Saturday, 24 August 2013

Bending with Dojo part 3: Slight return

This is the last of three posts about building the string bend calculator and maybe the most interesting to anyone other than me. Part 1 dealt with the basic physics and Part 2 with building the Javascript app. All that's left is to wonder what it all means.

Bending with Dojo part 2: Stretching in the Dojo

Following on from Part 1, I wanted to make an interactive way to explore the mechanics of string bending. A spreadsheet is the simplest way to do that, but it needs users to download a file and open it up with the right program. A web-app only needs a browser and internet access to use, but takes a bit more assembly. To cut down the amount of DIY needed it's common to use a framework. JQuery is probably the most commonly used, but without built-in support for plots, so I went for the slight more complex Dojo.
I tried to make the maths background in Part 1 understandable for a general audience, but this Dojo section is going to have to assume you know a few programming terms. If that doesn't sound like your thing, then maybe you're just looking for the string bend calculator.

Bending with Dojo part 1: Maths rock

One of the distinctive sounds of the guitar is bending notes, pushing or pulling the string sideways across the fretboard to raise its pitch. Santana's Samba Pa Ti and Pink Floyd's Shine On You Crazy Diamond have classic examples, but whether you're listening to BB King or Noel Gallagher it'll show up from time to time.
But guitar strings are steel, they can't stretch that much can they? Some people have trouble believing this and think there must be 'give' somewhere else, but a guitar string is thin and long and really can stretch, so I thought I'd put together a string bend calculator to show how. Using it should be self explanatory, this series of posts is about what's happening under the hood.