AM1006 Low Pass Filter

OVERVIEW This 12HP module is a re-imagining of the ARP 1006 low-pass filter which was built around a traditional “Moog” transistor ladder. It has a cutoff range between 16Hz - 16kHz and goes into self oscillation from 200Hz upwards. The 1006 first appeared in the ARP 2500 synthesizer in 1970, as part of a combined filter and VCA module.

We have separated out the filter from the 1005 original, so we can provide the maximum number of signal and CV inputs, just like the original which used matrix switches to engage multiple sound and CV sources.

DESCRIPTION The AM1006F has been carefully engineered to replicate the original filter as closely as possible:

• Large number of inputs (3x audio, 4x CV), to mirror the matrix switch capability
• 5% carbon resistors in all inputs, to mirror the variations in the original
• Ceramic disk capacitors (THD) in the transistor ladder, as per the original
• 680nF film capacitor for DC coupling the filter output, as per the original
• A fast slew rate BJT Op Amp on the output, as per the original
• V/OCT trimmer added for precise frequency tracking
• ARP 2500 control knobs with coloured spun aluminium inlays (Rogan RB-67)
• Black and silver phenolic control knob for frequency cutoff
• Bourns PTL20 LED slide pots with subtle green LED's for CV1 and CV2 depth
• Careful translation to 12V power to retain 200Hz self oscillation

The AM1006F has the original warm saturated ARP transistor ladder sound, coupled with an amazing alumnum printed front panel design. 

CONNECTIONS There are three 3.5 mm jack sockets on the base of the anodised aluminium front panel:

• IN 1, 2 & 3 - audio signal inputs with individual level control
• CV 1, 2, 3 & 4 - 1V/octave control voltage inputs for filter cutoff
• OUTPUT - audio signal output

There are high quality Alpha rotary potentiometers for adjusting frequncy cutoff, resonance and the three input levels, along with Bourns LED slide potentiometers for frequency modulation from CV 1 and CV2 inputs.

The module comes with a set of M3 mounting screws and washers, and a standard 10 to 16-way Doepfer power cable.

PRODUCTION STATUS: IN DEVELOPMENT