Next Rez30 Filter (MAM RS3) 3 Band Pass Resonant Filter

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"This is same unit as MAM RS3 but under different label. No longer made these are rare and a wonderful filter for your electronic music. You set the centers of 3 resonant frequencies and then sweep around them for beautiful swells and sweeps under control of the internal LFO or outboard CV control...

This is MONO in but STEREO out here's a good description -

Controls

Stereo Pan
The RS3 gets it's "mono in, stereo out" designation from Filter 1 and Filter 3 being panable from hard left to hard right. With the control fully counterclockwise, Filter 1 is panned hard left, and Filter 3 is panned hard right. Moving the control to the center places all filters "right up the middle" basically making the unit mono, and then continuing to full clockwise reverse the position of Filter 1 and 3.
Refering back to Mode 3 of the LFO modulation, note that the modulation of Filter 1 and 3 comes from different sources. This is where you will get the greatest stereo effect from the RS3, and this is where the "Jarre Strings" sound lives.

This control also has an effect over how the RS3 can create a stereo spread when using the Envelope Follower. Again, Filter 1 and 3 are panable across the stereo field, and with the three follower channels each driving a separate filter, there is magic to be had.

Resonance
Controls the resonance of the filters.
Volume
Controls the output volume.
Bypass
Switches between the dry and effected signals.
Bandpass 1
Controls the frequency of filter 1.
Bandpass 2
Controls the frequency of filter 2.
Bandpass 3
Controls the frequency of filter 3.
LFO Rate
Controls the speed of the LFO.
LFO Depth
Controls the depth of the LFO sweeps.
LFO Mode 1/2/3
Mode 1: LFO 1+ to BPF 1, LFO 1+ to BPF 2, LFO 1+ to BPF 3
Mode 2: LFO 1+ to BPF 1, LFO 2 to BPF 2, LFO 1+ to BPF 3
Mode 3: LFO 1+ to BPF 1, LFO 1- to BPF 2, LFO 2 to BPF 3
Env Depth
This is a classic envelope follower which allows for sweeping the pass frequency of the filters. But, there's a twist. The envelope follower does some frequency separation at three ranges, "Low", "Mid", and "High", with a separate follower circuit at the output of each of these "channels".
Env Decay
Controls the decay of the envelope
Env Polarity +/-
The polarity of the signal from the envelope follower is switchable from Postive to Negative allowing for classic Down sweeps, as well as Up sweeps, of the filters.
Man/Ext Modulation Depth
When something is plugged into the External jack, the Manual control becomes an polarized attenuator for the signal. In the Middle position, the external signal will have no effect. Moving clockwise from center will cause the external signal to sweep the pass frequency up, while moving counterclockwise from center will cause a sweep down."