Category: haskell

Canntaireachd for sinewaves

An early sketch of a system of vocables for describing manipulations of a sine wave.

The text is a bit small there, it’s better in the original avi version.

Vowels give pitch, and consonants give movements between pitches.

Inspired by the notation of canntaireachd. Made with hsc (Haskell client for scsynth). As ever, code available under GPL
on application.

I’m not sure where I’m going with this. It’s nice to describe a sound in this way but to use it in music the sound has to change over time otherwise it gets repetitive and therefore boring in many situations. I think I either have to develop ways of manipulating these strings programmatically, or ways of manipulating how they are interpreted. Both approaches would involve livecoding of course…

Haskell supercollider tutorial

Rohan Drape has made a nice tutorial to getting his “Hsc” Haskell bindings to SuperCollider installed and integrated with emacs. It’s available here (link updated). This is exactly what I needed, I’m hoping to get started with some simple physical model synthesis this coming week.

Programming in Haskell

Not really a review, just a strong recommendation… Graham Hutton’s Programming in Haskell is published mid January 2007, but Cambridge University Press are shipping already — I got mine just before Christmas and wish I had it earlier… It is by far the best introduction to Haskell I’ve seen, at least for someone new to functional programming such as myself. The chapters on parsing and and IO are a good mark of the book, together clearly yet stealthily introducing monadic programming in an easily digestible form. Well this book has plenty of other aspects I could praise, but like I say this isn’t a review, just go read and enjoy it yourself.

It’s great to read a really clear, concise text book, I could almost feel my brain re-organising itself while I read it. The experience reminded me of reading K & R after some months of confused C hacking, feeling everything clicking into place. That would be over ten years ago now, gah…


Peano curve weaves of whole songs

Some nine months ago I played with weaving images from music, including using a peano curve as a mapping.

I’ve returned to this subject, having many good ideas to explore from recent discussions with Tim Blackwell. We thought rendering some whole songs would work nicely. I didn’t fancy playing with my Java code again so wrote some Haskell, which I’m rather pleased with. The source is available (feedback welcome!). It does the the mapping using seeks on the output file, allowing impressive memory efficiency via Haskell’s lazy evaluation.

Some examples of some indie synth pop, disco, minimal techno (*3) and industrial gabba below, click on the images for the full versions but beware, they are rather large, around 5M each. Mouseover for the original track names.

Boy From School - Hot Chip At Last I Am Free - Chic Ping Pong - Plastikman Ping Pong - Plastikman (different curve)
Ping Pong - Plastikman (with some colours) Unborn Baby - Venetian Snares and Speedranch

BP2-like polymetric syntax

Another experiment with haskell, rather hastily screencasted for your pleasure:

It’s using haskell’s Parsec module to parse the syntax, and sending the sound events to supercollider for rendering.

This is a work in progress, but GPLd source available is on request, as is an AVI version if you don’t have flash. All feedback much appreciated.

Haskell music

I’ve settled on using Haskell98 for my MSc project. It’s a very interesting language with excellent parsing libraries as well as full opportunities for playing with EDSLs (embedded domain specific languages). After ten or so years of Perl and C learning a pure functional language has been difficult, and I’m still employing far too much trial and error during debugging without fully understanding everything that’s going on, but it feels great to be learning a language again. That’s good because I guess it’ll take me another ten years to learn it properly.

I’ve experimented with making a simple EDSL already, a short screencast of which the flash-enabled will be able to see below:

(Update: I dug out an avi version for the flash-free)It’s really simple:
n <<+ stream – adds a sound every n measures
n <<- stream – removes a sound every n measures

It’s using Don Stewart’s hs-plugins module for reloading bits of Haskell code on the fly. This is interactive programming, also known as livecoding in certain contexts.

Since then I’ve progressed to a more complex language, which for now I’m parsing (with parsec) rather than embedding. It’s based heavily on Bernard Bel’s excellent Bol Processor 2, as introduced in his paper Rationalizing musical time: syntactic and symbolic-numeric approaches. I performed with that (my Haskell parser, I haven’t actually seen or used BP2 itself) for the first time last night at a fine openlab event. It kind of worked but I need a lot more practice. It was fun to perform from a bunch of ghci command prompts anyway, hopefully a screen cast will follow in the next few days.

In both cases I’m not rendering sound with Haskell, but instead sending messages via OpenSoundControl to control software synths I’ve made in SuperCollider and C. This allows me to send sound trigger messages a bit in advance with timestamps, to iron out the latency.

Once I get something I like I will release it properly under a GPL. Until then I’m happy to share my work in progress on request.