Renardo's `lpf` and `hpf` attributes apply per-note low-pass and high-pass filters directly on players

Players in Renardo expose lpf (low-pass filter cutoff in Hz) and hpf (high-pass filter cutoff in Hz) as playback attributes, implemented as SuperCollider RLPF/RHPF SynthDef effects. Setting lpf=500 cuts frequencies above 500 Hz per note. Both attributes accept patterns and TimeVars, enabling filter sweeps: lpf=linvar([500, 5000], 8) creates a slow opening filter. The resonance (Q factor) is controlled via lpr and hpr (default 1 = gentle). Combining hpf+lpf creates a bandpass effect. This is a fast way to shape timbre without needing SuperCollider knowledge.

Examples

p1 >> pluck([0,2,4,7], lpf=800)                # only lows pass
p1 >> pluck([0,2,4,7], lpf=linvar([500, 5000], 8))  # filter sweep
p1 >> pluck([0,2,4,7], lpf=2000, hpf=400)     # bandpass zone

Assessment

Describe aurally what happens when you set lpf=200 on a synth. Then set up a filter that sweeps from 200Hz to 4000Hz over 16 beats.