Tiny analog envelope filter pedal that packs a big, vintage-sounding funky punch
By Phil O'Keefe
Malekko's Omicron line of diminutive pedals are some of the smallest effects pedals on the market, but all of the ones I have tried (which is most of them) sound surprisingly big. One of the latest offerings in this popular series is the E.Filter. (Figure 1) Malekko says that the pedal is based on a "popular vintage model", but never says specifically which one. Of course, I dug in and had a look to see if I could figure out which circuit it was based on. The green case and "E.Filter" name seemed to suggest the old DOD 440 Envelope Filter, and a quick comparison of the schematics and the E.Filter's circuit confirmed my hunch. Vintage pedals are a funny thing. Old and discontinued pedal models can languish in relative obscurity for years, but all it takes is for someone "famous" to use one prominently, and suddenly, the used prices will skyrocket. Such is the case with the DOD 440 Envelope Filter from the late 1970s. Jonny Greenwood of Radiohead reportedly uses one live for his solos on Lucky and Paranoid Android, and now the vintage pedals can sell for $300 a pop or more on Ebay - if you can find one. Fortunately, you can get very similar warm and funky filter sounds from the all-analog Malekko E.Filter for a much more reasonable $120.
Figure 1: The Malekko E.Filter
Overall, the pedal is well-built. The two white knobs are smooth in their sweep, although a touch on the wobbly side. Switching is true-bypass, and a small red LED illuminates to indicate active status. Even though the pedal is very small, the footswitch is placed far enough away from the knobs that I never felt they were in danger of being stepped on. The dark green paint has tons of metal flake sparkle in it, which gives it some cool visual pizzaz. (Figure 2)
Figure 2: The sparkles in the paint are even more apparent in person -- Also note the footswitch location relative to the knobs
Like the vintage pedal it is based on, the circuit uses a VTL5C2/4 vactrol. A quick look inside (Figure 3) shows how Malekko managed to cram everything into such a small case. The majority of the parts are surface mount components, and the rest of the interior is taken up by the bypass switch, the input, output and power jacks, and the two control pots. There's absolutely no room inside the tiny case for a 9V battery, and the E.Filter is exclusively DC adapter powered. The E.Filter can operate on anything from 9-12V DC, and uses a standard 2.1mm center pin negative "Boss style" power plug. For the best response, Malekko recommends using 12VDC when using the E.Filter with super high-output pickups, but with my stock Les Paul's humbuckers, Casino's P-90s and Strat's single coils, I preferred the sound and response with the pedal running at 9VDC.
Figure 3: The interior, showing the E.Filter's surface mount components and tidy layout; note that there are no trim pots or other "hidden" controls
CONTROLS AND SOUND
Unlike some of the more complicated and option-rich envelope filters on the market, the controls on the E.Filter really couldn't be much simpler. There are only two knobs - Range and Freq, which is short for Frequency. The Range knob sets the pedal's bandwidth, and the Frequency knob adjusts the effect frequency. Setting the controls is a bit more complicated than you might initially think though, and the two controls are somewhat interactive. Furthermore, since envelope filter pedals are input-level dependent, the settings that work for me with my guitars may not be optimal for you and your rig, so a little experimenting is in order to find the ideal settings. Don't let that worry you -- I was able to dial everything in, had a good handle on how the controls worked, and was happily quacking away within a few minutes of when I first started playing with the pedal.
The E.Filter is very touch responsive. In fact, your playing "touch" will have a great deal of influence on how the pedal reacts and how the filter responds. On softer notes, the effect is less dramatic, but hit it harder and it sweeps further and more audibly. You have to play somewhat evenly to consistently get the same response and filter sweep on each note, but you'll quickly get the hang of it, and of course, if you want the pedal to respond differently, all you have to do is adjust your attack and how hard you hit the strings. If you have another pedal, such as an overdrive placed before the E.Filter in your pedal chain, the E.Filter will react differently when it is engaged and when it is bypassed, especially if you have it dialed up with more than unity gain. I generally recommend putting any envelope filter early in your pedal chain -- first if at all possible -- for best results. Although it can sound good when driven by a dirt pedal, like most envelope filters and auto-wah pedals, it really will work best when nothing is between it and your guitar. Or bass. Or keyboard. Yes, in addition to working great with guitar, the E.Filter can help take even the weakest keyboard Clavinet patch to some funky Higher Ground, and it works equally well for bass too, and it brought out my inner Bootsy when I ran a Squier Jaguar Bass SS into it. It responds exceptionally well to low-frequency instruments.
This pedal is small! The case size is similar to the Hammond 1590A project box - a mere 3.7" L x 1.55" W x 1.3" H, not counting the knobs, footswitch and jacks. The small size of the pedal is great news for those of us with crowded pedalboards, and despite my initial concerns about stability, the pedal stays upright and in-place when you stomp on it, even when it's just sitting on the floor. For maximum stability, I do recommend anchoring it down to a pedalboard with some velcro or with bike chain links as brackets. Those who use chain links to mount their pedals will be pleased to learn that the Malekko case screws are long, and the sockets are threaded deeply, which makes it easy to insert the chain links in between the screw heads and the case back while still allowing you to securely tighten everything down.
Overall, the sound is very pleasant. It has a decent amount of range to it -- from subtle almost "parked wah" tones to some pretty quacky sweeps, although like the vintage model it is based on, the effect is a little more subtle and somewhat less overbearing than some other filter pedals. The sound "comes on" a little less abruptly, and the sweep is a little more sweet and flange-like in character. It's a really nice sounding pedal, and I found I could use it more often than some of the more "in your face" filter designs. The E.Filter may not be ideal for hard-core knob twiddlers who require a ton of different filter features and options, but for those who want classic Radiohead and funk tones, and who would rather spend more time playing than fiddling with controls, the E.Filter is nearly ideal; it lives up to the reputation that Malekko has earned with the rest of the Omicron line for great sounds in cool little cases at very reasonable prices. Don't be paranoid -- check one out!
Dimensions: 3.7" L x 1.8 W x 1.95" H
Power: 9-12V DC, 200 mA, 2.1mm center-negative regulated power supply (not included)
Switching: True-bypass, with red LED for status indication
Warranty: 1 year limited warranty