Country of Origin


The origin story of Lieutenant

Writer: Srajan Ebaen
Financial interests: click here

First M Zero Junior shown next to an M1 Classic for size reference.

From zero to hero?
Zero means… well, nothing.

Then why call a speaker range Zero?

Excellent question.

It's answered if its designer started from nothing. If he rethought the entire game. Carte blanche. Tabula rasa.

Alas, give some designers carte blanche and you might as well hand them an unlimited American Express Centurion card. They'll spend silly money to end up with a monstrosity not even a mother could love.

If you're Alain Pratali, otherwise retired savant in southern France's Marseilles, your carte blanche is stamped sanity. Now your proof-of-concept first Zero model measures just 110cm tall on a 41x55cm WxD foot print.

Top to bottom, it runs a dipole ESS AMT with a dipole Supravox paper-cone widebander. Hidden inside works a 11.8" Audio Technology woofer. Bandwidth is a sensible 35Hz to 22kHz, sensitivity a true 94dB.

But what if that zero still is too big?

How about ½ a zero? Hello Zero Junior.

It scales the concept down. The tweeter now is Alain's proprietary sub 0.12g polyester dome, the same we already met in the M3 and M1. It's based on a Western Electric 555 motor with floating 2-inch Altec diaphragm. It loads into a precision-machined ellipsoidal Delrin horn which in the above photo turned into a Laurence Dickie-style tapered tube hovering like a katana display above the enclosure.

"For Zero Junior, I was no longer forced to put the tweeter on the same vertical baffle as the mid/woofer which I had to do for the M1 and M3 to simplify their constructions. Now Junior's set-back tweeter pod corrects for the 0.3ms time offset."

The Supravox paper-cone widebander operates in dipole mode again so the box opens to it behind a grill in the back. Whereas Zero's woofer vented through three slot ports in the front, the first Junior moved those slots to the rear.

That begs questions. Is this a ported bass alignment? A TQWT? A transmission line? A hybrid?

"When I began the project, I started from scratch. I wanted to merge the very best I had ever heard as both an engineer and audiophile. A parallel goal was to make a small speaker, not a giant like we currently see them in the glossy magazines. So the Zero Junior is just 115 x 30 x 47cm and weighs 42kg."

"To get serious, let's be clear. We don't have 1001 options for bass. There's the closed box, open baffle, bass reflex, quarter wave tuning, band pass and all variants on resonant bass circuits with twin impedance peaks. I've heard them all and tried everything. It turns out that a 4th-order symmetrical band pass gives me bass that's very elegant and fast. It's my greatest listening satisfaction in the low registers. So that's what I pursued for the range of 30Hz to maximally 125Hz. The woofer chamber is sealed, a vented chamber fronts it."

Here's a video which Alain considers a good presentation on the subject though he also disagrees with the presenter. Before you flip the virtual page, be advised that this became a meandering story with numerous twists and turns; including rechristenings and joining the navy.