The Monitor Audio PL100 Loudspeaker

Small, but perfectly formed...

For relatively old lags like myself the Monitor Audio name will forever be associated with its charismatic founder Mo Iqbal, a larger than life character whose favourite catchphrase was ‘gold domes matey’, a reference to the gold anodised finish that distinguished the firm’s top-line models in his day. One look at the new Platinum Line that now occupies the high ground in MA’s portfolio will reveal that that phrase is no longer appropriate; there are no domes in evidence, gold or otherwise. Instead the three models in the Platinum range carry a ribbon tweeter in their luxuriously finished cabinets, marking a distinct change of direction for the company.

The Platinum series consists of the £2,300 PL100 stand-mount under consideration, the £5,000 PL300 floorstander which adds a pair of eight inch bass drivers to the PL100’s bass/mid and treble units and the £2,300 PL350C three-way, four-driver centre channel. Custom designed stands are also made for the two smaller models and a pair was bolted onto the PL100s for this review; at £350 a pair they’re not cheap but they are very nicely conceived and executed. A large, sculpted ARC plinth (anti-resonance composite, which is a polymer based material that is apparently similar to Bakolite) sits on large but shallow bullet shaped spikes that can be adjusted from above. Alternatively they can be removed leaving chunky rubber O-rings to interface with a hard floor surface. The main column is in powder coated aluminium and has a cable routing slot in the rear that will take reasonably thick cables but probably not the sort of thing you’d expect to use with a speaker of this price. The column is bitumen damped to kill any ringing. On top there are two steel top plates separated by chrome spacers with bolts running through them into the cabinet itself, with damping washers between cabinet and metalwork to further prevent ringing in the stand. Without spikes this stand raises the speaker 630mm off the ground, the spikes add another 25mm but will usually sink into the carpet.

The cabinet has a deep and luxurious finish on its veneered parts, equal to any other speaker this size, regardless of price, an impression underpinned by the beautifully machined and platinum plated WBT terminals on the rear and the leather upholstery on the front baffle. The veneer on this pair is Santos rosewood, but ebony is also an option. Each is coated with 11 layers of polyester lacquer to produce that deep sheen for hours of buffing pleasure. The front baffle is covered in Strathspey leather that is so uniform that the uninitiated might mistake it for the increasingly convincing leatherettes available nowadays. Look closely however and you can see variations in the grain, sniff closely and you can tell it once adorned a cow, albeit in a slightly more furry state.

The actual cabinet is made from 15 being 25mm thin wooden laminates that end up thick, shaped to produce the curved sides and back panel and then internally braced. The whole cabinet is tensioned with a large bolt whose head sits between the reflex port and the terminals, the idea being that any remaining resonances can be tuned out. The front baffle is also made out of ARC, which looks like cast aluminium but doesn’t have the same tendency to ring – which is quite useful.

What differentiates the Platinums from the rest of the MA range and quite a few other speakers is that ribbon tweeter. This was developed by Dean Hartley and MA’s design team, and while it’s based on existing technology it does differ in subtle but important ways. I asked Dean why he chose to go down this relatively difficult route, rather than picking a proven unit from an OEM supplier. By making it in-house MA can ensure consistency of production and longterm stability, as well as being able to engineer the response to fit in with the 165mm mid-bass drive unit, a pairing that means that the ribbon has to extend down to 2.5kHz, something which he found few OEM units were capable of doing. He decided to make the change to a ribbon because of a desire to achieve very high frequency extension, something that ribbons are inherently better at, the purpose being to provide a wide-band speaker that could make the most of highresolution formats.

The mid-bass driver has to be pretty nimble to match the characteristics of the ribbon so MA developed a new cone. This is made of a sandwich of ceramic coated aluminium/ magnesium (C-CAM) either side of a Nomex honeycomb centre which provides rigidity. MA has managed to produce a very lightweight drive unit that uses the same C-CAM material as the ribbon tweeter in its construction and is said to be significantly more rigid than a traditional metal cone. Each drive-unit is housed in a diecast alloy chassis. The bass mid basket curved to match the baffle. Its motor system was developed using FEA software to minimise distortion and maximise linearity and its reflex port fashioned to allow rapid, turbulence free movement of air; standard stuff but still reassuring. Most of the listening was conducted with a Resolution Audio Opus 21 disc spinner, a Classé CP-700 pre-amp and CA-2200 power amp, an amplifier combination whose smooth resolution and reserves of power were ideal for this open and revealing loudspeaker. While being an exceptional all-round design, where it scores over often larger and more expensive speakers is at higher frequencies, where that ribbon gives it an unfair advantage. This unit combined with the small and inert nature of the cabinetmakes for superb imaging, producing instruments and voices that are in the room and totally disconnected from the loudspeakers themselves, which is a nice trick if it can be done in an even-handed fashion. And the PL100 can; it has enough bass extension and power to create palpability and weight which underpins the mid and treble and gives great recordings the gravitas they deserve. It is not going to compete in the bass with larger speakers but you are not left wanting. Everything from a piano to a kick drum has the body that it warrants.