Arduino – Getting Started

Arduino Midi

When I show off my strange circuit bent devices and synthesizers to musicians and friends of mine I often hear the same thing, “That’s awesome! … But how would you play it live?” This can be a vexing question, Some advanced or complex builds can be played in a live environment but especially as a beginner most of your devices will lack the versatility, reliability or control to be feasible as a live instrument. For this reason many Circuit benders and synth DIY enthusiasts rely on a process of recording and sampling the noises they create and using a sampler or MIDI controller to play them back with a reliable and easy to control interface. This is what I’d like to start exploring today.

Now I want to preface this project by saying that prior to beginning my research and experimentation for this build I had no experience working with the computerized side of music production. I have no background in coding outside of some rudimentary VB and HTML and though with my bands I have gone through the process of recording I have never been responsible for working with recording or mixing programs during this process. But I have an Arduino, and I’ve been led to believe that’s all anyone really needs in this crazy old world.

My goal is to start from the ground up over a series of articles looking at the various parts of this process and developing my own skills with the Arduino, Audio Mixing, MIDI and Recording as always with a strong focus on open source and DIY. Anyone could go out and spend a few grand to set up a recording studio and playback devices but that’s not what I’m about. I want to do it myself, on the cheap and I want to bring you along for the ride. Hopefully by the end we’ll all have a better understanding of how to capture and playback our strange creations.

I’ll still be circuit bending and building DIY synths but keep an eye out for upcoming articles on ways to incorporate the Arduino and software into our music creation process.

 

Speak And Spell 2 – Pitch Bend and Hold

Pitch Bend and HoldAfter a lot of experimentation and some frustration I feel like I am beginning to wrap my head around the Speak and Spell’s operation. This is by far the most complex toy I’ve attempted to bend and as such there has been something of a learning curve as I explored the circuit and began manipulating it. That being said because this is such a popular toy for circuit bending I’ve been able to find a wealth of information to supplement my own experimentation and give me direction as I delve into this project. Today I’ll take you through the addition of a pitch bend up knob and a hold switch to my Speak and Spell.

Pitch Bend

Speak and Spell Pitch BendFor the pitch up bend I actually used three points, I initially found and started experimenting with the pitch bend using the two points on the board above (The 2nd and 4th pins from the right on the synthesizer chip) but found I was able to get a greater range by connecting the third lug on the potentiometer through a resistor to the point shown on the smaller board on the right side. I used a 100K pot and a 15K resistor though I recommend experimenting with different values until you find what works best for you.

Hold

wp-1467656667322.jpgHold and loop functions can be some of the most fun bends on any device as the allow you to create a constant repeating noise from the device which you can modify or play with in all kinds of ways and from my research into the speak and spell I understand it has a number of these type of bends available. Above is shown the first of these bends I was able to locate. If the switch is flipped while the device is making a noise it will continue to make that noise until it is flipped back down. You can then modify the noise output using the pitch bend.

Voltage Divider Tool

Voltage Divider Test Tool Today while trying to sort out the buffers on a voltage divider for one of my circuit bending projects I grew frustrated with the ever growing pile of alligator clips and random resistors/potentiometers piling up on my desk as I experimented with different values. To help alleviate this chaos I spent the last half hour or so putting together a basic tool to help simplify the process.

What this tool allows you to do is attach your voltage in (Vin) to the left screw using an alligator clip. Next attach the center screw to the point the divided voltage is going. Finally you can connect the rightmost screw to ground (Or some other lower reference voltage). You can then adjust the knobs on either side to find the approximate buffer needed for either side of the voltage divider to give you maximum play from the potentiometer you install on your project. This device can also be used as a basic bend tester by attaching your two bend points to the center screw and one of the outside ones to test different resistance values with the bend.

Voltage Divider Testing

You can also play with the potentiometer values or use additional potentiometers to give you an even wider range of values. I would have liked to include a 1 or 2 meg pot and a 10K pot to each side had I had them on hand to give the tool more versatility.

Voltage DividerAbove you can see the schematic for this tool, as you can see it is a fairly simple build. The connectors at the bottom represent the screws for attaching clips on the final project. Please note if you prefer you can use binding posts or banana jacks in place of the screws depending on what is most convenient for you.

Divider WiringHere is the final wiring of the tool

Happy Canada Day

Happy Canada day to my Canadian readers, I will be away over the long weekend but will resume regular updates when I return next week.