After Later Audio - Razor (Blades)

Razor by After Later Audio is a replica of Mutable Instruments' highly flexible dual-filter Blades.

Razor is a fully analog 12dB/octave filter module. The distortion circuit at the beginning of the signal path can be used up to wave folding and is available for both channels. The flexible routing allows the two filters and distortion to be used in parallel or in series, or in a mix of both. Similarly, the filter type can be smoothly crossfaded from low-pass to high-pass. Single outputs and a mixed output are handy for example to fan a mono signal into a stereo signal with different filtering/distortion or to bundle a stereo signal into a mono signal. On the subject of CV control, each parameter has a CV input in addition to attenuators. The blending of filter types, the degree of resonance as well as the amount of distortion can be animated dramatically. Since the filters can be brought to self-oscillation, Razor can be used as a dual oscillator with FM and AM functions.

Razor uses the original "hard to find" opamps, but the V2164M is replaced by the AS2164D.  All After Later Audio products use AS2164D and there should be no measurable difference in behavior.

Features:

• Fully analog, based on the quad VCA chip AS2164D
• Frequency control range: 8Hz to 18kHz
• DC-coupled audio inputs
• All CV inputs handle audio rate modulation
• Clean 2-pole (12dB/octave) state-variable design
• CV-controlled filter behavior, continuously adjustable between lowpass, bandpass and highpass
• CV inputs with attenuators for cutoff and resonance
• Frequency CV input calibrated to 1V/oct
• Clean self-oscillation over the whole audio range, down to very low frequencies, with constant amplitude
• The modulation of the filter response corresponds to the modulation of the phase of the sound produced by self-oscillation