Monitor Audio Platinum 300 Speakers

Regular price $22,000.00

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Monitor Audio Platinum 300 Speakers

The Platinum 300 3G is three-way floorstander, designed to deliver a rich, dynamic high-end performance with tight, controlled bass.  

How to build a Platinum

Start with a Micro Pleated Diaphragm 3 rd gen tweeter. The moving mass of this driver is much lower than regular tweeters and therefore prvides smoother, more articulate and cleaner sound. The surface area is six times a regular tweeter, which makes it effortless and distortionless. Where most tweeters start misbehaving in the audio band this remarkable tweeter extends way out to 60 kHz without strain.


Fast, powerful response to dynamics require cones that are rigid and light. Monitor Audio engineers developed Rigid Membrane Technology to meet the challenge.

The Nomex 3 is a thin Nomex Honeycomb Membrane sealed by a 40uM (half as thick as hair) layer of Ceramic Aluminum in the front and two layers of very thin woven Carbon Fibre at the back. The result is an 8 dB lower distrotion.

An inclosure that disappears

To avoid boxy coloration, The Platinum is built with a super strong matrix enclosure. The front panel is a massive 36mm, and panels are multi layer glued wood. Energy rods brace the drivers against the rear panel for solid wave launch without exciting the front panel.

The Platinum stands on a steel frame with four spiked feet. Combined with the rigid cabinet, powerful bass impacts are controlled from an immovable foundation.

Time Coherent Crossovers

To keep all the drivers working in perfect time sync, Monitor Audio's engineers have moved on from the typical 3 rd order crossovers used in the industry to advanced ellyptical crossovers. (only Magico does this as far as we know). , 

The result? Unmatched imaging, soundstaging and presence puts you in the space with the musicians.




Stereophile adds the Platinum to their select "Editor's Choice" list.

"The speaker accomplishes what it does honestly, without smoke and mirrors. It’s a thoughtfully designed and beautifully built product that’s imperturbable with dynamic and bass-endowed source material, and a faithful communicator of musical color and character"

read the review in The Absolute Sound

HiFi plus loved the Platinum 300 - and gives it a highly commended award

"We haven’t had enough of experts!

There is, I think we can all agree, a great deal of satisfaction to be derived from being in the presence of expertise. No matter if it’s a chef or a plasterer, a guitarist or a tennis prodigy – to observe an accomplished technician in command of their skill-set is a prodigious experience. And it so proves when listening to the Monitor Audio Platinum 300 3G – no matter the music they’re given, no matter the volume level at which they’re asked to play, they’re so casually, effortlessly and unarguably in command of each and every situation that ‘enjoyment’ almost becomes ‘gratitude’. Some people would have you believe we’ve had enough of experts, but I think the opposite is true: we admire experts, and there are some situations in which an expert’s input is difficult to put a price on.

read the review in HiFi plus

video review - please allow 10 secs to load


  • System Format - 3-Way
  • Frequency Response, Free-Field (-6dB)  25 Hz 60 kHz
  • Frequency Response, In-Room (-6dB) 17 Hz – 60 kHz
  • Sensitivity (2.83 Vrms @ 1m, Free-Field)​​ 88 dB
  • Nominal Impedance   4 Ohms
  • Minimum Impedance (20 Hz to 20 kHz)​​ 4.0 Ohms @ 3.75 kHz
  • Continuous Power Handling (RMS into 4 Ohms) 400 W
  • Recommended Amplifier Power (RMS into 4 Ohm, Music Signal) 200 – 800 W
  • Bass Alignment Ported
  • Port Tuning Frequency 32 Hz
  • Crossover Frequency LF/MF: 650 Hz​, MF/HF: 3 kHz
  • Drive Unit Complement 2 x 8" RDT III bass driver, 1 x 4" RDT III mid-range driver, 
    1 x MPD III tweeter 
  • External Dimensions including Trims, Terminals & Outrigger Feet & Spikes (H x W x D)
  • 1131.1 x 429.8 x 525 mm (44.5 x 16.9 x 20.6")
  • External Dimensions including Trims, Terminals & Outrigger Feet without spikes (H x W x D)
  • 1114.5 x 429.8 x 524.4 mm (44.5 x 16.9 x 20.6")
  • Weight (each)53.6 kg (118 lb 2 oz)

Audiofi is your Monitor Audio Platinum dealer, we ship in Canada