Boodler and Sax - Elise Chohan - David Casal

PD + Basic stamp + Boodler

Pure Data is a graphical programming environment very similar to max msp.

"PD" stands for Pure Data and is a graphical Computer Music System written by Miller S. Puckette . It works in a similar way as Max (A Computer Music and MIDI system for the Macintosh from Opcode) or jMax from IRCAM. PD is open source software, it is free for any use and can be downloaded from the internet. PD runs on Win32, IRIX and LINUX platforms. It is easy to extend PD with third-party plug-ins (so-called "externals"). Many collections of externals (so-called "libraries") are already available. "
Iohannes M Zm÷elnig: 2002

The main PD patch grew out of various patches which were purely investigative, and had no other purpose than to try out different options available in this programming environment. This created an evolutionary environment, whereby the patch would change if something could be improved to overcome a problem, whether niggly or important.

The negative side of this is that a lot of material was floating around in patches that wasn't actually being used. We had to decide together just exactly how much output we wanted, as with all the various subpatches in, the work, sounded as it looked: a mess! We decided to strip everything out to make it much clearer. For example my 'keys' subpatch, which is a patch I built to send triggers using the computer keyboard, which has most of the keys connected to bangs and 'send' objects. I use this in lots of my patches as it is an easy way to send triggers, so I completely took it for granted. However, having left it in the patch I gave to David, it caused much confusion until I remembered it was there! Fig 1. shows the patch before it was cleaned up.

Fig. 1


The main patch rests on David's machine, boodler operates on the Powerbook and I made myself a small patch on the laptop to connect my buttons into, and sent the signals using netsend to the main patch. This gave me control over the samplers on the main patch. David then used the soundfiler object to make the samples (stored in arrays) into wav files.

We created large buttons so that I could see when he'd taken the soundfiles: he could also take them without me 'closing' the sampler, so that we both had some artistic control. Then with a question of hand signals we could co-ordinate which of the four tables had not yet been filed. The four soundfiles are then transferred to the Powerbook using ssh keys (128bit encryption tool) and used in boodler. The sound from boodler then comes out of Powerbook.

Streamed sample (ogg vorbis mp3) of Boodler and Sax from combined output.

I am using the second outlet in the fiddle~ object to trigger the samplers (the second outlet from the left sends a bang when it 'hears' an attack. An attack from the saxophone triggers the first sampler, then a second attack triggers the next and so on in looping pattern. The 4 buttons, working through the basic stamp, are used turn the samplers on and off. We also added large colourful bangs to allow me to see which sampler was recording at any time.

Building the box of buttons was really an exercise to see if I could manage it. It was relatively easy, with simple circuitry that didn't require any great soldering skills, and with help from Matt Rogalsky, who had used the basic stamp before, the programming was also fairly straightforward. Now that it all works, I would make some more practical arrangements to make the system more comfortable and intuitive. First of all I would find some very lightweight, loose push-to-make buttons and arrange them on the saxophone itself, with a 4-in-one cable to keep it tidy. I would also find a way to run the midi from the basic stamp straight into the linux machine that David uses, to cut out the extra laptop. In a performance environment, it would also be fun to project the patch onto a screen so that everyone, including me, could see it clearly, and try to follow the samplers.

I think the main problem when the buttons were built was deciding on their use, as PD like Max MSP is so versatile as to give the user no prompting for ideas. This harks back to the old argument that the smarter the technology, the bigger the capacity to make dull music, if more attention and time is spent on the technical aspects of the music-making, than the actual musical output itself.

This collaboration was a good middle-ground for two-people to work together. David and I both had some idea of what each other were up to, but had both mostly finalised our half before putting them together. PD can be a frustrating environment to work in, so to get the early hassles and problems out of the way separately, was a great help. On coming together, we made decisions on which parts of the patch to keep (as mentioned above) and then on the musical aspects: the choice of pre-recorded samples, and the shape of individual motives and the work as a whole.