Admiral Quality has released Naive LPF v0.5, a free, resonant low-pass filter with envelope follower VST effect plug-in for Windows. It has been developed to closely model the way some real world analog circuits work.

Features:

• Cutoff Frequency: Continually variable, from far above the sample rate of your host down to 0 Hz.
• 4 Stages: Selecting the number of Stages adjusts the cutoff slope of the filter. More stages make a steeper slope.
• Resonance: Enhances frequencies near the cutoff by feeding the inverted output signal back into the input. The resonance can be set high enough that this filter will enter self-oscillation and produce very loud signals, even without any input signal present.
• Envelope Follower: Vary the cutoff frequency in response to the dynamics of the input signal, creating "auto-wah" type effects. With Attack and Release controls.
• HPF Mode: Subtracts the low-pass filter's output from the original input, providing a high-pass filter effect.
• Output Saturation: Reduce excessive peaks back below 0 dB.
• 6 input / 6 output channels. Each channel has its own independent filter with envelope follower.