife.
We're going to cut a tiny hole right there near the center.
>> Brian: Just one?
>> Jason: Yeah.
>> Jason: Okay, then we thread that through there.
It seems like the focus would be right around here.
This is the part where you totally have to kind of guess, so let's do this, what if we did...
[exerted grunt]
Oh, nice.
Okay, yeah cool.
Right?
>> Brian: So now it's farther out. >> Jason: Very cool. Yeah.
Like that?
Yeah.
Let's just use all gaff tape, gaff tape does everything.
>> Brian: You just keep giving me tapes, and we'll keep taping.
Does that look right to you?
Oh, it totally does.
Yeah, right?
Okay so now let's just reinforce everything.
We're going to have to leave a little room to get the mic threaded through there.
That's some damn fine craftsmanship.
I think so, yeah.
Looks pretty good!
Shockingly good, actually.
Uh okay, so here, if we ran this through-
Through the hole that we cut.
Yeah.
[Brian gasps]
>> Jason: Cool.
[affecting a grindhouse voice] Clown Spy, coming soon to a theater near you.
[continuing the grindhouse voice] America! You're not prepared for the terror unleashed by the Clown Spies!
>> Brian: So we point this down?
>> Brian: Towards the parabola, I assume?
Dude, that looks shockingly legit.
Look at that!
Okay, so I swear if this works I owe you a cheeseburger, because this looks so ridiculous.
All right, you ready?
So for this one I want you to try to aim it directly at the speaker,
and then, and we'll just get a clean take of the whole thing. You ready?
Okay.
Up a little, perfect.
Ready, three, two...
♫ Grilled Cheese ♫
♫ Grilled Cheese ♫ (very similar in fidelity to test 01)
♫ Grilled Cheese ♫
All right, so let's do it again.
This time I want you to do a sweep from the side, to eventually pointing at me,
and then, and then beyond.
Because I've got to tell you, I'm kind of thinking we probably need to reinforce it
with something that will bounce back the sound a little bit better than umbrella material.
♫ Grilled Cheese ♫
♫ Grilled Cheese ♫ (again, very similar to previous tests)
So here's the original.
So you can see it barely makes an impression on the waveform there, right?
Yeah.
Let's go parabola mic in stationary.
A little bit?
A little bit louder, and here is the sweep.
I think this one will tell whether or not we're getting focused audio.
So that's off.
And you can hear it definitely getting louder,
and you can hear it fading out. - Yeah.
There's definitely a difference, but it's not as big as I expected.
Yeah, it's a little disappointing.
I got a feeling that the fabric is our big problem.
So we've got these plastic cards from a new thing we're doing over at scamstuff.com.
What if we scaled this?
Because it seems like sound would bounce off the cards much better, right?
Sure, yeah.
Makes sense.
Then let's do this, here you keep tearing off little bits and I'll just start filling all this up.
So you're basically just making scale mail?
Correct, correct.
>> Jason: But with these fancy gold playing cards.
Right.
I think we're rapidly approaching the moment at which it makes sense to just buy an actual,
functioning parabolic microphone.
Yeah, I've got my fingers crossed.
>> Jason: I'm skeptical that we're going to see much of an uptick in sound quality.
Well we know that the real things work, because people pay tons of money for them.
It might be that the precision required is just more than we're capable of doing with
our setup, you know?
Or it might be that, uh we just have the wrong material.
Because the other thing that matters, is like, it does matter that the microphone be placed
right at the focus.
Yeah, that's key, right?
Yeah.
All right, let's tape it on the backside as well.
>> Brian: We're actually extending the range of the parabolic microphone by a little bit because
we went wider than the original umbrella.
>> Jason: Oh sure.
>> Brian: But, more importantly we've got a more sound-reflective material.
Okay, dude.
Think we've got it?
>> Jason: If nothing else- >> Brian: -check, check, check.
[gasp] Listen!
Check, check, check, check.
Oh yeah, wow, weird.
If nothing else it's going to look good on the shelf with the rest of the garbage.
[Brian making... transmission noises? I guess you would call them?]
All right, from the same spot.
Ooooh, come on grilled cheese, do me right!
Recording.
Three, two, one!
♫ Grilled Cheese ♫
You can hear the air conditioner much louder, but you're actually quieter.
Man, I wonder if we just had it aimed wrong.
Try this.
What happens if you back up?
No, it's definitely collecting all of that light and focusing it right here.
Let's try it from a shorter throw.
[Brian plays a blended synth tone, first a low frequency, then a sharp high]
>> Brian: All right, let's try it attached.
[same synth tones, low then high]
Dude, you can see the waveform changing when I change positions on this.
That is not a big difference.
No, it's really not.
Obviously a right idea, there's a reason that those microphones exist, but I think it requires
more precision than we're able to get with a novelty umbrella hat.
You think?
How did the novelty umbrella hat fail us?
I don't know.
Are you bummed?
I'm kind of bummed.
You know what?
I'm relieved, because I almost spent 120 dollars on the Johnson Smith Catalog's parabolic hobo-antenna.
It's not too late!
We want to give this thing as far of a shake as we can, so we replaced the cheap mic with
a good mic that we use for production, we're using the Zoom instead of the phone, because
it could be that the phone does some auto-gain stuff, and also instead of using the grilled
cheese song we're going to use bars and tone so that we can actually get true-math numbers
on exactly what kind of effect is happening, because clearly some kind of amplification
is occurring, but just we don't have sophisticated ears to hear it.
This is about as scientific as I care to get on a DIY umbrella hat parabola mic.
Okay, I'm going to go to the same spot.
I'm going to play that bars and tone.
Okay, you ready?
Ready.
We're starting with naked mic, by itself, with bars tone.
[sustained 1000 Hz tone plays, commonly known for censor beeps]
Okay, same spot, this is bars and tone with the parabolic mic.
Aaand, go!
[sustained 1000 Hz tone resumes]
[tone fades out]
[grows stronger]
[fades out again, birds chirping in the background]
Okay, so after controlling for everything, it looks like our tests showed that there
was a marginal increase in quality.
Very marginal. - A decimal or two,
but there was a vast increase in the precision.
Because we've got a lot of, we've got birds chirping up in there, we've got the AC.
It's much more directional using the parabolic mic.
♫ samples from each test ♫
(notably more room-tone than previous tests)
(shrill tone)
(effectively identical tone)
(smoother sustained tone)
(sharper clarity of tone)
(tone fades out)
So does it work?
Yeah.
Is it worth it?
Probably not.
Well, certainly not the way we did it.
Keep in mind also that we did not use directional microphones, we used omnidirectional microphones,
which probably effected the results.
But the point of this build, is that the idea is that you can cheaply and easily create
a high-precision instrument, and I gotta give this one a fail, right?
Yeah, I mean it looks super cool and-
It looks badass!
It looks kind of like a psychotic person built it.
Sometimes these DIY builds are shockingly good, like as good as the pro equipment.
In this case, I'm going to say, for the fidelity of the instruments, and for the level of precision
you get, probably not worth it.
Do it the old fashioned way!
Dress up like a ninja and hide in the shadows.
Is that what you recommend for invading people's privacy?
I mean that's what I've been doing at your place for...
[the whooshing sound of a blowtorch in the wind]
[muffled hammering] -- CC BY BIZARRE MAGIC IN CONJUNCTION WITH VIEWER-SUBMITTED CAPTIONS --