// I created a new synthdef, that is a sawtooth wave which sends signals pass a bandpass filter. I also included an envolope generator, so I have more control to shape the sound.



(
SynthDef(\bpfsaw, {
		arg atk=6, sus=0, rel=4, c1=1, c2=(-1),
		freq=400, detune=0.3, pan=1, cfhzmin=0.1, cfhzmax=0.3,
		cfmin=600, cfmax=2000, rqmin=0.1, rqmax=0.2,
		lsf=200, ldb=0, amp=1, out=0;
		var sig, env;
		env = EnvGen.kr(Env([0,1,1,0],[atk,sus,rel],[c1,0,c2]),doneAction:2);
		sig = Saw.ar(freq * {LFNoise1.kr(0.2,detune).midiratio});
		sig = BPF.ar(
			sig,
			{LFNoise1.kr(
				LFNoise1.kr(4).exprange(cfhzmin,cfhzmax!2)
			).exprange(cfmin,cfmax)!2},
			{LFNoise1.kr(0.1).exprange(rqmin,rqmax)}!2
		);
		sig = BLowShelf.ar(sig, lsf, 0.5, ldb);
		sig = Balance2.ar(sig[0], sig[1], pan);
		sig = sig * env * amp;
		Out.ar(out, sig);
}).add;
)



// After cleaning up and adjusting the synthdef, I have created a Pbind for the band pass filter sawtooth synth to play. I've programmed an array pitches with an array of pitches, resulting in a chord progression. Randomising patterns, such as Pwhite, Pexprand, have been added to make the sound less predictable. The order in which the chords are played is generated by a pxrand function, which choose from the list randomly, but never repeats the same item twice in immediate succession.

//Notably, the chords used here are all-interval tetrachords, all in a transposition that have a 'C' and 'G' in them. The Pbind has also been modified in its parameters to achieve a customised quality of sound.



(
~chords = Pbind(
			\instrument, \bpfsaw,
			\dur, Pwhite(4.5,7.0),
	\amp, 0.2,
	\attack, Pwhite(2.0, 2.5,inf),
	\legato, 1,
	\cfmin, 100,
	\cfmax, 1500,
	\rqmin, Pexprand(0.01, 0.15, inf),
	\detune, Pexprand (0.01, 0.15, inf),
	\octave, Pwhite(4, 6, inf),
	\rel, Pwhite(6.5, 10, inf),
	\midinote, Pxrand([
		60+[0, 4, 18, 7],
		60+[0, 1, 3, 7],
		60+[0, 10, 18, 7],
		60+[0, 13, 21, 7],
		60+[0, 4, 7, 18],
		60+[0, 7, 15, 18],
		60+[0, 7, 13, 18],
		60+[0, 7, 10, -3],
		60+[0, 7, -1, -8],
			], inf),
		);
);
~chords.play
~chords.stop;



// Since every single chord from the terachord progression above has 'C' and 'G' as pedals (shown as values 0 and 7 in the list above), I wanted to highlight them with a drone in the bass. The drone is made wth a Sine wave, in stereo. I have also made a drone in the middle register.

(
~drone1 = { Pan2.ar(SinOsc.ar([65, 392], mul: Env.linen(1, 10, 360, 0.05).kr(2)))};


~drone1.play;
~drone1.stop;


~drone2 = { Pan2.ar(SinOsc.ar([261, 261], mul: Env.linen(1, 10, 360, 0.05).kr(2)))};

~drone2.play;
~drone2.stop;



//To add to the texture, I have added a very quiet pink noise, in stereo panning, which plays with the spatialisation, and in general adds another level of complexity to the sound.

~noise = {Pan2.ar(in: PinkNoise.ar, pos: SinOsc.kr(0.01), level: 0.03)};
~noise.play;

)

//This is for the recording:
s.makeWindow;
s.record;
s.stopRecording;


//open a volume gui, and set it to minimum before starting the recording.
s.volume.gui;


//play this in order, one at a time, while slowly increasing the volume in the volume gui. Play for as long as needed.

~chords.play
~noise.play
~drone1.play
~done2.play

//to finish, slowly and gradually slide the voulume.gui back to minimum. Once reached silence, play the following codes, or press ctrl+. (control and period).

~chords.stop
~noise.stop
~drone1.stop
~drone2.stop