In this review, we will be comparing Platinum 300 3G and R11, two Passive Floor-standing speakers from Monitor Audio and KEF. Let's have a brief look at the main features
of Monitor Audio Platinum 300 3G and KEF R11 first before getting into our more
detailed comparison.
What size room are the Monitor Audio Platinum 300 3G and KEF R11 speakers good for?
The size of the room in which you are planning to use these loudspeakers is an important decision factor. Here we have compared their suitability to various sizes of environments considering their size and max power parameters:
In the following sections, we will get into more detail in order to better understand how the Monitor Audio Platinum 300 3G and KEF R11 compare and hopefully end up with enough arguments to decide which one of these loudspeakers is the better choice for you.
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through my links. As an Amazon Associate I earn from qualifying purchases.
Drivers
Both Platinum 300 3G and R11 are 3-way speakers.
| Driver |
Monitor Audio Platinum 300 3G |
KEF R11 |
|
Driver Setup
|
3-way
|
3-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
1 x 4-inch |
1 x 5-inch |
|
Woofer
|
2 x 8-inch
|
4 x 6.5-inch
|
Platinum 300 3G features a 1" MPD III Tweeter , a 4" Midrange and 2 x 8" RDT III Woofer with a Crossover frequency at 650 Hz - 3000 Hz. On the other hand, the R11 features a 1" aluminum Dome Tweeter , a 5" Midrange and 4 x 6.5" Hybrid Aluminum Woofer with a Crossover frequency at 400Hz and 2900Hz.
Frequency Response
Platinum 300 3G has a frequency range of 17-60k Hz whereas R11 has a frequency range of 46-28k Hz. With a minimum frequency of 17Hz, the Platinum 300 3G can go significantly deeper on the low side and provide stronger bass compared to the R11's min frequency of 46Hz.
Below graphs depict how these two speakers compare with the max, min and average values of the Min and Max Frequencies of other speakers in the Floor-standing class in our database.
Low Frequency
Floor-standing Speakers
High Frequency
Floor-standing Speakers
Monitor Audio Platinum 300 3G
Impedance and Sensitivity
Platinum 300 3G is a 4 ohms speaker compared to the R11 which has a nominal impedance of 8 ohms. Lower impedance speakers, especially the ones that are rated at 4 ohms may put more pressure on the amplifier unit especially when played at high volume levels, so make sure the amp you pair with the Platinum 300 3G can provide this impedance level.
These two speakers also have different sensitivity levels. Platinum 300 3G sensitivity is rated at 88dB and the R11's is rated at 90 dB. This 2 dB difference makes the KEF R11 a more sensitive speaker compared to Monitor Audio Platinum 300 3G, hence will play louder with the same amount of watts.
Sensitivity
Floor-standing Speakers
Power Range
Power
range is the range of input power in watts RMS that a loudspeaker is designed to handle. While using an amplifier within this range ensures the nominal performance , inputting a power that is higher than the max wattage can result in a damaged speaker.
Platinum 300 3G can handle a max power of 400 watts RMS from the amp the whereas R11 has a max power handling value of 300 watts RMS, 100 watts less than the Platinum 300 3G.
Keep in mind that a higher max power handling value doesn't necessarily make that a louder speaker
compared to a lower max handling speaker. Loudness or the sound level is also impacted by parameters
such as Impedance, sensitivity and system efficiencies.
Input Type and Bi-Amping / Bi-Wiring
Both Platinum 300 3G and R11 features dual binding post speaker terminals for bi-amping or bi-wiring.
Monitor Audio Platinum 300 3G's Binding post terminals allows Bi-amping or bi-wiring
KEF R11's Binding post terminals allows Bi-amping or bi-wiring
Cabinet Type and Port Position
Both Platinum 300 3G and R11 have rear firing ports. Rear ported speakers generally need more room between the backside of the speaker and the wall compared to sealed and front/bottom ported speakers. Placing the speakers too close to the walls may cause the bass to sound boomy.
If you are limited in space and can't get the speakers away from the backwall, check our Speakers with Front Firing Ports page.
Monitor Audio Platinum 300 3G Port
Physical Specs
Size of a speaker can sometimes become an important decision factor due to space constraints or in some cases purely for esthetic reasons. In this section, we are going to compare Monitor Audio Platinum 300 3G's and KEF R11's external dimensions. Monitor Audio Platinum 300 3G has external dimensions of 1131.1 x 429.8 x 525 mm ( 44.5 x 16.9 x 20.6-inch) whereas KEF R11 has external dimensions of 1301.0 x 312.0 x 389.0mm ( 51-3/16 x 12-1/4 x 15-5/16inch) .
KEF R11 is 118mm narrower and 136mm less deeper than Monitor Audio Platinum 300 3G but it is also 170mm taller.
Base Surface Area Comparison
Base surface area of a loudspeaker may become a determining factor when the space in your room or desk is limited.
The base surface area of the Monitor Audio Platinum 300 3G is approximately 2257.5cm2 / 349.9inch2 and base area of the KEF R11 is approximately 1213.7cm2 / 188.1inch2. The Platinum 300 3G requires 86% more surface area than the R11 which gives it a small disadvantage on placement in tight spaces.
Weight Comparison The weight of a loudspeaker can become an important factor if you need to move and reposition the unit often. Weight of a speaker can also "sometimes" be an indicator of the rigidity of the enclosure and the quality of the internal components used. The Monitor Audio Platinum 300 3G weighs 53.60kg / 117.9lbs and the KEF R11 weighs 37.70kg / 82.9lbs. This makes the Platinum 300 3G 42% heavier than the R11.
Here is a comparison of how Platinum 300 3G and R11's weights compare with the average, max and min weights in Passive Floor-standing class.
Weight
All Floor-standing Speakers
Monitor Audio Platinum 300 3G
What's in the Box of KEF R11?
Here are the items that come with the R11:
Floorstanding loudspeakerGrille2 Foam port plugs4 Outrigger feet4 Spikes4 Protective discs4 Screws4 WashersWrenchHex-keyUser ManualWarranty Information
 Max Input Power |
400 watts
vs
300 watts
|
Handle more power from your amplifier |
 Minimum Impedance |
4 ohms
vs
3.2 ohms
|
Very low impedance levels puts more pressure on amplifier |
 Woofer Size |
8 inches
vs
6.5 inches
|
Larger woofer |
| Low Frequency Response |
17 Hz
vs
46 Hz
|
Generates deeper bass |
 High Frequency Response |
60k Hz
vs
28k Hz
|
Generates higher frequency |
 Height |
1131mm
vs
1301mm
|
Easier to fit in smaller spaces |
 Sensitivity |
90 dB
vs
88 dB
|
Play louder with same amount of amplification power |
 Nominal Impedance |
8 ohms
vs
4 ohms
|
Less selective with amplifiers |
| Number of Woofers |
4
vs
2
|
More woofers |
 Base Surface Area |
1213cm2 (312x389mm)
vs
2257cm2 (430x525mm)
|
Takes less floor space |
 Price per pair* |
6000USD
vs
17900USD
|
costs less (*prices may change depending on the seller, location and time) |
| General |
Monitor Audio Platinum 300 3G |
KEF R11 |
| Brand |
Monitor Audio |
KEF |
| Speaker Type |
Floor-standing speaker |
Floor-standing speaker |
| Power Range |
up to 400 watts |
15-300 watts |
| Sensitivity |
88dB |
90 dB |
| Impedance |
4 ohms |
8 ohms |
| Impedance |
4 ohms |
3.2 ohms |
| Frequency Response |
17-60k Hz |
46-28k Hz |
Drivers |
|
|
| Woofer Quantity |
2 |
4 |
| Woofer Size |
8" |
6.5" |
| Woofer Composition |
RDT III |
Hybrid Aluminum |
| Woofer Surround Material |
n/a |
Rubber |
| Tweeter Size |
1" |
1" |
| Tweeter Type |
n/a |
Dome |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
4" |
5" |
| Crossover Frequency |
650 Hz - 3000 Hz |
400Hz and 2900Hz |
| Firing Direction |
rear |
rear |
Physical Specs |
|
|
| Height |
1131.0mm (44.5") |
1301.0mm (51.2") |
| Width |
430.0mm (16.9") |
312.0mm (12.3") |
| Depth |
525.0mm (20.7") |
389.0mm (15.3") |
| Weight |
53.60kg (117.9lbs) |
37.70kg (82.9lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Finish |
n/a |
MDF/Lacquer |
| Available Colors |
Piano Black, Piano Ebony, Satin White |
Black Gloss, White Gloss, Walnut |
| Grille |
n/a |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Biamp Inputs |
Yes |
Yes |
Other |
|
|
| Parts Warranty |
|
5 Years |
| Labor Warranty |
|
5 Years |