Microphase Audio Design Tower 3 Signature review

When French audiophile, engineer and speaker designer Jean-Marie Lière approached me about a review of the Microphase Audio Design Tower 3 Signature, I was intrigued, having seen the brand at Sydney hi-fi shows but not yet having had a chance to listen at more leisure to the company’s speakers. But the overall aesthetic certainly piqued my interest. I was also excited about the chance to sit down with Jean-Marie, who explained his history and the early days of M.A.D. to me. That, and having had the opportunity to review the latest floorstanding model, means M.A.D. is now a company I’ll be keeping a close eye on in the future.

As the brand name implies, Microphase Audio Design places a strong focus on phase coherence. Indeed, Jean-Marie revealed to me that in his early days of speaker design — which he joked predated my own accumulated life years by quite a margin, back in the 1970s — he was inspired by the design principles of Elipson. He said that Elipson (founded by fellow Frenchman Joseph Léon) had “mastered phase”, and he hoped to replicate their achievement but without adopting the iconic spherical shape of Léon’s speaker designs. He ultimately wanted to produce a speaker that was even smaller than Elipson designs, and one that could be more affordable and accessible to a wider audience.

His first design was the small SAT (satellite) monitor, launched in the mid-80s, which turned out to be a critical and commercial success in France, Belgium, Germany and Scandinavia. And, true to his word, Jean-Marie managed to design the SAT to be incredibly small, just 200 x 200 x 150mm. Newer versions of the original SAT now exist today in both passive and active forms, with the MK3.3 being the most recent. This is relevant also to the floorstanders here, because the latest SAT is itself integrated into the design of the Tower 3 Signature.

While it can certainly be argued he achieved his goal, Jean-Marie admits his thinking could have been conceived as “mad”. Whether by chance or a deliberate choice, that mad way of thinking now inspires not only the name of Jean-Marie’s company (abbreviated to M.A.D.), but also his willingness to try new things when designing speakers.

EQUIPMENT

The Tower 3 Signature certainly adopts this way of thinking, as it maintains the company’s design ethos of employing a strikingly narrow baffle at just 192mm wide. While it’s not uncommon these days for speakers to be supermodel thin, the 192mm width of the Tower 3 Signature is exceptional, and requires an extended plinth of 250mm width to ensure stability while also providing “M.A.D. looks!”. Such a narrow design ensures it’s easy to accommodate in living rooms of all shapes and sizes, but it’s not just for an easy fit. The minimal width can also help to minimise baffle-step diffraction effects that can colour the midrange and smear imaging on wider fronts.

The Tower 3s aren’t especially tall, either, at 1200mm height — which includes the plinth — while their depth comes in at a manageable 440mm, again including the plinth.

As previously mentioned, the Tower 3 incorporates the SAT MK3.3, albeit in an inverted alignment, and with its 17cm bass driver being replaced with a larger 31cm alternative sourced from SB Acoustics. This sits at the base of the cabinet and fires out to the side. Clearly, Jean-Marie opted for a side-firing design owing to the slim cabinet size, but also for the sonic benefits. Side-firing woofers like this can integrate bass more smoothly into the room, as they rely on boundary reflections rather than direct radiation, reducing placement sensitivity compared to front-firing (which demands precise positioning) or rear-firing (which can boom or null in corners).

The concept of side-firing drivers isn’t new, and while he’s not necessarily credited with inventing it, they were popularised in the 1970s by Roy Allison, a former vice president of engineering and manufacturing at Acoustic Research. Allison oversaw production of many of the company’s now-legendary loudspeakers, including the AR-9. That model, known for its impressive bass output, featured opposed 12-inch side-firing woofers (one on each side) to aid vibration cancellation and room coupling. While the Tower 3 Signature uses just a single side-firing woofer, it clearly traces a history back to Allison’s boundary-friendly philosophy.

The 130mm paper-cone midrange driver continues Jean-Marie’s longstanding partnership with French speaker driver manufacturer Audax, which has been producing his custom designs since the first SAT speaker. Here it’s placed in a stepped baffle configuration to physically time-align the drivers’ acoustic centres, ensuring wavefronts from tweeter and midrange arrive simultaneously for that goal of better phase coherence and thereby a more coherent soundstage. So the Audax midrange should align perfectly with the Signature’s AMT ribbon tweeter from German company Mundorf. This AMT tweeter is a variant of Oscar Heil’s Air Motion Transformer design that has been in use since the 1970s, with a pleated diaphragm of folded ridges that increase efficiency and greatly reduce the front–back diaphragm movement compared with a typical 25mm dome tweeter.

Around the back a small reflex port is tuned to optimise the side woofer’s output, while dual speaker binding posts enable bi-amped or bi-wired modes if you wish. The crossover is a 3-way design splitting at 150Hz (12dB/octave) and 4kHz (6dB/octave), prioritising gentle slopes for natural driver integration. Microphase Audio Design lists the frequency response of the Tower 3 Signature floorstanders as 40Hz–25kHz ±2.5dB; the 40Hz lower limit should satisfy most listeners, although those looking for extra low-end oomph may want to consider adding a subwoofer. Efficiency is rated at 90dB/1W/1m, nominal impedance 4 ohms. I used the Marantz Model 50 to hand for this review — rated at 100W into 4 ohms — and as you’ll find out in the listening sessions section, it proved to be more than up to the task of driving the Tower 3 speakers.

The cabinetry deserves special mention too. The Finnish marine-grade birch plywood feels very solid and, with each speaker weighing around 25kg, they stay planted in place. This holds true whether you stand them on hard flooring or carpet, as they don’t require spikes — the plinth alone ensures they don’t move an inch. The cabinets are treated with a polyurethane coating, which not only gives them a distinctively clear and ever so slightly shiny finish, but also resists fingerprints far better than gloss. Though various components have been sourced internationally, final assembly takes place right here in Australia.

LISTENING SESSIONS

Connected to the Marantz Model 50 integrated amplifier and partnering CD 50n CD player/streamer, I first played one of my current favourite songs from American singer-songwriter Slayyyter called ‘Dance…’ — a synth-pop dancefloor number with a thumping bass-line intro.

This immediately showcased the Tower 3 Signature’s ability to deliver deep, tight, and controlled bass, with each thump of the drum pad landing with real confidence. Almost equally striking was the pinpoint stereo imaging — Slayyyter’s vocals sat dead centre, natural and clear, while the subtle echo effect on her words conveyed genuine airiness without a hint of muddiness.

For this initial test, I positioned the side-firing woofers facing outwards, each about 60cm from the nearest sidewall. Curious about the alternative, I then swapped them so the woofers faced inwards — and as soon as the same track restarted, the bass completely took over the sound. In my smaller listening room, the speakers were clearly too close together, creating too much bass buildup; however, in larger rooms, inward-facing woofers can work together for stronger central bass reinforcement. What this test also proved is that side-firing woofer designs open up more placement experimentation compared to front-firing designs.

While the speakers have a small rear port and internal padding to tame resonances, I kept experimenting with rear-wall distance. Keeping the 60cm sidewall spacing (woofers outward), I moved them from 20cm to 30cm from the rear wall and noticed a noticeably larger, more open presentation.

I also experimented with toe-in. While the Tower 3 Signature’s narrow baffle and phase-aligned drivers should theoretically disperse sound evenly for a wide sweet spot, I found angling them inwards towards my listening position by about 20° sounded better to my ears — vocals locked more precisely dead-centre, and the soundstage gained better depth and focus without narrowing excessively.

Switching to Tool’s ‘Chocolate Chip Trip’ from the Fear Inoculum album confirmed the Tower 3 Signature’s effortless handling of complex arrangements. Danny Carey’s polyrhythmic drums retained tight punch and separation, while the layered synths and atmospheric effects floated naturally in a remarkably open soundstage. The single side-firing woofer once again proved key to the overall delivery, pumping out articulate bass that supported the mix rather than dominating it.

Jessie Ware’s latest single ‘Ride’ — which offers a cheeky nod to Ennio Morricone — elevated the vocal performance even further. Ware’s sultry, emotive vocals were an undeniable highlight — rich, textured, and so viscerally real they gave me chills. Her voice was suspended perfectly in the soundstage, with the midrange and tweeter delivering on their promise of phase coherence. The overall presentation felt expansive and refined, with basslines driving the groove tautly rather than overwhelmingly. That single side-firing woofer keeps the low-end in check with sophisticated control.

Hayley Williams’ ‘Simmer’ then let them stretch their rhythmic legs — the side-firing woofers locked in with the song’s catchy groove, delivering taut kick-drum punches that had my foot tapping relentlessly. I completely forgot I was reviewing and just enjoyed the music.

CONCLUSION

As introductions to new brands go, things couldn’t have gone better with the Microphase Audio Design Tower 3 Signature. The amount of love and passion that has gone into their design and build is evident from the get go. They combine superb driver integration with fantastic build quality, forgiving placement, and genuine musical engagement. You simply must give them a listen.

LAB TEST

The overall in-room frequency response, as measured by Newport Test Labs and shown in Graph 1 for the Microphase Audio Design Tower 3 Signature loudspeakers, is extremely linear and extended such that between 60Hz and 8kHz, which is far and away the most important region of the audio band for music reproduction, the response is constrained within 2.5dB, which is to say the measured frequency response is 60Hz–8kHz ±1.25dB. Looking at the more typically reported ±3dB envelope, the frequency response is 54Hz to 20kHz ±3.0dB, which is an exceptionally fine response by anyone’s standards.

Newport Test Labs measured the high-frequency response of the Microphase Audio Design loudspeakers using a gating technique that replicates what would be measured in an anechoic chamber, and fortuitously allows far more precise frequency and level measurements to be plotted than the in-room measurement of Graph 1. It transpired that the response measured 15 degrees off-axis horizontally was slightly flatter (more linear) than the on-axis response, with a slightly lifted extreme-treble response and, since this off-axis angle will be the listening position for most listeners, we’ve elected to show this response in Graph 2. You can see there’s a very slight roll-off that commences at 4.5kHz, but it levels off at around 10kHz and extends at the same level out to around 33kHz, after which it rolls off very rapidly.

The peaks and dips in the response that are visible on this trace are so high in frequency, so little in level variation and of such high Q that they would not be audible to the human ear. If Newport Test Labs had smoothed this trace via post-processing (as most manufacturers do), these minor irregularities would have disappeared; the trace shown is raw and completely unsmoothed.

The impedance of the Microphase Audio Design Tower appears to show that the cabinet is acting as if it’s a sealed enclosure, so there’s obviously something interesting going on here that’s no doubt the explanation for the impressively extended bass response, given the cabinet volume and the bass driver’s Sd and Vmax. The impedance remains below 8 ohms between 72Hz and 550Hz, and from 4kHz to beyond 40kHz, but never drops below 4 ohms, so we’d allocate this design a nominal impedance of 4 ohms.

Newport Test Labs measured the sensitivity of the Microphase Audio Design Towers using its standard stringent measurement technique, and reported efficiency as being 87dBSPL at a distance of one metre with an input voltage of 2.83Veq., which puts it numerically at the average for most home hi-fi loudspeakers, but it will sound slightly louder in A–B comparisons due to Newport Test Labs’ methodology resulting in lower SPL levels. Overall, this is a very well-designed, electrically efficient loudspeaker system that delivers extended bass, superbly flat midrange and smoothly tailored high frequencies.