Mastro Valvola LEM

Mastro Valvola LEM Review



Out of the box, the first thing that I noticed about Mastro Valvola’s LEM is the shape. It is much smaller than I anticipated and While the front panel is square, it is on an incline plane like most pedalboards today. This does make it slightly easier to read while on the floor.


I must admit, after plugging in LEM, at first I was confused. I could hear the effect but not the dry signal. Soon, I discovered the SHIFT button (clearly labeled of course) that sets alternate parameters. While the WET knob controls the amount of processed signal, DRY is it’s alternate parameter. Pressing the SHIFT button and turning the WET signal clockwise will raise the guitar's original sound. The SHIFT button also sets Filter, (SPECIAL’s alternate parameter) Filter will always set the frequency of the analog filter applied to the wet signal, regardless of what mode you’re in.


1.REVERSE: With both DRY and WET signals at their max I began to experiment. Our pedal was already set on REVERSE so that’s where I began. In this setting the “SPECIAL” knob controls vibrato. I must admit that I found happiness with both at zero. With the tap set as wide as I could set it, I found the reverse tape sounds of Starla by Smashing Pumpkins. I’ve never been able to play that until I met this pedal.


2. LFO REV: Low Frequency Ramp Oscillator Reverse Delay is the second setting. (LFO REV) for short. This means every repeat can be shifted an octave higher. This is dependent upon the rate of feedback. Set at zero it rises an octave. As one turns the dial clockwise higher pitches can be heard at greater volumes. To my ear this lends itself well to legato playing and while the SPECIAL knob still controls vibrato, at this point I had found myself still choosing to leave vibrato at zero until I met setting 3.


3. LFO REV: Low Frequency Ramp Oscillator Reverse Delay is also setting three. In this mode SPECIAL is officially known as Four Pole Filter Rate. When turned clockwise this knob affects the delay signal like a wah wah pedal. With Wah more oscillation is definitely better. I turned the SPECIAL knob way up for this mode.


4. MULTI: Multi Head Tape Delay is setting four. This is what I love. Beautiful Lo-Fi aged but not broken tape recreation. Here I set the Modulation (SPECIAL) at 7/8 o’clock with the Delay maxed out and the feedback at 12 o’clock. This is a beautiful lo-fi ambient texture, similar to reverb but more distinct.


5. LOW SHIM: Low Octave Shimmer Delay. With the Filter set low, LOW SHIM reminds me of the reverb of thunder. When the filter is set high (past 12 o’clock) it sounds more like the organ at Church. In both cases I found happiness with SPECIAL (in this case bit-crusher resolution) at 10 o’clock. As the knob turns clockwise and the resolution gets lower there is scrambled electronic sound that I personally don’t enjoy.


6. LO-FI AMB: Low-fi Spatial Delay/Reverb. For bit crusher aficionados LO FI AMB is a delay and reverb in one pre-crushed for your enjoyment. Frankly, I don’t have the chops for this setting. Although I enjoyed the sound it made, I couldn’t compose music that was mutually complementary between guitar and effect. I will be revisiting this setting at a later date.


7.REV FDBK: Multi-head Delay. This mode raises the pitch of the delay by a perfect fifth. The SPECIAL knob controls the percentage of repeats that are played forwards or backwards. With all knobs at 12 o’clock, this best exemplifies the capabilities of this pedal and it’s place as an ambient sound generator.


8. SHIM: Shimmer Delay creates delay an octave higher with SPECIAL as bit crusher control. I find that the bit crusher in this mode is more useful throughout the full range than I found in setting three, LFO REV.




APPEARANCE: This was a real time review, ie. I sat with my guitar in my lap with both the pedal and my computer within arms reach and wrote my thoughts as I discovered new things. The pedal I unboxed was white and the design was beautiful. It looked Italian such as a lamborghini. There is beauty in the functionality of a design that eliminates the unnecessary and maximizes utility.


EASE OF USE: As much as I would have liked to have plugged in and just played there was a minute learning curve. That being said, at the end of the day Mastro Valvola’s LEM is set up as a standard delay pedal with Delay, Feedback, Wet/Dry and Modulation. What’s different are the modes which couldn’t be any easier to change. My favorites are REVERSE, MULTI and LOW SHIM. I now know where they are on the dial and that the SPECIAL knob handles vibrato, vibrato and crush.


USABILITY: I will have to update this one in a few weeks having literally just unboxed my own. That being said for stage use, I believe the REVERSE may come in handy. Not only Smashing Pumpkins but Chilli Peppers, Metallica etc. For home use, I am a delay always on guy and I’ve heard a lot of people are. I see myself using my LEM a lot!


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