(
SynthDef(\bpf_brown, {
	var sig, env, rq = 0.005;
	env = Env([0, 1, 0], [\attack.kr(0.02), \release.kr(2)], [1, -2]).kr(2);
	sig = BrownNoise.ar(0.8);
	sig = BPF.ar(sig, \freq.kr(800), rq, 1 / rq.sqrt);
	sig = Pan2.ar(sig, \pan.kr(0), \amp.kr(1)) * env;
	sig = Limiter.ar(sig);
	Out.ar(\out.kr(0), sig);
}).add;

)

(instrument: \bpf_brown, freq: [430, 500, 625].choose, attack: 0, release: 3, amp: 0.6).play;