Detroit microphone maker Deni Mesanovic applies his considerable knowledge of transducers to produce an impressive debut studio speaker.
My colleague Bob Thomas reviewed the Mesanovic Model 2 ribbon microphone back in SOS February 2016 and was extremely impressed with what he found. The second appearance for Mesanovic in this magazine is not a new microphone, however, but a high‑end, active nearfield/midfield monitor, the RTM10. So what, you might ask, is a ribbon‑mic specialist company doing manufacturing a monitor? It’s actually not quite as leftfield as it might appear because there are significant similarities between the design, engineering and manufacturing of ribbon microphones and ribbon tweeters. I’ll expand on that a little further down the page.
First, a little about the company. Based in Detroit, Mesanovic were founded by Deni Mesanovic, who had built a ribbon mic as part of his degree in Sound Engineering at the University of Michigan. That experience led him to become involved in mic manufacture on a commercial basis, initially ribbon mics and latterly a condenser model. Mesanovic are unashamedly an artisan‑style organisation, making products in low numbers and retaining as much manufacture in‑house as possible. As you might already suspect from the pictures, the RTM10 aspires to very high performance and is not an inexpensive monitor. It’s aimed at serious, professional users with a need for, and resources to invest in, high‑end studio hardware.
As nearfield monitors go the RTM10, with its single side‑mounted bass driver, is at first sight a somewhat quirky one, but there’s a good deal of thoughtful and astute electroacoustic engineering going on behind its quirks. In terms of the basic formula it’s a three‑way monitor comprising a nominally 250mm (10‑inch) bass driver, a 130mm (5‑inch) midrange driver and a 130 x 9.3 mm ribbon tweeter. The internal amplification is all Class‑D NCore from Dutch specialist Hypex. It’s rated at 250 Watts for the bass and midrange drivers and 100 Watts for the tweeter. The crossover frequencies are at 150Hz from bass driver to midrange driver, and at 3.5kHz from midrange driver to tweeter, all with steep, fourth‑order (24dB/octave) filter slopes. The band between the two crossovers (150Hz to 3.5kHz) is unusually wide and gives the midrange driver around four and a half really important octaves to cover. I’ll cover the reasons behind giving all that responsibility to the midrange driver further down the page.
The RTM cabinet is narrow, but relatively tall and decidedly deep so it makes some significant demands on mounting real‑estate. Each cabinet also of course needs a good distance of free air to the side on which the bass driver is located. Mesanovic suggest that the monitors should be installed with the bass drivers located inwards, however there is no specific acoustic argument for this arrangement. The bass drivers radiate omnidirectionally to significantly above their crossover frequency so there ought to be no significant performance difference between inwards or outwards location.
The RTM10 cabinets are constructed from 25mm MDF panels with strategically located bracing. The vertical front edges of the cabinet carry a generous radius that will reduce high‑frequency edge diffraction effects. A charcoal‑coloured textured paint finishes things off. The combination of thick MDF panels and, I suspect, a particularly heavy bass driver magnet, results in the RTM10 not falling into the ‘lightweight’ category. They’re a not insignificant 25kg each. Mind your back, and whatever you chose to stand the RTM10 on. I used a pair of heavy‑weight mass‑loaded speaker stands, but Mesanovic do make...