ME‑Geithain MO-1 MKII

Designed for outside broadcast trucks, Geithain’s compact monitors could easily find a home in music recording contexts where space is at a premium.

There’s always been a need for ultra‑compact monitors, particularly in the world of professional broadcasting. Perhaps the best‑known example is the BBC‑designed LS3/5A, born in the mid 1970s specifically for the cramped environment of outside broadcast (OB) trucks. Whenever the BBC broadcast a live event, from sports events to classical concerts, there’d be a pair of LS3/5As in the truck. But the LS3/5A was a particularly BBC phenomenon, and national broadcast companies all over the world have had, and do have, their own favourite monitors. In Germany, monitor brand ME‑Geithain, a company that can trace their roots back to the 1960s, have long been a supplier to broadcast organisations, and their MO‑1 MKII model, the subject of this review, is the archetypal ultra‑compact broadcast monitor.

While reviewing an overtly broadcast monitor might seem slightly off‑piste for the pages of Sound On Sound, the worlds of music recording, composition, production, mix and sound design can also call for compact monitoring, so there often is a role for products of this ilk. You’ve perhaps also noticed that the MO‑1 on review here is the MKII, but I was additionally supplied with a pair of MKIs to compare and contrast. I’ll cover some of the differences between the MKI and MKII later on.

The MO‑1 MKII really is pretty small, with external dimensions of 214 x 147 x 192mm (HxWxD) enclosing an internal volume of just 3.5 litres or so. Its enclosure is equipped on the side panels with tapped holes intended for the attachment of mounting hardware and, along with installation in compact studio spaces, I’d imagine ME‑Geithain have in mind compact multi‑channel (Atmos) applications.

On the front panel, behind a perforated metal grille, is a nominally 100mm‑diameter bass/mid driver with a concentrically located 19mm dome tweeter. Rather than being mounted at the apex of the bass/mid driver with the diaphragm taking on a secondary role of tweeter waveguide, as is the case with the majority of dual‑concentric driver arrays, the MO‑1 MKII tweeter is located further forward, approximately on the plane of the bass/mid driver surround. Mounting the tweeter on the bass/mid driver forward plane has the potential advantage of less modulation distortion appearing from the movement of the bass/mid diaphragm (which in a small speaker like this could be significant), but this style of concentric driver array is nevertheless relatively unusual these days, and is lower‑tech and less sophisticated than some other possible concentric driver architectures. For example, tweeters mounted at the bass/mid diaphragm apex are coincident as well as concentric: they are at the same position in space and not just on the same axis, so their time‑domain integration is potentially optimal. Furthermore, a tweeter located in front of the bass/mid driver can constitute a significant diffraction body at midrange frequencies and will potentially result in audible artefacts. But despite the potential disadvantages, the engineers at ME‑Geithain have employed this technique for many years and will undoubtedly have developed much technical expertise in optimising its behaviour and performance.

Great & Small

Somewhat surprisingly considering its diminutive dimensions, the MO‑1 MKII is a closed‑box speaker, and so eschews the potential power handling and maximum level gains of reflex loading. As I’ve described many times in these pages, closed‑box loading typically offers time‑domain benefits over reflex loading, but when it comes to very small monitors where power handling, distortion and maximum volume level are at a premium, the arguments in favour of reflex loading prevail for the vast majority of monitor manufacturers. ME‑Geithain may well have concluded that the difficulty of fitting a port of adequate diameter in such a small box swings the argument in favour of keeping the box closed.

This is a perfectly reasonable decision, but it does mean that the bass driver (and amplifier) has to work harder. While there’s nothing in ME‑Geithain’s description or the technical specification of the MO‑1 MKII to suggest that significant measures have been taken in the...