Monitor Audio Platinum 100 3G Loudspeaker Review

Posted on 9th November, 2023

Monitor Audio Platinum 100 3G Loudspeaker Review

Simon Lucas auditions a premium-priced, compact standmount speaker from an illustrious British brand…

Monitor Audio

Platinum 100 3G Standmount Loudspeaker

£4,500 RRP

Monitor Audio Platinum 100 3G Review

It is customary, is it not, that when celebrating a big birthday, you let people buy you nice things and/or show you a good time? Yet Monitor Audio has gone the other way, however. The company had its fiftieth birthday last year and decided to give everyone a treat – a thorough update to its flagship Platinum range of loudspeakers, of which the Platinum 100 3G is the smallest and most affordable member. A treat is not the same as a gift, however, and affordable is not the same as inexpensive…


No matter how much engineers appear to be running the show at Monitor Audio of late, the company's industrial designers are not taking a back seat. How else to explain the way the Platinum 100 3G standmounter is specified and presented? The third generation of the company's flagship Platinum range of passive loudspeakers comes a mere seven years after the launch of the second. This is more than enough time for everyone involved to have taken a long, hard look at how performance and aesthetics can be improved. If the Platinum 100 3G is anything to go by, every moment has been spent with noses hard to the grindstone.

Monitor Audio Platinum 100 3G Review

Aesthetically, the PL100 3G sits on the border between 'handsome' and 'purposeful'. At 398x225x326mm (HxWxD), it is one of the heftier standmounters you're likely to encounter – an impression confirmed by the speaker's 15.2kg weight. The rear-firing bass reflex port means a degree of care needs to be taken about positioning, but then the front baffle is so striking in appearance that you're unlikely to want it anywhere but centre-stage anyway.

The PL100 3G comes in a choice of piano black, piano ebony or pure satin white finishes, and my time was spent with a white pair. As you would expect from this company, the speaker is beautifully constructed. Between the anodised metal trim surrounding the drivers and the relative lack of reflectivity of the white finish, it reminded me of the white ceremonial armour worn by Joaquin Phoenix's Commodus in Gladiator. Indeed, given that the cabinet is 21mm thick at its narrowest point, it is probably pretty useful as armour too.

Monitor Audio Platinum 100 3G Review

The upper driver is a third-generation example of Monitor Audio's 'micro pleated diaphragm' high-frequency transducer, originally developed for the company's bonkers 'Concept 50' prototype loudspeakers. In layman's terms, it's a ribbon tweeter. It sits behind a complex waveguide that is designed to offer highly controlled directivity consistent in both vertical and horizontal planes. The fact that the open, textured grille looks dramatic and intriguing is probably just a happy coincidence.

Below the MPD III is a 152mm mid/bass driver. It, too, is a third-generation design, this time of Monitor Audio's 'rigid diaphragm technology'. It's a continuous profile cone constructed of three distinct layers and specified to combine strength with lightness. A Nomex honeycombed core is positioned between a thin, rigid ceramic-coated aluminium layer (this 'C-CAM' material has been a Monitor Audio thing for quite some time) and two layers of carbon fibre layered and bonded at 90-degree angles of maximum strength. Add in a big neodymium magnet, reworked motor assembly and underhung, edge-wound voice-coil for better power handling and improved pistonic control, and you have the RDT III driver assembly. Again, this is a driver with just a touch of visual theatre, as the Nomex honeycomb pattern is just about discernible on the driver's face.

Monitor Audio Platinum 100 3G Review

The crossover has received just as much attention as every other element of this design; it uses elliptical filters for optimal time-alignment and greater directivity and comes into play at slightly less than 3kHz. The reflex port has been tuned at 44Hz, and Monitor Audio is claiming an in-room frequency response of 28Hz to 60kHz. Nominal impedance is put at 4 ohms, and sensitivity is said to be 85dB. The company reckons amplification of between 75 watts and 300 watts should be appropriate, which sounds fair enough.


The notion of truth in sound is hard to pin down, isn't it? Notionally, it is high fidelity to the original source. Whatever we may call it, I reckon that we all know what's right when we hear it – just as surely as we can all recognise a musical genius doing their thing in concert. And when it comes to getting it right, this little loudspeaker is the very model of accomplishment.

Monitor Audio Platinum 100 3G Review

As soon as you hear the Platinum 100 3G, you sense this on an instinctive level. For example, the way it reproduces De La Soul's ageless 3 Feet High and Rising is a joy. It's not exactly a classic hi-fi quality recording, yet this Monitor Audio speaker proves itself well able to take on the cut'n'paste mash-up of samples, DJing and idiosyncratic rapping that defines this track – and turn it into a coherent, confident and congenial whole. Unlike a whole lot of nominal rivals, the PL100 3G doesn't look down its nose at this material. Instead, it rolls up its sleeves and gets the party started.

Low frequencies are deep, textured, and make their origin absolutely plain. Control is absolute and utterly straight-edged, so tempos and rhythms are expressed with positivity, and the recording fairly motors along. The top of the frequency range, meanwhile, attacks with crisp authority. There is no shortage of bite or aggression, but at the same time, there's never any suggestion of edginess or hardness to the treble. Instead, this speaker combines substance with shine, and the result is a top-end that's as natural and convincing as can be.

Monitor Audio Platinum 100 3G Review

In between, the midband integrates seamlessly with the bass and treble, and is little short of torrential in its powers of communication. Eloquent is a barely adequate description of the way the midrange is realised here; if there is detail in the vocal lines to be revealed, you can be confident the Monitor Audio will reveal it. The idea that you may not be getting a complete description of the character, motivation or emotional state of any of the rappers on this recording is fanciful.

Switching to the haunting ska sound of What I Like Most About You Is Your Girlfriend by The Special AKA, and the PL100 3G demonstrates the persuasive nature of its tonality. It also shows its ability to present a recording as a unified, singular event with a strong sense of performance. Between the growling brass section, a piano that seems to have been mic'd mere millimetres from its strings, a spooky-sounding vocal line and a snare drum of the biscuit-tin variety, this is a vibrant recording. The soundstage that this pair of speakers describes is well-defined, and inside it, the variations in brass stabs and keyboard vamps are given due prominence. Dynamic contrasts between verse and chorus are no less distinct.

Monitor Audio Platinum 100 3G Review

This relatively little loudspeaker doesn't seem to care less about what sort of volume level it is asked to play at. Crank it up, and the music simply gets louder, with no change of tonal balance, blurring of soundstage boundaries, or hardening of the midrange. Turn it down to tasteful dinner-party levels, and all of the frequency information remains intact from top to bottom. Some loudspeakers need to be shown the whip before you really hear what they're capable of, but that's not the case here. At modest volumes the PL100 3G still digs deep, giving you much more than just a perfunctory performance.

Monitor Audio Platinum 100 3G Review

It is possible to locate the edges of this speaker's comfort zone, of course, but you have to go a long way to find them. Wow2 by Boredoms does the trick, and, for once, the authority and control that the Monitor Audio exerts over a recording is inappropriate. The music's desire to ensure that every element of the recording is louder than everything else is intact, as is the gleefully confrontational attitude. So there is some music that the PL100 3G finds a bit beneath it, but this little loudspeaker is almost always a gregarious and enjoyable companion.


Before you can best exploit the PL100 3G, you will need to spend significant sums of money on the equipment you're using upstream of it – obviously it cannot improve a sub-par source. You'll also have to place it properly, and for this purpose the company offers its matching ST2 stands. Then, when properly positioned in a reasonably large room, the little Monitor Audio will finally give you everything that it has got. If you can accommodate its various needs, then you will find it to be among the most engaging loudspeakers around, pound-for-pound.

Visit Monitor Audio for more information


    Simon Lucas's avatar

    Simon Lucas

    Simon was editor of What Hi-Fi? magazine and website and has since written for Wired, Metro, the Guardian and Stuff, among many others. Should he find himself with a spare moment, Simon likes publishing and then quickly deleting tweets about the state of the nation (in general), the state of Aston Villa (in particular) and the state of his partner’s cat.

    Posted in:Hi-Fi Loudspeakers Bookshelf / Standmount Applause Awards 2023
    Tags: monitor audio  monitor audio group 


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