[linux-audio-dev] Synth APIs, pitch control

Hi everybody. I've been reading this list for a week. Thought I'd "pitch" in here because I'm also writing a softstudio; it's pretty far already and the first public release is scheduled Q1/2003. First, I don't understand why you want to design a "synth API". If you want to play a note, why not instantiate a DSP network that does the job, connect it to the main network (where system audio outs reside), run it for a while and then destroy it? That is what events are in my system - timed modifications to the DSP network. On the issue of pitch: if I understood why you want a synth API I would prefer 1.0/octave because it carries less cultural connotations. In my system (it doesn't have a name yet but let's call it MONKEY so I won't have to use the refrain "my system") you just give the frequency in Hz, there is absolutely no concept of pitch. However, if you want, you can define functions like C x = exp((x - 9/12) * log(2)) * middleA, where middleA is another function that takes no parameters. Then you can give pitch as "C 4" (i.e. C in octave 4), for instance. The expression is evaluated and when the event (= modification to DSP network) is instantiated it becomes an input to it, constant if it is constant, linearly interpolated at a specified rate otherwise. I should explain more about MONKEY for this to make much sense but maybe later. Anyway, the question I'm most interested is: why a synth API? -- Sami Perttu "Flower chase the sunshine" Sami.Perttu(a)hiit.fi http://www.cs.helsinki.fi/u/perttu