January 23, 2024

Mastro Valvola LEM: Why would I buy this pedal?

A realistic evaluation.

YouTube is full of pedal demos by pro players who get paid by (or get free products from) pedal companies. These players create best-case scenario videos for unique pedals and make them sound great, but the little boxes are often a disappointment when you plug them in at home. That’s where this series of articles comes in. I bought the Mastro Valvola LEM at full price and didn’t get paid by the company for reviewing it. (And they’re gone now.) Even when I’d love to write sonnets for this thing, I’ll do my best to hide my giddy enthusiasm and give you an honest take on LEM so you can evaluate whether or not it’s for you.

What is LEM?

Mastro Valvola’s LEM (Lysergic Emotions Module) may be a multihead, digital delay. Or it may be a musical circus on acid. Its eight programs use forward, reverse, pitch shift, bitcrush, filters, vibrato and/or glitch to create harmonious, rhythmic delays. You play something and something that sounds nothing like it comes out.

Who is LEM made for?

LEM doesn’t sound at all organic, but always sounds pleasant. Its complex, rhythmic glitchiness can feel very synth-like or computerish. Ambient and experimental players will find LEM a joy. Roots and vintage players or those looking for a conventional delay will want to stay away. (But then, personally I like the contrast LEM creates with acoustic instruments.) You want to cheat at math rock? With most programs, just crank the wet. You want unique ambience? Lay the effect back under your dry, dial the filter back and add some spatial reverb. However, I think LEM sounds best when used for its unique accompaniment. It will obviously sound at home with synths and keys.

We’re seeing advanced delay pedals like LEM as likely to appear on the console next to a DAW as they are on a pedalboard. But LEM is definitely designed as floor-friendly with its reasonable size, tilted angle, top-mounted jacks, separate Wet/Dry knobs and standard 9v power at a reasonable 100 mA.

What are LEM’s dealbreakers?

I’m guessing players looking for specific capabilities will not want to waste their time reading this whole article if there’s a dealbreaker, so let’s get those out of the way now:

  • No normal delay No matter what Mark Johnson says, LEM doesn’t do a standard delay. While it would have been nice to have a basic, single-tap delay, LEM don’t do nothin’ normal. Each of the eight modes is drastically different from each other and from the dry. LEM is by no means a replacement for your current delay, but can sit side-by-side and work separately or together.
  • Max delay: about 1 sec Since it’s a multihead delay, the rhythms are a very usuable length for standard song BPMs, but ambient players today may be looking for longer delays.
  • SPIN FV-1 chip This chip is a DSP that’s made amazing time-based sounds ubiquitous and you probably have this chip in a few modulation, delay or reverb pedals on your board right now. But the FV-1 kinda gets a bad rap: It’s often pushed in ways that don’t give you super fidelity and gets accused of sounding very recognizable. Mastro Valvola has done a solid job of pushing the limits of what the chip can do in LEM and accomplished effects that you really don’t hear in other pedals, FV-1 based or not.
  • Only basic parameter control LEM doesn’t go deep with the knobs. (But I personally like that the programs are served neat.) You can control six parameters for each program: wet, dry, feedback, delay, filter and a unique parameter for each mode. Five of those controls you’d expect on any delay. The Special knob is dedicated to adding modulation, bitcrush or reverse feedback, depending on the program. But the Delay knob can also change multiple parameters at once and completely restructure the delays.
  • No MIDI/USB While LEM is a wonderful playtoy in the studio, it’s really designed to make out there simple for live playing, so no MIDI. There is also no USB slot, so no user-updatable firmware.
  • Mono LEM is best suited for a mono board or will need to fall before stereo pedals.
  • Presets not accessible with feet only Out of the box, you need to hold the Shift button and tap the right footswitch to change presets. But plugging a footswitch into the Control jack can give hands-free access to them.

But, for most of us who enjoy pedals for what they are, none of these are dealbreakers.

What’s comparable to LEM?

Some may describe LEM as Microcosm Lite. The Hologram Microcosm uses the more advanced Blackfin processor. It has a lot more programs and a lot more parameter control than LEM, but is a big box that isn’t approachable without a steep learning curve. LEM has eight programs and four knobs so there aren’t a lot of controls to get lost in. It also has four easy-access presets represented by LED colors, which makes it a less-confusing choice for live performance. Walrus Audio Lore maybe?

All the tricks for LEM.

What follows are best practices from personal experience to get the most out of LEM.

  • Follow with a delay Though LEM is a delay, the repeats may not alway create a spatial ambience. Since LEM is not a replacement for your standard delay pedal, placing a well-timed delay (especially with stereo taps) or an delay that gets ambient afterwards can make the musically complex rhythms even more so or it can soften them up.
  • Mess up the timing LEM’s delays are complex and musical. Adding modulation or glitch afterwards can randomize the structure. Pedals like the TKOG Mini Glitch in Random mode can turn LEM regimented rhythms on their ear.
  • Follow with an ambient reverb like the ZCat Big (available in mono and stereo). Keep the reverb short to emphasize the beats or stretch long to blur them. A thick reverb like this can really change or enhance the sound of LEM.
  • Precede with compression LEM benefits with some compression before to give the reverse repeats a bit more umph. A bit of boost before may add some crunchiness, but be careful since too much can distort things in unpleasant ways.
  • Add more voices to create a harmonious wall of sound. I’ve found that real-time pitch shifting pedals are not as productive as expected with LEM. A voiced reverb like the Flux Liquid Ambience (sub-octave/octave, sub-fifth/fifth) or the Shift Line Everest in Moonshine mode after LEM can create an armada of cathedral organs.
  • Use the filter It’s the secondary effect of the Special knob and can get forgotten. But it’s useful for taming some of LEM’s more present effects to make LEM more ambient.
  • Fool with expression While you can warp LEM’s delays with tap tempo in the middle of playing. The expression jack is a superpower since it can control any parameter. If you’re not an expression-pedal person, you can try a footswitch like the Malekko Lil Buddy to add further function, like maxing feedback and warping the delay or be more subtle and open up the filter on the repeats.
  • Mess with the Delay knob. More than just lengthening the repeat pattern, it can lengthen and shorten taps at the same time or even shift to a second pattern.
  • Be mundane It’s easy to fall into the habit of cranking LEM’s wet and playing along with the repeats. But also think more conventionally to take advantage of the more normal functions LEM can do. Turn off the dry and repeats and you have one of the smoothest basic reverse effects that feed nicely into your standard delay. (You can time the reverse beats with the LED above the Tap footswitch.) Try the Low Shim fully wet as a stand-alone bass.

Will LEM stay on my board?

Your first impression may be that LEM does a bunch of quirky sounds. If you don’t really tinker with each program to understand it, you might find a setting on one-of-the-eight programs kinda cool, then get bored and think LEM doesn’t merit real estate on your pedalboard. But give this pedal its fair shake with the effect and dry at various volumes. LEM is deep, flexible and useful. Coupled with a normal delay you’ll be surprised what can be achieved.

My take.

I always liked the idea of a pedal that takes a single sound you put into it and transposes it into a menagerie. And LEM is the closest pedal I’ve found to achieve that. While it creates complex soundscapes, it’s designed not to confict with itself. In other words, you really have to work at it to get a bad sound out of it. Even when you’ve got the wet cranked, attempts to understand exactly what LEM is doing is futile, since it’s designed to be trippy. It’s addictive to strum the pattern of a few chords and let LEM provide the rhythm and harmony. Or play around it.

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