Tag Archives: audio

Play your emotional state with Social Vibes and twitter

via Arduino Blog


Social Vibes’ is a Masters Degree (MSc.) project, in Interactive Media by Cian McLysaght, at the University of Limerick, Ireland. They shared with us their project, running on Arduino Uno, composed by a physical artifact designed and created specifically for an installation adopting the fundamental sound mechanisms used in a vibraphone, know also as a ‘Vibe’:

The instrument consists of twelve musical tones of different pitches. The music created on the instrument is derived from a continuous stream of input via multiple users on Twitter and the explicit interaction from Twitter users, tweeting the instrument directly to the project’s, “@vibe_experiment” Twitter account. Data associated with the emotional status of Twitter users, is mined from the Twitter network via Twitter’s open source, application programming interface (API).

For example if a user tweets “The sun is out, I’m happy”, the code I’ve written will strip out key words and strings associated with the user’s emotional state, within the tweets, ie “I’m happy”, and translate this to a musical notation. Mining Twitter’s API, allows a continuous stream of data. These emotional states are then mapped to specific notes on the physical musical instrument, located in a public space. The tempo of the musical expression will be entirely based upon the speed and volume of the incoming tweets on the Twitter API.

Twitter users who are both followers and non followers of the musical instrument’s Twitter account (@vibe_experiment) can tweet directly to the instrument and this direct interaction will be given precedence, allowing user’s who tweet directly to have their emotional state ‘played’. This allows users to hijack or take over the instrument and experiment with it in a playful manner, but also allows those with musical knowledge the potential to compose simple musical arrangements. When users are not tweeting the instrument directly, then the instrument will revert to mining the Twitter API.

To entice users to interact and observe the action of the instrument there is a live streaming broadcast of the instrument via Twitcam on the Vibe’s Twitter account. This is a live streaming broadcast of the instrument via Twitcam on the @vibe_experiment account. Twitcam, is Twitter’s built in live-streaming platform. This simply requires a webcam and a valid Twitter account.

The instrument constantly tweets back updates to it’s own Twitter account to not only inform people of the general status but also to engage users to interact directly with the ‘Vibe’.

Fifty speakers for an interactive sound sculpture

via Arduino Blog


Hive (2.0) is the second iteration of an interactive sound sculpture consisting of fifty speakers and seven audio channels. The sensors detect the proximity of people and Arduino manipulates audio according to it.


It was created by Hopkins Duffield, a Toronto-based collaborative duo exploring ways to combine both new and familiar mediums with artistically technological practices. In this work they used Arduino Uno together with Max 6 / Max For Live.
Check the video to listen to the sculpture:

Sugarcube, a grid based music controller with accelerometer

via Arduino Blog



Once again Amanda Ghassaei sent a cool project she’s been working on lately as an extension of the work she’s been doing on the monome project. Sugarcube is an open source, grid-based, standalone MIDI instrument  self-contained and relatively cheap to make. It communicates via a MIDI output with other electronic MIDI instruments and software environments like Ableton and MaxMSP.

An Arduino Uno generates all of its MIDI data and drives LEDS, buttons, a 2 axis gyroscope, a 3 axis accelerometer,  two potentiometers, and the whole device is powered by a lithium-polymer battery making it pretty portable.

She published detailed  documentation on Instructables to make one yourself   and shared a bunch of videos to discover its main features:

Basically this project is:

A portable, Arduino-powered, grid-based MIDI controller that boots up into a variety of apps to do lots of things with sound. The controller has 16 backlit buttons, used as both inputs and outputs to give the controller some visual feedback. 2 potentiometers give analog control, depending on the app the pots are assigned to tempo, MIDI velocity, pitch, and scrolling (making the avaible grid space larger than 4×4). An x/y accelerometer and an x/y gyroscope add some playful, gestural control to the device; most of the apps implement a “shake to erase” control and several respond to tilt in various ways.

It boots up into 7 different apps, though it has the potential to boot up into 16 total. This device is primarily a MIDI controller, but I’ve also written an app that allows you to pull the button and analog data into MaxMSP and to control audio.

With this project, I was interested in making a device that was a little more self-contained and relatively cheap to make (lots of buttons = lots of $). In keeping more with the concept of the tenori-on, this controller does all its app processing itself, it does not rely on a computer to process button presses/analog controls into MIDI. This means you can plug it directly into a synth or any device that understands MIDI and you’re good to go, no computer required. It runs off a beefy LiPo battery that keeps it running for days on a charge, so it’s fairly portable as well. In keeping with the monome side of things, it’s totally open source and can be adapted to your particular audio setup/needs. All the Arduino code is up on github, along with a MaxMSP patch that decodes data from the controller into something usable in Max.

sugarcube  Arduino

Graphic equaliser

via Raspberry Pi

Our good friends at Adafruit put this project on their Learning System earlier this month. It’s a beaut: you’ll learn something making it, and it looks fantastic when set up. Before we get into the nitty gritty, here’s some video:

This graphic equaliser (a spectrum analys/zer if you’re from the USA) is made from a RGB led strip, with everything down to the audio processing run on the Pi. Everything you see in the video is happening in real time. The setup runs Python, and is based on LightShowPi (which was originally designed to orchestrate Christmas lights), so you’ll be able add LightShowPi features like SMS control from your phone if you’re an advanced user.

Some soldering is required – but soldering is easy, and this is a good project to earn your soldering wings on if you haven’t already. There’s the usual full and helpful tutorial over at Adafruit, along with tips, a parts list, code and all that good stuff. I wish I’d had one of these for my student bedroom. Imagine the parties!

Arduino Yún with sound the supereasy way

via Arduino Blog

Arduino Yún



During Codemotion Milano Stefano had a talk with Federico Vanzati from Officine Arduino on how to use a supercheap USB Audio card with Arduino Yún and test the full audio capabilities with zero effort, external libraries or mp3 shields.

After some days he came out with a quick tutorial that you can check out here (includes code!).



RaspyFi – a distro for music lovers

via Raspberry Pi

RaspyFi was brought to our attention a few days ago: it’s a distro designed especially for those with big media libraries who are using their Pis to listen to music. If you’re one of those people (I am, and I’m chuffed to bits to find RaspyFi), or an honest-to-god audiophile, you may have noticed that other media centre distros have been built to prioritise video rather than music, and don’t necessarily support all the formats your collection might be made up of; or give you the fine degree of control you want over volume and playback. And if you want to stream music wirelessly to other devices on your network, you’ll have to do a little more work with a traditional Raspberry Pi media centre (I can’t believe I’m saying “traditional” about a device that’s only been on the market for 18 months) to get everything working.

So RaspyFi has been engineered to address those issues. Apple AirPlay works out of the box, so you can stream to other devices without any extra work. The distro supports a large number of external USB DACs (there is a pleasingly lengthy list on the project website) and asynchronous playback, so you can use your other amplifiers and DACs instead of the one that’s onboard the Pi – which, let’s face it, wasn’t built for audiophiles.

The UI is really slick, and offers you a web interface you can use to control all your devices, so you can get to local or streamed content from your desktop, phone or tablet. I’ve been enjoying it so far: it’s intuitive, I can play music on any networked device with a web interface without having to install anything, and AirPlay just works - which is very pleasing.

Have a look for yourself. You can download RaspyFi (currently v1.0) from the project website. Documentation, help and tutorials are all available too – let us know what you think!

Building an audio box out of thrown away boards

via Hack a Day» hardware

The last time [Mark] was at the scrap yard, he managed to find the analogue input and output cards of an old Akai DR8 studio hard drive recorder. These cards offered great possibilities (8 ADC inputs, 12 DAC outputs) so he repaired them and made a whole audio system out of them.

The repair only involved changing a couple of low dropout regulators. Afterwards, [Mark] interfaced one of his CPLD development boards so he could produce some sine waves and digitize signals generated from a PC based audio test unit. He then made the frame shown in the picture above and switched to an Altera Cyclone IV FPGA. To complete his system, he designed a small board to attach a VGA screen,  and another to use the nRF24L01 wireless module.

Inside the FPGA, [Mark] used a NIOS II soft core processor to orchestrate the complete system and display a nice user interface. He even made another system with an USB host plug to connect MIDI enabled peripherals, allowing him to wirelessly control his creation.

Filed under: hardware

Giving toys an electronic voice

via Hack a Day» hardware


Whether it’s a Furby or Buzz Lightyear’s button that plays, ‘To infinity and beyond’, most digital audio applications inside toys are actually simple affairs. There’s no Arduino and wave shield, and there’s certainly no Raspi streaming audio from the Internet. No, the audio inside most toys are one or two chip devices capable of storing about a minute or so of audio. [makapuf] built an electronic board game for his kids, and in the process decided to add some digital audio. The result is very similar to what you would find in an actual engineered product, and is simple enough to be replicated by just about anyone.

[makapuf]‘s game is based on Game of the Goose, only brought into the modern world with electronic talking dice. An ATtiny2313 was chosen for the microcontroller and an AT45D 4 Megabit Flash module provided the storage for 8 bit/8khz audio.

The electronic portion of the game has a few functions. The first is calling out numbers, which is done by playing recordings of [makapuf] reading, ‘one’, ‘two’, ‘three’, … ‘twelve’, ‘thir-’, ‘teen’ and so on. This data is pumped out over a pin on the ATtiny through a small amplifier and into a speaker. After that, the code is a simple matter of keeping track of where the players are on the board, keeping score, and generating randomish numbers.

It’s an exceptional exercise in engineering, making a quite complicated game with a bare minimum of parts. [makapuf] estimated he spent under $4 in parts, so if you’re looking to add digital audio to a project on the cheap, we can’t imagine doing better.

You can see a video of [makapuf]‘s project after the break.

Filed under: digital audio hacks, hardware, toy hacks

Raspberry Pi, for all your 50s diner needs

via Raspberry Pi

Have you ever been to a cafe or restaurant with 1950s jukebox wallboxes in each booth? Wallboxes were an extension for a jukebox, making it more convenient to select music right from your table. You’d drop a coin in, choose a song from the flipbook behind the glass, chrome and plastics, and the machine would send pulses down a wire to the restaurant’s jukebox, where a stepper would decode the pulses and queue up the song you’d picked. Refurbished wallboxes occasionally pop up in mock-50s diners; you’ll also see them for sale on eBay for anything up to a few hundred quid, and people buy them to add to their jukeboxes, or just as home decoration (I’ve seen one being used as a particularly cumbersome phonebook).

Wallbox in situ

Steve Devlin bought himself a couple of wallboxes a few years ago, meaning to hook them up to an MP3 player. He then switched over to a SONOS wireless media system in his house, and forgot about the wallboxes for a couple of years.

Enter the Pi.

On looking at a Raspberry Pi and a wallbox, Steve had an idea. Why not hook the two up together to make a controller for the SONOS system? The Pi decodes the pulses from the box, and sends the information to the SONOS system. (This approach will work with any UPnP protocol, so you’re not limited to using SONOS.)

Steve’s thinking about further customisation: a strip in the box with Radio 4 on it; some dynamic strips like “songs of the week”, which will play a selection of the week’s most-played tunes; some LEDs to show a binary index of common faults, like the wifi being down, or a song not being found.

There are full instructions and much more information on Steve’s website. We think there’s something really compelling about this mix of old and new; thanks for sharing, Steve!


via coolarduino

More:   Video1   and   Video2

Now my Arduino can precisely measure audio input (VU meter),   and obviously, next thing that comes to mind right after measurements, is regulation or control. There are many different ways how to electronically adjust audio volume or level of AC signal.  I’ll name a few:

  • Specifically design IC, Digital potentiometers.
  • Mechanical potentiometers, driven by servo / motors.
  • Vacuum tubes amplifiers in “variable-mu” configuration.
  • Resistive opto-isolators.

First category (#1) fits nicely for arduino project. But it’s not interesting to me. My apologies to someone, who was searching an example of interface between arduino and digital pot. Other people don’t tolerate semiconductors in audio path ( tube sound lovers ). Third option would make them happy, only (#3) requires high voltage and difficult to accomplish on low hobbyist budget, so I left it out of the scope. Mechanical pot (#2) would be good solution to satisfy Hi-Fi perfectionists and arduino fans. The same time response time of mechanical parts is too slow, verdict – discarded.  (#4) have been in use since 1960s, but would you like your lovely music to be adjusted by highly toxic CdSe / CdS ?  I don’t think so. Wiki says opto-isolators have low THD distortion level, less than 0.1%. Probably true, but apart from technical aspect, there is always psychological, poisonous CdSe affects my perception.

How about variable resistor in it’s simplest form – tungsten wire? Where you can get one? In the electrical bulb. Perfect material for audiophiles – where distortion could get into ? – It’s pure metal ! And here is my design of the “basic cell” – True Analog Audio Volume Control (T.A.A.V.C.)


As you can see, cell consists of 5 bulbs plus 1 resistor. All elements form 2 attenuation stages, basically – voltage dividers with variable resistors. Resistive values of bulbs proportional to temperature, which is easy to control passing DC current through. To make it work with the biggest possible dynamic range, middle bulb is also heated up by current flow from two differential control lines / phases.

 Hardware prototype / Proof of Concept.


Differential Power Amplifier (PA) IC LM4863  is used as DC current source for control lines. Circuitry powered from 5V regulated switching power supply (4A).  Bulbs – clear mini lights, 2.5V, approximately 200 mA. Cold state resistance about 1.2 – 1.5 Ohm, hot state resistance is rising up to 15 Ohm.  Volume regulator could be connected to any audio source with output impedance no more than 32 Ohm, for example, headphones output. For test I used second channel of the PA, that shown in “optional” box on the left side. Second channel is a “nice to have” feature  in stereo version of the project, when both channels would drive two separate TAAVC cells, so using it as a “buffer” amplifier may be not an option.


  Measured attenuation  range of the “basic cell” is  20 dB, or 10 x times.

266c260c 264c

 to be continue…

 Chart, PWM (Voltage) to Attenuation:


 Quite interesting, isn’t it? I was not expecting it’s to be linear, but changing direction surprised me. There is one things, which could explain such abnormality, is that when voltage on the control lines 1 and 2 ( LM4863 outputs ) is approaching power rails, output impedance of the power amplifier is increasing, and consequently, attenuation characteristics of the basic cell deteriorate. It means, that in order to keep attenuation curve gradually declining, more powerful PA necessary. For now, I limited PWM to 0 – 200 range.

I’m thinking, STA540  powered from +12V, and 5 V bulbs would make sense to try next time.  Probably, replacing middle bulb for less current hungry, will increase max attenuation per cell up to 30-35 dB.

 O’K, after I get this data, how could I “straighten it up” for practical use ?  Volume control device, could be linear or logarithmic, but chart doesn’t resemble nether of this. And this is exactly what I need Arduino for.


 If you, by chance, have read this page, than you know how to do this part. Polynomial approximation. Unfortunately,  2-nd degree polynomial I used last time is not enough for VERY non-linear curve like I have. So, I “upgraded” my calibration subroutine (method: LEAST SQUARES) up to 3-rd degree:

void calibrate()
 //Least squares 3-rd degree polynomial coefficient calculation
 float arr[10][5] ={{0},{0}}, err[10] = {0}, coeff[10] = {0};

 err[0] = 10;
 for(uint8_t i = 1; i < 7; i++)
  err[i] = 0;
  for(uint8_t j = 0; j < 10; j++)
   err[i] += pow(level_table[j], i);

 for(uint8_t i = 0; i < 4; i++)
  for(uint8_t j = 0; j < 4; j++)
   arr[i][j] = err[i+j];

 for(uint8_t i = 0; i < 4; i++)
  arr[i][4] = 0;
  for(uint8_t j = 0; j < 10; j++)
   if (i==0) arr[i][4] += calibration[j];
   else arr[i][4] += calibration[j] * pow(level_table[j], i);

 for(uint8_t k = 0; k < 4; k++)
  for(uint8_t i = 0; i < 4; i++)
   if ( i != k )
    for(uint8_t j = (k + 1); j < 5; j++)
     arr[i][j] -= ((arr[i][k] * arr[k][j]) / arr[k][k]);

 union split_float {
 uint16_t tegri[2];
 float loatf;
 } sf; 

 for(uint8_t i = 0; i < 4; i++)
  coeff[i] = ( arr[i][4] / arr[i][i]);
  sf.loatf = coeff[i];
  store_entry(( 2 * i ), sf.tegri[0] );
  store_entry(( 1 + (2 * i)), sf.tegri[1] );

Procedure takes 10 data samples as input, calculates 4 coefficients and stores them in EEPROM memory.

VU meter based on Arduino UNO ( in minimum configuration Arduino and DC offsetting circuit ) should be connected right to T.A.A.V.C. output. Everything works in automatic mode, with results printed on serial monitor for review. Stable AC input is necessary, which easy to get from any PC sound card based signal generator, recorded media file or lab sine-wave generator. Arduino also provides PWM for T.A.A.V.C       via pin D3 (TIMER2 OCR2B).


Link to download Arduino UNO sketch: T.A.A.V.C.

to be continue…audio compressor, .

Last part,

Dynamic Range Compressor.

There are two important parameters defined in the beginning of the sketch:

#define          CMP_THRE                     -10             // Compression Threshold 
#define          CMP_RATE                        4             // Compression Ratio 4 : 1

Threshold and Ratio. I’m not into explaining all bunch of the details about compressors or what for do you need one, rather forward you to this link.  I only want to say, that I didn’t find any evidence that someone ever used electrical bulbs as compressors “engine”. So, this is my idea, and my implementation.

Technical specification of this design is quite modest, having close to 20 dB maximum attenuation and setting ratio to 2:1, threshold couldn’t be set lower than -40 dB. Good news, that for practical use in home environment it’s  really unlikely, that you ‘d need more. It’s also should be enough to solve a problem with annoying TV or Radio commercial / advertisement.

Compare to VU Meter project, I’ve made a few “relaxing” changes to the code, as it appears there are no strict industry standard on Dynamic Range Regulation. I reduce sampling rate down to 10 kHz,  and  split Low Pass Filtering in two sections. One is the same, as in VU Meter, inside sampling interruption subroutine, only with lower time constants. First LPF section is responsible for “shaping” attack and decay timing. Using quite inertial electrical bulbs in the project, reduce importance of this timing. Here attack and release mostly defined  by thermal responsiveness of the bulbs, which isn’t very high. Decreasing software LPF time constants helps to improve sensitivity. Other LPF section included inside LCD drawing function, works to overcome display slowness, suppressing LCD flickering. Other changes from simple VU Meter, is that finally I “scaled” everything correctly,  and “0″ db corresponds exactly to 1.228 V RMS at the input. Threshold level -10 expressed in dB as well. You may see threshold “mark” above the log scale. Indicator “needle” just below it, small 5×2 pixels only, but you can make it bigger if you wish.


I already described calibration procedure, to do it right, you need to connect arduino to output of the TAAVC cell.  Polynomial coefficients and minimum / maximum constants stored in EEPROM, so you don’t have to do this procedure each time after power cycling.  In normal mode arduino getting input measurements from the cell input:


Finished.  I’ll do a video “on demand” -);  If I had time…

Arduino UNO sketch:  Audio Dynamic Range Compressor. (TAAVC part 3).

MakerLab reviews the Arduino Starter Kit

via Arduino Blog

When we released the Arduino Kit, we knew that we are equiping the closet-wannabe-makers to start planning for world domination. Now it has the stamp of approval from MakerLab too!

Make Noise With The New Arduino Kit is a project by Alessandro Contini (@CNTLSN) and Alberto Massa (@nkint)

The above video explores the basic components of the kit and things that a new-maker would want to start with, including a light controlled theramin, and by theramin, I really mean exploring every possibe way to make impressive noises from one simple experiment.

Sounds fun? Do write to us, what you made out of your starter kit. We may feature you next ;)


Media streaming without Air Play

via Raspberry Pi

Just before the New Year, we saw a lot of links in the tech press to a very neat hack using a Raspberry Pi as an Apple AirPlay receiver. The project had so many news stories written about it before I’d spotted it that I didn’t put it on this blog at the time because I thought most of you would have seen it – but do go and have a look if you’re a iTunes person (and have managed to get your head around the new layout of the library in iTunes 11 – my own failure to have got accustomed to it so far makes me worry about brain softening).

If you’re not an iTunes person, and you’re looking for an open alternative, you could do a lot worse than use Stephen Phillips’ UPnP/DLNA streaming method, which uses Android phones as remote controls. Your music lives on a server, and streams to your home speakers via the Pi. You can also play your music by streaming it to any of those phones, whether you’re at home or out gallivanting.

If you already have at least one Android device and some speakers, Stephen reckons that your outlay, including the Pi, should be about £45 – contrast this with the cost of a similar (closed) setup using Sonos hardware (today’s price on Amazon, with a sale on, was £230). Audio quality should be as good as – or even better than, depending on what your home hi-fi setup is like – an off-the-shelf solution using AirPlay, Sonos or Squeezebox, despite coming in at a fifth the price.

This is something I’ve been meaning to set a Pi up at home to do for ages (a little thing called work has got in the way). If you want to make your own streaming setup, Stephen has easy-to-follow instructions on his blog.



via Raspberry Pi

Update, Jan 12: Cargo Cult (whose name is actually Adam Foster) found that a lot of people were very interested in this project. Not least, Radio 4. Who interviewed him for the PM programme this afternoon about his hack. You can hear the programme at the PM website – listen now, because I can’t guarantee how long this will stay up! Adam’s bit starts at 27m00s.

I know several of you are making your own version of this project. Adam’s now blogged all the code you’ll need and very thorough instructions: so you’ve got no excuse for not getting started!

I’ve got a longstanding addiction to BBC Radio 4. It’s my alarm clock, keeps me company in the car, gives me something to shout at, and occasionally furnishes lovely surprises (like New Year’s morning last week, when the Raspberry Pi got a shout out on the Today program, and then Eben’s Dad was on ten minutes later talking about English dialect).

It can be a bit discombobulating trying to listen to Radio 4 online when you’re out of the country – Listen Again isn’t available for a day or so, and if you listen live, nothing is on at the right time. I must be woken by the soft keenings of James Naughtie, or else the day just doesn’t go right. PM must start at 5pm, and always coincides with a cup of tea. The Archers at 7 is a reminder that it’s time to turn off the radio, get out of the study and make dinner. Time-shifting any of these things just makes the day shapeless and wrong. Happily, our forum member Cargo Cult has experienced the same discombobulation. So he’s used a Raspberry Pi to build a time-travelling radio. He says:

Timezones. It’s live radio, but all the timing is wrong. Namely, the written-in-stone Radio 4 schedule must not, under any circumstances, be allowed to become misaligned from the rising and the setting of the sun. How could anything (or anyone) remotely British even think of operating normally if the Friday evening comedy gets broadcast on Friday morning, or if the Book at Bedtime arrives early in the evening? Or heaven forbid, if Woman’s Hour escapes from its usual 10am ghetto?

So, short of removing both the North American continent and the Atlantic Ocean in order to make Seattle a suburb of Plymouth, we’re going to have to take the existing internet radio streaming and add a timezone-busting delay. Oh, and then wrap the whole thing in a suitably middle-class casing complete with a Royal warrant of appointment.Luckily, we moved west of the Prime meridian, so we can get away without using actual time travel.

Cue the Radio-4-Matic.

From the outside, the Radio-4-Matic looks just like the old Roberts radio my Grandma had in her kitchen. It’s had a Pi inserted into its helpless torso. The LW, MW and SW buttons provide line-in audio from the Pi’s analogue audio-out – VHF still operates as a regular radio. And the audio that’s coming from the Pi is BBC Radio 4, time-shifted so that wherever you are, the shipping forecast is on at twelve minutes to one in the morning. Ford’s in his flivver, all’s well with the world.

Cargo Cult hasn’t written a how-to guide yet (he does plan to), but he has an excellent description of what he did with enough pointers in there to allow you to set one up yourself if you’re a relatively seasoned coder. You can read more (and ask questions) in this thread in our forums.

Hacking an old radar gun to interface with a laptop

via Hack a Day» hardware

[Gregory Charvat] decided to see what he could do with this old Police radar gun. It is an X-band device that broadcasts continuous waves and measures the Doppler shift as they echo back. He cracked it open to see if he could interface the output with a computer.

After a little poking around he’s able to get it connected to a 12V feed from his bench supply, and to monitor the output with an oscilloscope. He established that it draws about 0.5A in current he built a companion board which uses AA batteries for power, and provides an audio output which can be plugged into his laptop’s audio-in jack. This technique makes reading the device as easy as recording some audio. From there a bit of simple signal processing lets him graph the incoming measurement.

In the video after the break you’ll see his inspection of the hardware. After making his alterations he takes it into the field, measuring several cars, a few birds, and himself jogging.

Filed under: digital audio hacks, hardware

Pumpkin Pi

via Raspberry Pi

We’re on the hunt for guest posts for a couple of weeks in November. See this post for more details on how to contribute.

There seem to be a lot of Raspberry Pi + pumpkin projects around at the moment. Can’t think why.

Scary bucket

Gordon@Drogon’s Pumpkin Pi (as featured in the MagPi). Gordon had to photograph this in the summer, when pumpkins were not available, so he’s used a sort of Halloween bucket instead. Click the picture for instructions and more bucket photos.

There’s non-pumpkin spooky activity out there too. I love this: it’s a Raspberry Pi, an eight-switch relay, a garage door lifter rod, and a can opener, all hacked together to make a candy dispensing machine so you don’t actually have to interact with any children or open the front door on Halloween.

I love this even more: it’s a Raspberry Pi and a Makey Makey in a box, hooked together to make a Halloween sound box that uses the conductivity of your fingers to trigger events.

And Shawn Wallace at Make has made this, with an Arduino, a Pi, some switches and a recording of the Wilhelm Scream. Visit Make for complete instructions on making your own.

Do you have any Halloween Pi plans? Let us know in the comments.