Strange Science Instruments - Stereo Lowpass Filter
"Bob Moog's "transistor ladder" filter is a work of genius. This brilliant design uses a small number of components to achieve the warm and fat sound that has inspired generations of musicians. When designing our F-1: Stereo Lowpass Filter, we researched many filter topologies but ultimately came back to the elegant transistor ladder as our starting point. From there, we added modern touches like linked-stereo (or dual-mono) operation, 12/18/24dB slope/octave selection, and temperature compensation for accurate tracking."
http://www.strangesci.com/f1stereofilter/
This Module is currently available.
$449