Null-A

Null-A2 is an all-in-one analogue synth packed into 42 HP, with no MIDI, microprocessor or software: two VCOs, a state variable VCF, a ladder VCF, a VC delay, three VCAs, two LFOs, a mixer with a headphone amp, a four-stage sequencer, a clock divider, a sample and hold and a Sloth chaos generator. Several presets run between the switches of the jacks, mostly to save a few patch cables; patching into either jack disconnects a preset. The interesting one mixes the sequencer, the Sloth chaos and LFO 2's triangle into the S&H's sample input, so it continually generates stepped and smooth (there is a SLEW pot) CVs, different from but related to everything else going on. The clock divider gives /2, /8, /32 and /128. The sequencer has four stages; its direction control makes it count forwards and backwards for more complex sequences, the X output giving stages 1 to 4 while Y gives 4 to 1. The VC delay makes reverb-like sounds, or all sorts of unexpected zipper noises and effects with TIME and FEEDBACK turned high. The third VCA is built into the ladder VCF's input: with nothing patched into CV VCA it is always on. The Sloth chaos is a very slow CV generator to liven up a patch; it cannot be controlled. Black and gold panels are available at no extra cost.

Key features

• Two VCOs (FREQ, FINE, PW, CV; CV, PWM or SYNC in; TRI and PULS out)
• A state variable VCF (BP and LP out) and a ladder VCF with its built-in VCA
• A VC delay (TIME, FEEDBACK, CV), two VCAs, a two-input mixer with a headphone output
• LFO 1 with S&H (stepped and slewed outputs), an ADSR, a four-stage sequencer (X and Y outputs), LFO 2 and a clock divider (/2 to /128)
• A Sloth chaos generator (OUT X and Y); four LEDs
• Eight presets through the jacks' switches
• 42 HP; +12 V 135 mA, -12 V 90 mA (product page); Nonlinearcircuits publishes no depth or assembled price