Here we have another instrument that I built to use for my final piece. It combines a DJ kit toy with an ‘electro’ pen and cycles through samples in a rhythmic way. It uses five samples, and on each iteration of the loop, on of the samples is changed
For example, it might begin with a rhythm of
and then on the next iteration it might change to
and gradually, the rhythm changes into something new.
The way it does this is similar to the way in which a group of church bell ringers alter their patterns in ‘change ringing’ – hence the name – “Church Bell Rhythms”.
Here is one of the instruments I created to use in my final piece. It is made from a toy turtle that plays various nursery rhymes when the buttons are pressed. I added a schmitt trigger (NOT gate) in conjunction with a relay, and also added some switches and potentiometers. This toy has been hacked in the traditional sense and now makes some very unusual sounds.
So I’ve recently been spending some time learning about Arduino. If you don’t know a lot about it, you can find out some basic info at the Arduino website here.
Essentially, it is an interface between any kind of electronic equipment and a computer. You can program some code using the Arduino programming language (which is based on C), then upload this code to the Arduino board and it will be able to perform tasks for you.
Here, I have used a set of relays to create switches that are controlled by the Arduino. I have also taken out the insides of a toy piano keyboard and used these switches to set off the notes on the keyboard.
In this instance, I have programmed it to play twinkle twinkle. Not an exciting use of such technology, but the theory is that I can use this arduino and relay setup to set off any switch on any electronic device, and even perform bends for me at precisely scheduled intervals
Check out the video here:
The reverse of this can also happen. I can set up switches and potentiometers that can be interpreted by the computer in some way or another. I can also use the pulse width modulation (PWM) feature to approximate a variable resistor.
Finally, I did it! After some messing around with my toy yamaha keyboard, it finally seems to be working again. Have a look at my previous post back in November by clicking here for more detail. And, not only is it working, it’s once again making some great sounds. I hard wired in a couple of cables at the spot where I was previously pressing with my fingers to make a connection. This time I added a switch and a resistor, instead, to make it a bit more user friendly. I wasn’t sure whether the value of the resistor would make a difference to the sound made, but apparently not! The first one I tried, I got the same bizarre, random response from the keyboard that I remember from several months ago.
Take a look at the video and see for yourself:
at 2:13 is where it gets really interesting – you’ll notice because I stop to take a drink!
I can honestly say that I have no idea why this is happening. The connection I make affects what appears to be the chip that does the main processing for the keyboard. It seems that messing with the internals of the CPU is a little like giving a person hallucinogenic drugs, which would explain the erratic behaviour.
If you want to hear more, here is another 17 minutes if me playing with this.
I have been working on a while on trying to fix a broken SNES console. Unfortunately it seems that the motherboard is knackered beyond repair, however that didn’t dissuade me from trying to make some cool noises with it. I did a bit of research and discovered where on the motherboard the audio is processed. Using a bit of trial and error more so than technical knowledge, I soldered some connections to the motherboard. I then attached these connections to a toy keyboard, so that I could play the console like an instrument. What’s interesting abut the keyboard is that it is actually touch sensitive: the harder I press the keys, the stronger the connection is. The original toy didn’t use this functionality, and simply used the keys as switches, but it makes for a much more dynamic and fun instrument.
Watch this video to see it in action:
You will notice that half way through I hit the reset button. I have found that this sometimes makes the sounds change a little, especially if you are holding down a note while you do it.
This little circuit is based on an idea from Nicolas Collins’ book “Handmade Electronics”. Essentially he uses a digital inverter (that turns a 1 into a 0 and a 0 into a 1 – AKA a “not” gate) to make a square wave oscillator. I took this simple idea and altered it so that it included two resistors and two switches, so that it would oscillate at different frequencies depending on which switch I pressed. In other words, its an extremely basic keyboard synthesiser (with only two notes, and only one setting). By adding more resistors and switches I could essentially have a whole keyboard full of notes. Why, you ask? Admittedly much better synthesisers and keyboards already exist, but the process is still interesting and helps me to better understand how these things work.
Have a look at the video:
Interestingly, pressing both switches down together makes a third note. This is because the two resistors are now working in parallel with one another, causing a third resistance and therefore a third note. In order to stop this effect I would have have to make one cut out when the other is playing, or have polyphony, both of which would require more complex circuits. Perhaps this could be the next thing to work on.
When I found this toy in the charity shop, I knew at once that I had to have it. It wasn’t just a toy that made sound and would be interesting to listen to and hack; it was also itself a learning tool for electronics. There wasn’t a complicated circuit board that I would have to figure out or guess – all of the parts were clearly labelled and there was no secret to how it worked.
The manual comes with a list of simple electronics circuits that you can build. Unfortunately, a lot of the parts were broken and a lot of the circuits for whatever reason simply didn’t work, however one particular circuit that did work was the “Burglar Alarm” which was essentially just an oscillator that you could switch on and off.
Using the basic burglar alarm setup as a basis, I altered it by switching the resistors and capacitors and making connections between different points in the circuit.
Also, when connecting the audio output, instead of connecting the ground bus, I used objects around the house as a ground. My own body was a particularly strong sound, and the printer created a very interesting noise.
Here’s a video I made of my first proper hack. It’s one of the simplest hacks you can make to any toy, simply changing the clock speed to make it run faster or slower. In this example I have soldered two cables to the circuit board, and the connection is made through the resistance of my body. I am able to vary it by pressing harder and softer on the ends of the wires.
Below is my short explanation on youtube:
Here we have a magic eight ball-style decision making toy that cycles through various options when shook. I have hacked it by making a connection between two points on the circuit board. By using my own body as the clock resistor, I can alter the speed (and therefore pitch) by changing the pressure put by my fingers on the two bare wires. As you can see, if the resistance is too low it will just completely stop. I have also added an off switch, so that I can shut it up.
I didn’t realise it at the time, but I managed to strike gold pretty early on in this project, with a toy yamaha keyboard that I’d had in the house for years. Unfortunately It was broken – when turned on, it just played one note constantly like a siren and wouldn’t shut up. I decided to open it up and have a look.
With careful, close consideration I discovered that I was totally incompetent and probably wouldn’t be able to fix it. But when I experimented with it, I noticed that making a connection between two points not only stopped the siren but caused something much more amazing to happen.
Making this connection had a totally random, bizarre effect, causing the toy to behave erratically. Listen to the audio here:
Unfortunately, for some inexplicable reason, this keyboard now appears to be broken beyond repair. However, I have found another very similar Yamaha Toy Keyboard at the car boot sale that I am yet to open up. I’m hoping that it will have a similar “madness button”.
For the next few months I will be talking a lot about my Project. I spent the first couple of weeks at University coming up with the Project Proposal and finding an appropriate supervisor. For the full project proposal, click here.
For the short version, read on. For the even shorter version, just take a look at this picture –>
Actually, that photo is of a microphone and tape loop setup, but the principle is roughly the same.
Basically I am interested in Chiptune music. This is where the sounds from old video games consoles are used to create modern music. By using Circuit bending techniques (learned primarily from Nicholas Collins’ Handmade Electronic Music and Rheed Ghazala’s Circuit-Bending) I am spending a lot of my time opening up toys and games and making unusual sounds with them. I am also looking into other types of Chiptune how other techniques for creating retro sounds.