This Module is discontinued.
Moog style low pass and band pass filter
The Transistor Superladder voltage controlled filter (VCF) is a reworked Moog style transistor ladder filter. Cut-off frequency and resonance are both voltage controllable. The Transistor Superladder VCF has a variable shape output. It incorporates a feature first seen on the Oakley Orbital prototypes. A single pot allows you to vary the output from one pole low pass to four pole low pass via band pass in the middle.
The Superladder's output is 'Q compensated'. This means that the output volume will not drop significantly when you turn up the resonance pot. This design uses two inbuilt VCAs to achieve voltage controlled resonance without the hassle. At high levels of resonance the Superladder will self-oscillate across most of the audio band and thus can be used as a sinewave voltage controlled oscillator.
The module design uses a discrete transistor core which means it does not clip the signal abruptly but saturates smoothly. This allows the Superladder to sound very different depending on the input signal level. When used with signals below 1.5V peak the Superladder will sound clean and bright. However, take your signal levels above 1.5V peak and it will start to take on a more strident tone particularly at higher levels of resonance. Coupled with the variable slope control, this sensitivity to input level means the Superladder can produce a wonderful array of different tones.
The voltage controlled filter, or VCF, may be built as a 1U filter core or as a complete 3U filter system. In the 1U 'Filter Core' format the module can be used as a filter module on its own. Users need to make use of external mixers to control CV and audio levels going into the filter. In this way, you will be able to have a collection of space saving 1U filter cores that can be used with any generic mixer module. The Oakley Multimix is an ideal choice for a handy mixer module.
