PRE-ORDER. Pre-order price $429 through December 1, 2026. From December 2, 2026, the price is $449. Pay now, get it before the holidays: shipping is estimated to begin the last week of November 2026.

The Lotus M3 is a passive reactive attenuator from Fromel Electronics, built on John Hewitt's (JohnH) design, which builds on Randall Aiken's work. It is our Lotus JohnH M2, upgraded: it starts at −3.5 dB instead of −7, moves in 1.75 dB steps instead of 3.5, runs with greatly improved cooling, and its fan takes optional external power.

HOW IT WORKS

Amp output to the Lotus Amp jack, Lotus output to your speaker. A first-stage toggle selects 3½ or 7 dB; four stage toggles add 14, 7, 3½ and 1¾ dB. That is 18 settings, 3.5 dB to 33.25 dB in 1.75 dB steps. With a 120 W amp: about 54 W at the lightest setting, 0.057 W at the deepest.

SPECS

120 W max input, passive reactive load

Impedance: 8 ohm (made in 2, 4, 8 and 16 ohms)

Attenuation 3.5–33.25 dB in 1.75 dB steps (18 settings)

Outputs: one 8 ohm cab in either of the stacked pair, or two 16 ohm cabs, one in each; center jack: one 4 ohm cab, or two 8 ohm cabs with the center jack

Bypass / Run switch (don't switch it while the amp is running)

Greatly improved cooling: 92 mm Thermalright TL-9015 fan (the M2 had 40 mm), powered by the amp's speaker signal; optional external power through the EXT Power jack, 9–18 V AC or 9–24 V DC

Shell: 3D printed glass-filled PET (PET-GF), heat deflection temperature 150 °C

Panels: matte black circuit boards with exposed copper art

Size: 167 × 115 × 90 mm on its feet, including switches and jacks

Weight: about 850 g

WHAT'S IN THE BOX

The Lotus M3 attenuator, a manual and a sticker. The manual is also online at lotus.fromelelectronics.com; the QR code on the back of the Lotus opens it.

PRE-ORDER AND WARRANTY

Pay now, get it before the holidays. Shipping is estimated to begin the last week of November 2026. 14-day refund, no questions asked. Price includes shipping in the US; $39 shipping international. 1-year warranty.

OPEN CIRCUIT

As with the M2, the circuit's schematic is open source (Creative Commons Attribution-NonCommercial); the M3's art and circuit boards are Fromel's own.

Photos are renders of the 60 W 8 ohm model.

Questions? Message us here on Reverb.