In this review, we will be comparing Motion XT F100 and R7, two Passive Floor-standing speakers from MartinLogan and KEF.
Let's have a brief look at the main features
of MartinLogan Motion XT F100 and KEF R7 first before getting into our more
detailed comparison.
| Key Specs | MartinLogan Motion XT F100 | KEF R7 |
|---|
| Brand | MartinLogan
United States · founded 1982 | KEF
United Kingdom · founded 1961 |
|---|
| Design | 3-way | 3-way |
|---|
| Uni-Q driver | — | 12th Generation Uni-Q |
|---|
| Tweeter | 1.25 x 2.4" Folded Motion XT | 1" Dome |
|---|
| Midrange | 6.5" | 5" |
|---|
| Woofer | 3 x 6.5" Aluminum | 2 x 6.5" Hybrid Aluminum |
|---|
| Frequency response | 31-25k Hz | 48-28k Hz |
|---|
| Sensitivity | 92 dB | 88 dB |
|---|
| Impedance | 4 ohms | 8 ohms |
|---|
| Power range | 20-450 watts | 15-250 watts |
|---|
| Weight | 34.50kg / 75.9lbs | 31.40kg / 69.1lbs |
|---|
| Dimensions (H x W x D) | 47-3/4" x 12-1/2" x 15"
1213 x 318 x 381mm | 43-13/16" x 8" x 15-5/16"
1113.0 x 200.0 x 389.0mm |
|---|
What size room are the MartinLogan Motion XT F100 and KEF R7 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:
| Listening Environment* |
MartinLogan Motion XT F100 |
KEF R7 |
| Near-field |
Are you nuts? |
Bad |
| Small Room |
Poor |
Poor |
| Mid-size Room |
Average |
Average |
| Large Room |
Good |
Good |
| Very Large Room |
Good |
Average |
(* Approximate Room sizes: Small < 100sq. ft / 9 m2,
Mid-size: 100-220 sq. ft / 9-20 m2, Large 220-400 sq. ft / 20-36 m2, Very Large: >
400 sq. ft / 36 m2.
Average Floor Height: 9" / 2.7m. Typical room sizes differ from country to country, and the actual
listening experience changes depending on floor height, room shape, surface materials, listening
position, speaker locations, etc.)
The sections below take each area in turn: drivers, frequency response, physical size and what you get in the box.
Drivers
Both Motion XT F100 and R7 are 3-way speakers.
MartinLogan Motion XT F100KEF R7
TweeterMidrangeWoofer
Front view, drawn to scale - cabinets and drivers share one scale, so sizes are directly comparable. Hover a driver for its size.
| Driver |
MartinLogan Motion XT F100 |
KEF R7 |
|
Driver Setup
|
3-way
|
3-way
|
|
Tweeter
|
1.25 x 2.4-inch
|
1-inch
|
|
Midrange
|
1 x 6.5-inch |
1 x 5-inch |
|
Woofer
|
3 x 6.5-inch
|
2 x 6.5-inch
|
Motion XT F100 features a 1.25 x 2.4" Folded Motion XT Tweeter, a 6.5" Midrange and 3 x 6.5" Aluminum Woofer with a Crossover frequency at 280Hz and 2600Hz. On the other hand, the R7 features a 1" aluminum Dome Tweeter, a 5" Midrange and 2 x 6.5" Hybrid Aluminum Woofer with a Crossover frequency at 400Hz and 2900Hz.
Frequency Response
Motion XT F100 has a frequency range of 31-25k Hz whereas R7 has a frequency range of 48-28k Hz. With a minimum frequency of 31Hz, the Motion XT F100 can go significantly deeper on the low side and provide stronger bass compared to the R7's min frequency of 48Hz.
The graph below depicts how these two speakers compare with the max, min and average Low Frequency values of other speakers in the Floor-standing class in our database.
Low Frequency
Floor-standing Speakers
Neither pair reaches down to 20Hz, the usual definition of full-range, which is normal for speakers of this size. If you want the bottom octave for movies or bass-heavy music, add a subwoofer to whichever you choose. Visit our Powered Subwoofers section to find out more about the available options.
Impedance and Sensitivity
Motion XT F100 is a 4 ohms speaker compared to the R7 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 Motion XT F100 can provide this impedance level.
These two speakers also have different sensitivity levels. Motion XT F100 sensitivity is rated at 92 dB and the R7's is rated at 88 dB. This 4 dB difference makes the MartinLogan Motion XT F100 a more sensitive speaker compared to KEF R7, 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. Staying
within that range gives nominal performance; driving the speaker beyond its maximum wattage can damage it.
Motion XT F100 can handle a max power of 450 watts RMS, whereas R7 has a max power handling value of 250 watts RMS, 200 watts less than the Motion XT F100.
Note that higher power handling does not make a speaker louder: that depends mainly on
sensitivity and impedance. The calculator below shows how loud each of these actually plays
on a real amplifier.
Which plays louder on your amplifier?
Starting with a popular amplifier - change it to the one you own, or any you are
considering, and watch both numbers move.
MartinLogan Motion XT F100
Input Type and Bi-Amping / Bi-Wiring
Both Motion XT F100 and R7 features dual binding post speaker terminals for bi-amping or bi-wiring.
MartinLogan Motion XT F100's Custom 5-way bi-wire tool-less binding posts terminals allows Bi-amping or bi-wiring
KEF R7's Binding post terminals allows Bi-amping or bi-wiring
Cabinet Type and Port Position
Motion XT F100 has a bottom firing port whereas R7 has a rear firing ports. MartinLogan Motion XT F100's bottom-firing port gives more flexibility in placement in regards to proximity to walls compared to KEF R7 with its rear-firing port.
Physical Specs
The size of a speaker can sometimes be an important decision factor due to space constraints or in some cases purely for esthetic reasons. In this section, we are going to compare MartinLogan Motion XT F100's and KEF R7's external dimensions. MartinLogan Motion XT F100 has external dimensions of 1213 x 318 x 381mm (47-3/4inch x 12-1/2inch x 15inch) whereas KEF R7 has external dimensions of 1113.0 x 200.0 x 389.0mm (43-13/16 x 8 x 15-5/16inch).
KEF R7 is 118mm narrower and 100mm shorter than MartinLogan Motion XT F100 but it is also 8mm deeper.
Below you can see the front view size comparison of MartinLogan Motion XT F100 and KEF R7 in scale.
Comparison image of MartinLogan Motion XT F100 and KEF R7 Size and External Dimensions
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 MartinLogan Motion XT F100 is approximately 1211.6cm2 / 187.8inch2 and base area of the KEF R7 is approximately 778.0cm2 / 120.6inch2. The Motion XT F100 requires 56% more surface area than the R7 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 MartinLogan Motion XT F100 weighs 34.50kg / 75.9lbs and the KEF R7 weighs 31.40kg / 69.1lbs. This makes the Motion XT F100 10% heavier than the R7.
Here is a comparison of how Motion XT F100 and R7's weights compare with the average, max and min weights in Passive Floor-standing class.
Weight
All Floor-standing Speakers
MartinLogan Motion XT F100
What's in the Box of KEF R7?
Here are the items that come with the R7:
- Floorstanding loudspeaker
- Grille
- 2 Foam port plugs
- 4 Outrigger feet
- 4 Spikes
- 4 Protective discs
- 4 Screws
- 4 Washers
- Wrench
- Hex-key
- User Manual
- Warranty Information
 Max Input Power |
450 watts
vs
250 watts
|
Handle more power from your amplifier |
 Sensitivity |
92 dB
vs
88 dB
|
Play louder with same amount of amplification power |
 Number of Woofers |
3
vs
2
|
More woofers |
|
Low Frequency Response |
31 Hz
vs
48 Hz
|
Generates deeper bass |
 Price per pair* |
4498USD
vs
4500USD
|
costs less (*prices may change depending on the seller, location and time) |
 Nominal Impedance |
8 ohms
vs
4 ohms
|
Less selective with amplifiers |
 High Frequency Response |
28k Hz
vs
25k Hz
|
Generates higher frequency |
 Height |
1113mm
vs
1213mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
778cm2
vs
1211cm2
|
Takes less floor space |
| General |
MartinLogan Motion® XT F100 |
KEF R7 |
| Brand |
MartinLogan |
KEF |
| Speaker Type |
Floor-standing speaker |
Floor-standing speaker |
| Power Range |
20-450 watts |
15-250 watts |
| Sensitivity |
92 dB |
88 dB |
| Impedance |
4 ohms |
8 ohms |
| Impedance |
n/a |
3.2 ohms |
| Frequency Response |
31-25k Hz |
48-28k Hz |
Drivers |
|
|
| Woofer Quantity |
3 |
2 |
| Woofer Size |
6.5" |
6.5" |
| Woofer Composition |
Aluminum |
Hybrid Aluminum |
| Woofer Surround Material |
Rubber |
Rubber |
| Tweeter Size |
1.25 x 2.4" |
1" |
| Tweeter Type |
Folded Motion XT |
Dome |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
6.5" |
5" |
| Crossover Frequency |
280Hz and 2600Hz |
400Hz and 2900Hz |
| Firing Direction |
bottom |
rear |
| Suggested Break-in Period |
Allow 72 hours of break-in |
n/a |
Physical Specs |
|
|
| Height |
1213.0mm (47.8") |
1113.0mm (43.8") |
| Width |
318.0mm (12.5") |
200.0mm (7.9") |
| Depth |
381.0mm (15") |
389.0mm (15.3") |
| Weight |
34.50kg (75.9lbs) |
31.40kg (69.1lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Finish |
MDF/Wood veneer |
MDF/Lacquer |
| Available Colors |
Gloss Black, Walnut, and Satin White |
Black Gloss, White Gloss, Walnut |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Biamp Inputs |
Yes |
Yes |
Other |
|
|
| Parts Warranty |
5 Years |
5 Years |
| Labor Warranty |
5 Years |
5 Years |
A generation apart: MartinLogan Motion XT F100 is the newer design, against a 2018 model. Newer is not automatically better, but the older one is more likely to be discounted or near run-out.
| Area | Better | Why |
|---|
| Bass | A | MartinLogan Motion XT F100 digs deeper - 31Hz against 48Hz. |
| Amplifier needs | A | MartinLogan Motion XT F100 is more sensitive (92dB vs 88dB), so it goes louder on the same amplifier. |
| Amplifier match | B | KEF R7 is the easier load at 8 ohms; the other is 4 ohms and wants an amplifier rated for it. |
| Headroom | A | MartinLogan Motion XT F100 takes more power (450W vs 250W) - more in hand in a big room. |
| Size | depends | KEF R7 is easier to place; MartinLogan Motion XT F100 is bigger, which usually goes with fuller bass. Your room decides. |
| Expandability | depends | MartinLogan Motion XT F100: bi-amping; KEF R7: bi-amping. |
| Price | evenly matched | Much the same money ($4,498 vs $4,500 a pair). |
A MartinLogan Motion XT F100 B KEF R7
depends neither is better in the abstract - it turns on your room, your system or how you will use them. Only specs published for both speakers are judged; anything missing on either side is left out rather than guessed.
Which should you choose?
MartinLogan Motion XT F100 has the edge on paper, though the margin is not large. The rows marked "depends" may matter more to you than the score does. If a subwoofer is in your plans, the bass gap largely stops mattering - you would be crossing over above 48Hz anyway, so judge these on the other rows instead. Match it to your room: we rate MartinLogan Motion XT F100 the better fit for a very large room; elsewhere the two are rated the same.
And remember what a spec sheet cannot show: how each looks in your room and whether the finish suits it, what dealer support and warranty are like where you live, and how they actually sound to you. If you can hear them first - ideally with your own music - that will tell you more than any number above.