I decided to be Deadmau for Halloween, but wanted to take some creative liberties and go beyond basic black , blue , or red.

There are a lot of How to's, and guides out there - and I used pertty much everyone of them to consolidate my information into how I did it.

so here we go

2 main parts; Head / Ears, and Electronics
you can leave out the electronics if you want... but its worth it.

Step 1: Materials (head)

Head shell $60 : I saw someone making a sphere out of fiberglass, if you have fiberglass experiance - this might be a cheaper option. but I didn't have any "parts" lying around to save me any money so I would have had to get everything - and teach myself fiberglassing on probably the hardest things to make out of fiberglass - a sphere. so I went for a Light globe:
not endorsing them but when i was looking around they have the best price : http://www.superiorlighting.com/
now I am a Big guy (6'4") so i scaled up from other deadmau's heads online that use a 14 in globe - I went up to 18 in - to stay in proportion with my big body.... I also paid a little more, and waiting till it came in stock to get the "clear" not white, you'll see why later.
you can get a threaded or non-threaded gloabe - you will most likely have to make the opening bigger anyway.

Eyes $8 (total): same store online - only 6 in white. two of them

Ear foundation$8: I used Foam core - carft board, 1/4in thick paper on each side, its easy to work with and light weight. make sure you get peices large enough to make one ear - I got two ears from each board, but each ear is 4 layers thick - so 2 ears a sheet / 4 layers per ear * 2 ears = 4 sheets at about 2.50 each.. got them from a local craft store.

Covering $4: I saw people struggling to cut pieces of fabric to wrap a sphere, and I did not want a "shaggy" fur (that would cover bad seams) i wanted a very clean tight look, so I was looking for a 4-way stretch fabric (black)... but after I stepped up my idea to include LEDs in the Ears - I decided I wanted a fabric that would "sheer" to let the light of the led's through - but appear to be a solid sheet of fabric and easily cover the ears and head.... Pantie Hose.... you'll need "a leg" for each ear, and a set for the head... you will also need a leg for the teeth but those need to be white...

Teeth (free): I did buy a wire mesh food cover the other diy's talk about - if you are doing a standard size head - that will save you some time and headache, but it won't fit in my bigger head - so I had to make one out of wire hangers and some scrap wood....

Padding (free): I was going to use scraps from foam core- to add a "lip" to the mouth area - but found an old gym mat, and cut it up too (one of the diy's) use this mat, not sure how much it costs but I don't think one square is very much.

Hard Hat $8: I picked it up at amazon, surprised how cheap they are

Ear Attachements 4$: I picked up a 5/16 in threaded rod from home depot, and had some washers and nuts at home... this will be used to hold up the ears and in my design - attach my hard hat.

That is all you need for the Head - electronics
if you are not doing the electronics you can skip the next shopping list.

Step 2: Materials (electronics)

I am using an Arduino I had laying around from so that was free but you don't need a mega or anything, just 10 pins so the 2nd generation arduino I have will work fine.

Arduino $35: I would get it straight from arduino's site... up to you, I have not seen any for a discount

Microphone $7: http://www.adafruit.com/products/1063 there are a few ways to do this - but this was a good option in my book

Relays $20: I started to design a pcb to do this part of the work. I am going to run 12v DC to power the LEDs and the arduino can only push out 5v
After I started designing this I found a board that will do what I want - and has 16 relays (6 more than needed) http://www.sainsmart.com/
they ship from china - but it did not take long to get here and it was only 20 bucks! score.

LEDs 20-25$: my favorite component store is www.jameco.com but their leds (specificly green and yellow) were $$$$, so i looked around for the best place to buy bulk LEDs, turns out Ebay... just look for USA sellers - i order some from thailand - and still have not recieved them... it was my fault they had a 30 day shipping window, and I did not notice. USA shippers all got them to me quick. and you can find 100 leds in any color for about 5$ I got 200 Blue, 200 Green, 100 Yellow, 100 Red you'll see why later

Resistors and Wire 8$: Jameco.com - resisters are about $0.012 each... so i just picked up 200 for each Ohms rating I needed. you can never have too many resistors laying around when you are done.
I will talk about what resistors you need in the Planning LEDs Step.

Step 3: Electronics Planning

So the Idea is to have a Microphone that picks up the Noise volume in the room and Represent that level on the Ears of the Deadmau head.....

Easy right? well turns out not that bad -

First the Hardware....

LEDs
First pick your LEDs: if you have some laying around you can base your calculations off those specks, if not - find the LEDs you are going to buy:   you will need to know the LEDs Forward Voltage, and Forward Current. then you can cacluate the resistors you need to create your array.
when you are talking about using this many leds you need to use an array, use this site to help you figure out what you need to order.
http://led.linear1.org/led.wiz

I ended up using 16 leds in each "level" in each ear... so 32 LEDs per Relay
the first three rows (quiet volume) are blue
rows 4-6 (getting louder) are green
rows 7,8 are Yellow
Rows 9,10 are red

you might luck out and find leds with the same Fvoltage and Fcurrent , therefor could use the same resistors. but you might need 4 different sets of resistors, and you will have to keep them straight so you don't solder the wrong resistors to the leds.

you could use some type of PCB to connect these leds to resistors - but unless you have huge PCB blanks laying around - just soldering them to wires will be the cheaper and easier way to do this.

IMPORTANT
The Relay board I used - is a Sinking supply setup.
there is really no documentation on the board - to tell you this, and it took me a while to figure this out...
basically this means you run 12v to the leds, and connect the lead that would be grounded to the relay. that relay then chooses when to connect the ground (completing the circuit and illuminating the LED)
so as we wire this up, all the leds in the ear can be connected to the same wire (bus) of 12v straight from the Battery
the Ground from the Resistors will get wired into the relays

after using the array calculator I ended up using a 2 x 16 array layout or

12v ------------------------------------------                                12v connected to the Anode
                                                                   1st LED
            connection---------------------------                               connect the Cathode of led1 to the Anode of LED2
                                                                    2nd LED
Gnd -----Relay-----Resistor ---------------                             connect the resistor to the Cathode of led2 - then wire to relay board
                                                                                                   (it will connect to ground)

And I had to do that 16 times for each Row...... yeah its a lot of work - if you work that LED array calculator a little more than I did, you might come up with a better system, with less resistors, but there will still be a lot of soldering.

Remember - All the 12v can come from the same source, so you can run (one) 1 wire from the Battery to the ear, then connect all the (LED1)'s Anodes to that same bus.   the decision to light or not light is made by the Relay connecting the ground......
and on that note - all the 2 led arrays in one Row, can be connected together.
I ended up with 10 leads from each ear (one for each row - heading to each of the 10 relays) and 1 lead going to each Ear to provide 12 volts. so just because I have 160 arrays i only have 22 wires (not 320) coming into the head - and i connect Row 1 from the left ear, and Row1 from the right ear - so only one (1) wire going into the relay. same with the LEFT and RIGHT 12v, connect those to make only one wire going to the Positive terminal of the Battery.

The other connections:

the Relay needs to know what the 12v ground is, so each Relay needs a connection to the 12v ground as well (i feel like that should be part of the PCB but it's not...

then the Trigger 5 volts for each Relay needs a pin on the arduino

I also found that the Relay board will power 5 volts to the Arduino - so you don't need a separate 5v or 9v supply to power the arduino, just let the relay board power the arduino!

lastly make some room in the ear for the microphone. those 3 wires will need to get feed into the head and wired up to the arduino. the microphone I got said to use between 2v and 5v since it needs a steady current to be accurate - connect the 3v from the arduino to the microphone. ground it, and then you have a signal wire from the mic - that will be your analog in pin.

now get to soldering!

Step 4: Arduino Programming

ok so I may have gone a little overboard - you could come up with a more efficient way to achieve the same effect but this is what I am comfortable doing with electronics, so i am staying in my wheelhouse.

I wanted the entire ear to look like a VU meter....

found almost exactly what i wanted with some google work (i love the arduino community!)

http://robomaniac123.zxq.net/Robomaniac123/Arduino_Tutorials/Entries/2011/2/24_Arduino_Led_VU_Meter.html
and the code that came along side the Microphone...

I did make a few modifications to their code and I will include it.
basically that code above only takes the instantaneous volume, i modified it to take an average volume over 50 ms time. This smooths out the effect, and looks a little better for music playing during a party.

my Arduino Code ********************************************************************************

// Led VU Meter Example
// Version 1.0
// Written by James Newbould and Example Sound Level Sketch for the Adafruit Microphone Amplifier
// modified by Don Fouts for multi-array project

int led[10] = { 3, 4, 5, 6, 7, 8, 9, 10, 11, 12}; // Assign the pins for the leds
int leftChannel = 0; // left channel input
int left, i;
const int sampleWindow = 50; // Sample window width in mS (50 mS = 20Hz)
unsigned int sample;

void setup()
{
for (i = 0; i < 10; i ) // Tell the arduino that the leds are digital outputs
pinMode(led[i], OUTPUT);
Serial.begin(9600); // Uncomment to enable troubleshooting over serial.
}

void loop()
{
unsigned long startMillis= millis(); // Start of sample window
unsigned int peakToPeak = 0; // peak-to-peak level

unsigned int signalMax = 0;
unsigned int signalMin = 1024;

// collect data for 50 mS
while (millis() - startMillis < sampleWindow)
{
sample = analogRead(0); //hard coded analog in for mic
if (sample < 1024) // toss out spurious readings
    {
      if (sample > signalMax)
        {
        signalMax = sample; // save just the max levels
        }
      else if (sample < signalMin)
        {
        signalMin = sample; // save just the min levels
        }
    }
}
peakToPeak = signalMax - signalMin; // max - min = peak-peak amplitude
double volts = ((peakToPeak * 3.3) / 1024) * 10; // convert to value 1-10

//convert to output program code
left = volts;

Serial.println(volts);
if (left == 0) // if the volume is 0 then turn off all leds
   {
   for(i = 0; i < 10; i )
     {
     digitalWrite(led[i], LOW);
     }
}
else
{
   for (i = 0; i < left; i ) // turn on the leds up to the volume level
    {
     digitalWrite(led[i], HIGH);
    }
   for(i = i; i < 10; i ) // turn off the leds above the voltage level
     {
      digitalWrite(led[i], LOW);
     }
}
}

**************************************************************************************

Step 5: Assemble (head)

I decided with the 18in globe I could not just glue the hard hat to the top of the globe - my shoulders would get in the way.

so I had to lower the hat - so it fit, I decided trying to measure that would be pretty hard by myself, i did the entire project by my self.

I marked with tape where the ears should be, and where I could put the threaded rod that would hold them to the globe and the globe to the hard hat. then drilled the acrylic to make openings for the rod to pass...

lessons learned
Don't use a drill bit like the one pictured! find a bit that goes from 0-size you want without that step.... it cracked my globe.
I put the washers on each side after it cracked, but that would be a good security step before drilling as well.
Drill the holes in the globe and hard hat - bigger than the rod, not the same size. my holes were such a tight fit i had to twist the rod into both the globe and hard hat. if you use washers and nuts on each side of the globe / hat - the hole the rod is going through can be a little bigger.... this will save some time and headaches

After drilling the holes on the globe where the rod will attach the ears - I pushed in the rod and got a better idea where those rods would hit the hard hat.

marked those positions with a sharpie and drilled the holes in the hard hat. This really was more art that science, sure you could dust off the Trig from High school - but i eyeball'ed it and it worked pretty good. the hat ended up a little askew (so when i am looking straight ahead - deadmau is looking slightly to the left) but I can deal with that. learn from my mistakes.... thats why i am doing this.

Cut out the mouth. I used a dremel with a basic cutting wheel. steady hands are key - you can't really use a ruler to make sure you are following the line.

same for making the hole in the globe bottom - big enough to get your head in....

I put a fan in the top as well... just a quite computer case fan, they run off 12v so that was a no brainier to keep it cool in that head. air will flow through the pantie hose (ok) a little air flow will help a lot if you plan to wear this for any amount of time.

last hole you need are for the led wires. just in-between the threaded rod holes.

-----------------------------------------------------

Paint the globe black...... why did you get a clear globe if you are going to paint it? well the pantie hose idea was after I got the clear globe, and i a trying to minimize how many holes i cut into the acrylic to save as much structural integrity as i can. after you got the mouth - it is pretty fragile.

you can super glue (or hot glue) some braces in like I did - too firm up the mouth and keep it from cracking.

anyway - mask off the eye leds = and spray paint the rest black. this will give a black color behind the sheering pantie hose covering.

if you get a white globe - you can cut out holes for the eye leds, but you will still need to paint it black - or your head will look like black pantie hose stretched over a huge while ball...

Lips:
I used this gym mat to add depth to the acrylic where the mouth is, cut to fit, hot glue in place. (the hot glue works really well on this acrylic)

Eyes: I put 2 Blue LEDs in each eye. I hot glued them inside the globe, I did not drill out the acrylic (a good reason to use the clear globe - the light will go through. the hot glue helps diffuse the light so it looks like the eye is blue not like there are two blue lights inside the eye. but the eye globes were white. I have seen people use clear globes for the eyes. but then you have to sand the acrylic to make them white - or coat with some tracing paper to diffuse the leds... my system is pretty good i think.
Hot glue the while domes on the outside of the clear head.

Fan: hot glue in place (from the inside) so the outside still appears round.

You can connect all the wires for the eyes and fan together - they will just be on all the time the system is on. (i wired them into a switch i mounted on the hard hat.... so I could turn it off - without disconnecting the battery.

Cover the globe: this will be tricky - pull over the entire head. using hot glue and patients - cut around the eyes, and use glue to hold in place. same for teeth (attach the hose to the inside of the lip - mouth will be easier than eyes.)

Teeth: I tried to make teeth out of some hangers - it did not work..... i did not have time to resolve that issue - I decided to just cut two "buck teeth" .... a good solution - still considering it... it did make conversation with other easier, but it does show a good part of your face if you are trying to hide that...

Attaching the ears: after your leds are soldered in place, and the back and front are covered. wrap in hose, then slide over the threaded rod. if you want to glue them down you can but that will make it pretty much impossible to take the ears off to store without ruining the hose at a minimum. *post build note: I glued the crap out of those ears...... i choose durable rather than easy to store!

lessons learned: Mask over the inside of the Eye LEDs..... the reflection back into the head - made it really hard to see "out"
you need it dark inside this head!

Step 6: Wire Up

now you have a bunch of wires dangling around inside your head.... hope you marked the wires so you know what goes where.....

connect your two ears together,

at this point
your ears should be ready to connect to the relays, and everything else should be connected and in place on top of the hardhat.

I made a box to mount the relay and arduino on-top of the hard hat.... hope you wires are long enough to wire up just outside the globe, then shove it all in the globe and attach the hard hat.

the relays are kind of loud - and wanted to keep that noise down (the reason for the box) along with not wanting the relay and arduino dangling from the wired pins inside (or outside) the globe,

Step 7: Complete the Outfit

like I said I took some creative liberties with the idea - and Deadmau does not always where the same thing, but his suit with red 8-bit tie is a recognizable look for him.

I tried to get the 12v battery inside the head, but it was too top heavy, and uncomfortable. so I attached it to a belt and wore it under my suit jacket - running a wire up my back to power the head.

Video

http://www.youtube.com/watch?v=_Ne3aAPcqKA