Latigid on and shakti's suggestions echo my own. I have and use both the Sherman FB II and the Electrix Filter factory with the Voyager.mosaiclive wrote:Is there a multi-mode filter you, or anyone else, can recommend?
Electrix went out of business a while back. The company has been re-launched several times, but I don't know if they are currently producing any hardware (they do [or did] have a software product available). You can pick up a Filter Factory used for maybe $100 or so. It has two, 2-pole multi-mode filters in stereo or a single 4-pole multi-mode filter in mono. There are two CV inputs to control the cutoff of each filter, but no other CV control is possible. It's built like a tank and the operation is pretty straightforward.
The Sherman FB is a beast. It offers similar filters like the Electrix, but has WAY more CV control options, and includes ADSR and AD envelope generators and a VCA. You can use the LFO and ADSR outputs as separate CVs for outboard control of other devices like the Voyager. The Sherman filters aren't isn't as clean as the Electrix (in fact, they're noisier and quirkier), and the Sherman is a good bit more expensive, but it's a nice piece.
There also the Frostwave Resonator. Check out Frostwave.com for more info on this one.
Other possibilities:
A few years ago, Alesis had a product line called Mod Effects that included a box called a Philtre. This was a digital Multi-Mode filter (LP. HP, BP, and Notch) that offered some unique modulation options. That product line went nowhere, and dealers blew out the remaining stock for $25 each.
Akai made a filter called the MFC-42. You can check it out under the 'Legacy' Products tab on the Akaipro.com web site.
Either of these two products might show up on eBay periodically.
And then, of course, there are the modules from MOTM, Wiard, Synthesizers.com, etc., but these aren't stand-alone products.