I'm sure that many readers of this magazine will agree that there are plug-ins on the market today that can do just about anything imaginable. Even though

I'm sure that many readers of this magazine will agree that there are plug-ins on the market today that can do just about anything imaginable. Even though I fully appreciate and use a wide array of plug-in effects, there is still a big place in my heart (and studio) for some good old-fashioned stompboxes that are so unique and great-sounding that no plug-in will ever touch them. These days, even when about half of my work is recorded and mixed in the box, I still integrate some sort of pedal or outboard piece into the production as a way to make things sound a little different, bigger, weirder — you fill in the blank. Some of my favorites and overall best-sounding are the Moogerfooger pedals that have come from the brain of Bob Moog and his staff; most of these, I own and use on a regular basis. With this in mind, I was especially excited to check out the new Moog Multiple Resonance Filter Array, or MF-105 MuRF as it is officially called.

Like all of the Moogerfooger boxes, the MuRF has a robust build quality. It's made from solid wood with a sheet-metal faceplate and uses the same high-quality knobs and highly responsive LEDs that all of the other models (MF-101 Lowpass Filter, MF-102 Ring Modulator and MF-103 12-Stage Phaser) use. It has two basic functions: It's an 8-band array of resonant bandpass filters combined with a preprogrammed Animation module that generates sequences of envelopes. These sequences modulate the levels of eight resonant bandpass filters, each of which are tuned to fixed frequencies. The levels of each frequency are controlled by eight sliders that give the MuRF the look and feel of a graphic EQ.

You can animate the levels of the eight filters in a total of 24 preset patterns. The rate of the patterns can be set by a knob, an expression pedal or with tap tempo. Several of the performance parameters are voltage-controllable, which allows you to use expression pedals, MIDI-to-CV converters or any other source of control voltages, such as other Moogerfoogers, to “play” your MuRF. As a result, the tactile tweak factor is really high. Rhythmic variations can be created by adjusting the levels of the filters. The Envelope control sets the shape of the modulation, and the Rate knob controls the speed of the selected pattern. Other controls include input drive, output level and wet/dry mix.


The MuRF's Animation module contains eight simple sequencers — one for each filter — each capable of triggering an envelope generator that shapes the volume of the filter. The point that the envelopes are triggered is determined by the pattern selected. The shape of the envelopes is determined by the setting of the Envelope control. It's all based on the vintage sequencers that were typically built so that there were a certain number of steps, or individual components of a pattern. In many vintage or analog sequencers, a sequencer typically had eight or 16 steps available to build a pattern.

On the MuRF, the Envelope control morphs through different envelope shapes as you turn it, creating effects that range from rhythmic to ethereal. The Rate control sets the speed of the pattern. The patterns, selected by the Pattern selector rotary switch in conjunction with the bank slider, have been selected to provide a wide variety of rhythmic and textural effects. There are a total of 24 patterns arranged in two banks of 12 each. For the more visually inclined, the manual also has a graphic description of each of the 24 patterns.

In its simplest form, as the Animation module plays back its corresponding sequencer steps, each step can be programmed to send a trigger signal or not — a step can be passed over like a musical rest. The trigger signals can then be used to trigger envelope generators according to the way each step is programmed, creating a rhythmically reoccurring pattern. If this sounds complicated here, putting the MuRF into action brings it all together.


The MuRF has the same big, sweet sound as the classic Moog synths — it's the Moog sound; there is no other way to put it. Just as a simple filter box, the MuRF is fantastic-sounding. The filters on the MuRF are resonant filters, which means that they boost the signal at the center frequencies of the filters. The eight center frequencies are 200, 300, 450 and 675 Hz and 1, 1.5, 2.2 and 3.4 kHz, and they are tuned so that they don't overlap. The MuRF's filters are fully meant to color the signal a great deal by adding resonances throughout the frequency spectrum, so it's all about adding the goo, so to speak. As far as how the filters sound next to my favorite pedal filter (the Lovetone Meatball), it was a slightly different beast but just as dense and big-sounding.

The real star of this pedal is the groove factor. The Animation component of the box coupled with an amazing envelope circuit makes the MuRF a lethal weapon. The patterns are varied and provide fuel that can be morphed into endless possible bits of material, ranging from tight chunks of four-on-the-floor groove to filterized, oozing space globs. The rate can also be tweaked via the tap pedal, and I was quickly able to get groove patterns to fit into a few different tracks that I had up for testing. It was hard for me to find a way to not to make it work in a track. For a while, I was using a Pioneer CDJ-1000 with some raw drum loops that I had sounding like arpeggiated synth lines coming from a Moog Prodigy.

Another thing I like about the MuRF — and all of the Moogerfooger pedals — is that they have an input gain stage as well as an output gain stage, which allows you to really crank the input gain to get a nice overdrive thing happening. Using the MuRF as a stereo device is great if you want to generate some interesting spatial material. In stereo mode, half of the filters are sent to the Right output, and half are sent to the Left/Mono output.

Bob Moog has been designing circuits for so long and with such beautiful results that any pedal he produces is bound to be interesting, if not amazing. After having my way with this pedal for a couple of weeks, I have to say that the MuRF falls into the amazing category. When it comes to analog filter-based circuitry, this is as good as it gets. Overall, this is a really powerful and great-sounding box.



MF-105 MURF > $449

Pros: Excellent-sounding analog filter array. Selectable patterns. Envelope-based sequencing. Works with virtually any sound source. Synchable to other gear and computer workstations.

Cons: None.