Picture of the Dannysound MML Filter module which has the same layout as the Timbre module. It has a 6 HP anodized grey metal panel with blue print. From the top going from left to right it has a trimmer pot for audio input level and an output socket. Underneath are 2 sockets for audio input and resonance CV input. Below that is a skirted black Rogan knob for frequency in the centre with an un-skirted knob to lower left for resonance amount and a push switch to lower right, with 3 LEDs above for low, band or high pass. Under that are 2 controls for CV 1 and CV 2 amount with LED indicators and jack socket inputs.

The Multi-Mode Ladder (MML) Filter is a twist on the classic transistor ladder low pass filter by Dr. Robert A. Moog. This filter updates the classic 4-pole ladder design to provide Band Pass and High Pass filter responses as well as the traditional Low Pass filter, this module also adds CV control over the resonance as well as two frequency CV inputs.

The circuit features a fully discrete transistor design with an op-amp buffered output, this allows soft saturation of the input signal to get the classic overdriven tones of the ladder filter. A bass compensation circuit has been included to retain the bass response in Low Pass mode when the resonance is increased. The bass compensation also helps to improve the response of the High Pass filter. The bass compensation can be removed if the user wishes to have a more classic response (see mods section in build doc).


· Low Pass, Band Pass and High Pass modes.

· CV controlled resonance.

· Added low frequency compensation.

· Soft saturation of input.

· 2 x frequency CV inputs.

6 HP

+12V = 50mA

-12V = 39mA

build documents



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