SuperCollider/Schroeder 混響中的聲音設計

圖 14.28：迴圈 Schroeder 混響

首先啟動伺服器，如果你還沒有啟動的話

s.boot;

然後，為了獲得一些源素材，我們將載入 SC 附帶的標準聲音檔案

b = Buffer.read(s, "sounds/a11wlk01-44_1.aiff");
// Hear it raw:
b.play

現在，這段程式碼在一個單獨的合成器中建立混響，並有四條獨立的延遲線相互交叉交叉

(
Ndef(\verb, {	
	var input, output, delrd, sig, deltimes;
	
	// Choose which sort of input you want by (un)commenting these lines:
	input = Pan2.ar(PlayBuf.ar(1, b, loop: 0), -0.5); // buffer playback, panned halfway left
	//input = SoundIn.ar([0,1]); // TAKE CARE of feedback - use headphones
	//input = Dust2.ar([0.1, 0.01]); // Occasional clicks
	
	// Read our 4-channel delayed signals back from the feedback loop
	delrd = LocalIn.ar(4);
	
	// This will be our eventual output, which will also be recirculated
	output = input + delrd[[0,1]];
	
	// Cross-fertilise the four delay lines with each other:
	sig = [output[0]+output[1], output[0]-output[1], delrd[2]+delrd[3], delrd[2]-delrd[3]];
	sig = [sig[0]+sig[2], sig[1]+sig[3], sig[0]-sig[2], sig[1]-sig[3]];
	// Attenutate the delayed signals so they decay:
	sig = sig * [0.4, 0.37, 0.333, 0.3];
	
	// Here we give delay times in milliseconds, convert to seconds,
	// then compensate with ControlDur for the one-block delay
	// which is always introduced when using the LocalIn/Out fdbk loop
	deltimes = [101, 143, 165, 177] * 0.001 - ControlDur.ir;
	
	// Apply the delays and send the signals into the feedback loop
	LocalOut.ar(DelayC.ar(sig, deltimes, deltimes));
	
	// Now let's hear it:
	output
	
}).play
)

這裡還有另一種完成同樣事情的方法，這次使用矩陣來表示延遲流的交叉混合。單個矩陣取代了所有這些加號和減號，因此它是表示混合的一種簡潔方法 - 看看哪種對你來說最易讀。

(
Ndef(\verb, {	
	var input, output, delrd, sig, deltimes;
	
	// Choose which sort of input you want by (un)commenting these lines:
	input = Pan2.ar(PlayBuf.ar(1, b, loop: 0), -0.5); // buffer playback, panned halfway left
	//input = SoundIn.ar([0,1]); // TAKE CARE of feedback - use headphones
	//input = Dust2.ar([0.1, 0.01]); // Occasional clicks
	
	// Read our 4-channel delayed signals back from the feedback loop
	delrd = LocalIn.ar(4);
	
	// This will be our eventual output, which will also be recirculated
	output = input + delrd[[0,1]];
	
	sig = output ++ delrd[[2,3]];
	// Cross-fertilise the four delay lines with each other:
	sig = ([ [1, 1, 1, 1],
	 [1, -1, 1, -1],
	 [1, 1, -1, -1],
	 [1, -1, -1, 1]] * sig).sum;
	// Attenutate the delayed signals so they decay:
	sig = sig * [0.4, 0.37, 0.333, 0.3];
	
	// Here we give delay times in milliseconds, convert to seconds,
	// then compensate with ControlDur for the one-block delay
	// which is always introduced when using the LocalIn/Out fdbk loop
	deltimes = [101, 143, 165, 177] * 0.001 - ControlDur.ir;
	
	// Apply the delays and send the signals into the feedback loop
	LocalOut.ar(DelayC.ar(sig, deltimes, deltimes));
	
	// Now let's hear it:
	output
	
}).play
)

// To stop it:
Ndef(\verb).free;