[chuck-users] help understanding lisa

[eduard aylon]

Hello list,

I am trying to build a granular patch with lisa, but for some reason I  
am getting clicks every time lisa repeats the buffer. Maybe it has to  
do with lisa's duration? Hope someone can explain me what I am doing  
wrong. Following I attach two examples one uses lisa the other uses an  
array. The one that runs with lisa has clicks, the other sounds  
pristine, why? (even if rampup and rampdown were set for lisa). The  
strange thing is that if recorded to file and checked with an audio  
editor I can't see any strange artifacts in the waveform.

thanks for any help,

eduard

// the patch that uses lisa:

LiSa lisa => dac;
1024 => int size;
size::samp => lisa.duration;

for (int i; i < size; i++)
{
   lisa.valueAt(Math.sin(2.0*pi*60*i/size), i::samp);
}

1 => lisa.play;
while(true)
{
   lisa.rampUp(10::samp);
   lisa.duration() - 20::samp => now;
   lisa.rampDown(10::samp);
}



// the other patch with a simple buffer:

Impulse imp => dac;
1024 => int size;
float buffer[size];
size - 1 => int bitmask;

for (int i; i < size; i++)
{
   Math.sin(2.0*pi*60*i/size) => buffer[i];
}

0 => int pos;

while(true)
{
   buffer[pos&bitmask] => imp.next;
   pos++;
   1::samp => now;
}