biquad~ Digital filter specified by coefficients biquad~ implements a two-pole, two-zero filter using the following equation : y[n] = a0 * x[n] + a1 * x[n-1] + a2 * x[n-2] - b1 * y[n-1] - b2 * y[n-2]	from the library : MSP Format : External Environment : msp commercial Max 4.x http://www.cycling74.com