Introduction: Robot Voice Modulator

Picture of Robot Voice Modulator

This is a simple to build device that converts your own human voice into a superior robot voice. It also includes a number of sweet features like an audio-in jack so that you can plug in all of your favorite instruments, microphones and music players, a vibrato mode and awesome pitch shifting buttons. It can be shifted two whole octaves in either direction. This provides for endless hours of fun (at the expense of everyone around you).

To here some crazy robot and pitch shifting action check out the file posted below.

Step 1: Go Get Stuff

Picture of Go Get Stuff

You will need:

- And IKEA clock body
- An adjustable fluorescent desk lamp
- A HT8950 voice modulator
- An 18-pin socket
- 4 SPST buttons
- Condenser mic
- Parts for the circuit (see next step for details)
- Wire
- 2 1/8" audio jacks
- A power source
- Misc hardware

Step 2: The Circuit

Picture of The Circuit

Breadboard the "HT8950 with a Transistor Output Stage and a 6V Power Supply" circuit found in the official data sheet minus the transistor output stage. Instead, wire that to an audio out jack.

Then solder the circuit onto a PCB, temporarily omitting things like the microphone, audio jacks and switches. This will be added later.

You can test to make sure the board works by adding extra hookup wires for the audio jacks and microphone and connecting them through a breadboard.

Step 3: Get Bendy Arm

Picture of Get Bendy Arm

Take apart your fluorescent desk lamp and remove the nifty bend arm.

Don't remove the lamp wire from inside the arm. You will need this to hook up your microphone. Therefore, don't trim it too close.

Leave the mounting bracket still attached at the bottom of the arm.

Step 4: Bracket Stencil

Picture of Bracket Stencil

Cut out a bracket stencil using the attached file.

If you happen to have an awesome Epilog laser cutter like we do at Instructables than you can use that to cut out the pattern onto a piece of tape. If you don't, an Exacto knife will do.

Place this pattern onto what you feel will be the back edge of the robot voice machine.

Drill out all of the holes with a power drill.

Step 5: Control Panel

Picture of Control Panel

Laser cut a control panel out of awesome transparent side-glow yellow acrylic using the file below.

If you don't have an awesome Epilog laser cutter than you can get the same effect with a jigsaw and a power drill with appropriate size bits.

Place the plastic clock face upside down inside the clock body and then rest the yellow piece snugly on top of it.

Step 6: Buttons

Picture of Buttons

Insert your push buttons into the acrylic. Wire together ground to all of the buttons and the other wire to the respective pins on the PCB.

Step 7: Mount the Bracket

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Mount the bendable arm to the clock body using nuts and bolts.

Step 8: Microphone

Picture of Microphone

Mount a nice-looking fitting at the end of the bendable arm and then solder and glue the microphone inside of it.

Step 9: Drill Some More Holes

Picture of Drill Some More Holes

Insert the clock face upside down into the clock body. Drill four holes to match into the upside down clock body to match the mounting holes in the corners of your PCB.

Step 10: Plugs

Picture of Plugs

Cut holes in the backside of the clock body such that you can mount your power jack, audio jacks and power switch.

Step 11: Mount the Circuit

Picture of Mount the Circuit

Pass the extra hookup wires for the microphone, jacks and power through the mounting holes in the PCB and subsequently through the holes you just drilled in the clock face.

Continue passing them through the clock body until they are out the back of the case. Twist them together to tie the board in place.

Step 12: Glue

Picture of Glue

Put a little bit of hot glue between the side of the front panel and the clock body at various points around the edge of the case.

Step 13: Wire It Up

Picture of Wire It Up

Wire up the switch to toggle between the audio in jack and the microphone.

Wire the power to the power wires and the audio out out jack to the audio out wires.

Step 14: Plug and Play

Picture of Plug and Play

Turn it on and let your owl rock out on the dance (apartment) floor intergalactic robot-styly.


CraigS12 (author)2015-07-08

I'm wondering if I would be able to do this for a cosplay and place the mic and speaker in a lower half, face resperator. And have the cable going to the circuit that's down on the hip. Would that be possible?

Aalexz (author)CraigS122017-01-19

Of course! Just make sure you're using a good enough amp circuit so you can't hear your voice!

The speaker output function can be found on the official datasheet of the IC, mentioned in the article.

ZarrarH (author)2015-06-21

Mark ChristopherD (author)2015-02-05

SIR can we have a copy of your circuit diagram of this project

Bmrshoot (author)2014-11-10

Building a transformer costume for my son, will this make his voice sound like a transformer....iron hide specifically.

gluvit (author)2013-12-21

Good stuff

LoSkana (author)2013-09-01

Ehm... the data sheet is now not available ^^

erikm1811 (author)LoSkana2013-11-29

The chip and the Datasheet is available at

JSWheeler (author)2013-07-19

The "data sheet" link is giving me an error.

synthdust (author)2012-10-19

Looks like he has two different circuits on that bread board. That little 8 pin IC is missing from the strip board... I think.

synthdust (author)synthdust2012-10-19

*perf board.

skydlimit016 (author)2012-07-18

is this expensive?????????

Michael_Bell (author)2012-03-21

Darn I dont have one of those chips. Mabey Marvin will loan me his space modulator, and I can use that...

Akash.C.A (author)2011-12-14

Where is the circuit diagram......?

gbarbadillo villanueva (author)2011-10-08

I´m trying to build the Voice Modulator and I´ll thank you if you tell me which microphone did you use.
Thanks a lot

AlternateLives (author)2011-03-05

Could you work this into a synth oscillator?

josh1324 (author)AlternateLives2011-05-29

I don't see why not, just replace the micro phone with the synths output.
And don't forget to hook the black wire of the mic to ground.

Ps. Did you make your own synth?

monsterman (author)2011-02-02

do yo remove the 200 ohm pot

oweng4000 (author)2010-12-24

That mp3 was hilarious

Volgon (author)2010-08-06

Where did you get the chip from? i checked all the usual places (radioshack, amazon, Frys) and i cant find it anywhere.

randofo (author)Volgon2010-08-07

Ebay. I got 10 for about $20.

Malccc (author)2010-07-04

hey,thank you very much!Im gonna give it a try~!

youn_link (author)2010-07-01

Can you pass the diagram circuit?

srmousse (author)2010-06-11

You get points for functionality and style!!! =)

mdnahid94 (author)2010-06-11

Please give me circuit diagram. Becoz I can try this.....

tinsolder (author)2010-06-11

if you'r too lazy to breadboard etc... check out for a Velleman mini-kit (MK171). Its also funny to bend it. and you can also use it for a stomp box.

SinAmos (author)2010-06-11

A HT8950 voice modulator chip. :( I thought you were going to do it electronically/mechanically.

codyduncan (author)2010-05-03

 What's going on on that board?  I see an extra IC and what looks like a transistor.

I'm thinking your "they can figure it out" scheme may not be the best policy.  I am trying to build this right now, but I am trying to avoid building it and finding that it doesn't work without  this or that extra component.

If you did add extra parts (it looks as though you did) what were they for?

SGplayer (author)2009-10-15


Foaly7 (author)2009-09-19

How big is this thing?

randofo (author)Foaly72009-09-20

About the size of a wall clock or stuffed owl. The circuit is pretty small. The casing can be miniaturized.

Foaly7 (author)randofo2009-09-20

Ok, and can you make the microphone attached to a cord that can be ran up, say, a jacket sleeve? I suppose you could, but how?

RPisces (author)2009-09-10

I have that same laptop lol

helios12 (author)2009-08-01

How much did all the parts cost?

Arnoldofingo (author)2009-07-29

~BINGO~ That's exactly -eh, what I was looking at... Now as I read through the threads (how could I miss it...?) it's all clear now. Thanks

Arnoldofingo (author)2009-07-29

you have a transistor; not listed in your 'to get' list... Wold be nice to know~

randofo (author)Arnoldofingo2009-07-29

No I don't. Maybe you are looking at the 7805 voltage regulator.

bgirlrox17 (author)2009-07-06

I love the idea

amplex (author)2009-06-30

i bought 3 off ebay for <$10 less than a year ago. ive had one sitting on a breadboard for 8 months and still havent put it on perfboard, even though this is a really cool bendable 8bit modulator =( maybe ill finally do it today

sourcery (author)2009-06-25

Maybe you could download DIY Layout Creator and draw a nice circuit diagram for this circuit. It would be easier to follow instructions that way ;)

randofo (author)sourcery2009-06-25

I normally include schematics, but didn't see much point in redrawing something that could be found on the data sheet. There are only a few minor changes which are easy to figure out (such as the SPDT toggle switch between the mic and audio in and the audio out jack instead of the amplifier stage).

sourcery (author)randofo2009-06-26

Ok, it was just a suggestion... I have started to use the program (DIY Layout Creator), and it is quite useful for experiment board projects :) Now I just need to find the HT8950 chip in Sweden :)

Roland54 (author)sourcery2009-06-28

If you look on the Internet, you can find the suppliers but there are also some alternatives mentioned like from Yamaha.

kicker109 (author)2009-06-25

AWESOME 'ible, can you get a different voice to come out... e.g. the voice that kidnappers use (im not a kidnapper)

randofo (author)kicker1092009-06-25

So long as you are not a kidnapper, then, yes. Yes, you can.

kicker109 (author)randofo2009-06-27

How could i do that?

randofo (author)kicker1092009-06-27

Shift the pitch down rather than up.

frodobot (author)2009-06-25

is that .cdr download a circuit diagram? If it isn't, could you post one please because it is quite hard to see where components go.

randofo (author)frodobot2009-06-25

Check the link to the data sheet that I post on that step.

About This Instructable




Bio: My name is Randy and I am a Community Manager in these here parts. In a previously life I had founded and run the Instructables ... More »
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