In this review, we will be comparing Motion XT C100 and HTM71 S2, two Passive Center Channel speakers from MartinLogan and Bowers Wilkins.
Let's have a brief look at the main features
of MartinLogan Motion XT C100 and BW HTM71 S2 first before getting into our more
detailed comparison.
| Key Specs | MartinLogan Motion XT C100 | BW HTM71 S2 |
|---|
| Brand | MartinLogan
United States · founded 1982 | Bowers Wilkins
United Kingdom · founded 1966 |
|---|
| Design | 2-way | 3-way |
|---|
| Tweeter | 1.25 x 2.4" Folded Motion XT | 1" Decoupled Carbon Dome |
|---|
| Midrange | — | 4" |
|---|
| Woofer | 2 x 6.5" Aluminum | 2 x 6.5" Aerofoil Profile |
|---|
| Frequency response | 42-25k Hz | 50-28k Hz |
|---|
| Sensitivity | 93 dB | 89 dB |
|---|
| Impedance | 5 ohms | 8 ohms |
|---|
| Power range | 20-300 watts | 30-200 watts |
|---|
| Weight | 15.40kg / 33.9lbs | 18.05kg / 39.7lbs |
|---|
| Dimensions (H x W x D) | 8" x 24" x 14-1/2"
203 x 610 x 368mm | 8-15/16" x 23-1/4" x 11-7/8"
228.0 x 591.0 x 302.0mm |
|---|
What size room are the MartinLogan Motion XT C100 and BW HTM71 S2 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 C100 |
BW HTM71 S2 |
| Near-field |
Poor |
Poor |
| Small Room |
Poor |
Average |
| Mid-size Room |
Good |
Good |
| Large Room |
Good |
Average |
| Very Large Room |
Average |
Poor |
(* 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
One of the fundamental differences between these two speakers is that Motion XT C100 is a 2-way design whereas the HTM71 S2 is a 3-way speaker. 3-way designs utilize a midrange driver in addition to the tweeter and woofer on 2-way designs. Designing a crossover for a 3-way speaker is a complicated process and generally increases the overall cost of the speaker.
MartinLogan Motion XT C100BW HTM71 S2
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 C100 |
BW HTM71 S2 |
|
Driver Setup
|
2-way
|
3-way
|
|
Tweeter
|
1.25 x 2.4-inch
|
1-inch
|
|
Midrange
|
- |
1 x 4-inch |
|
Woofer
|
2 x 6.5-inch
|
2 x 6.5-inch
|
Motion XT C100 features a 1.25 x 2.4" Folded Motion XT Tweeter and 2 x 6.5" Aluminum Woofer with a Crossover frequency at 1300Hz and 2500Hz. On the other hand, the HTM71 S2 features a 1" Decoupled Carbon Dome Tweeter, a 4" Midrange and 2 x 6.5" Aerofoil Profile Woofer.
Frequency Response
Motion XT C100 has a frequency range of 42-25k Hz whereas HTM71 S2 has a frequency range of 50-28k Hz. With a minimum frequency of 42Hz, the Motion XT C100 can go significantly deeper on the low side and provide stronger bass compared to the HTM71 S2's min frequency of 50Hz.
The graph below depicts how these two speakers compare with the max, min and average Low Frequency values of other speakers in the Center Channel class in our database.
Low Frequency
Center Channel 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 C100 is a 5 ohms speaker compared to the HTM71 S2 which has a nominal impedance of 8 ohms.
These two speakers also have different sensitivity levels. Motion XT C100 sensitivity is rated at 93 dB and the HTM71 S2's is rated at 89 dB. This 4 dB difference makes the MartinLogan Motion XT C100 a more sensitive speaker compared to BW HTM71 S2, hence will play louder with the same amount of watts.
Sensitivity
Center Channel 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 C100 can handle a max power of 300 watts RMS, whereas HTM71 S2 has a max power handling value of 200 watts RMS, 100 watts less than the Motion XT C100.
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 C100
Input Type and Bi-Amping / Bi-Wiring
Both Motion XT C100 and HTM71 S2 features dual binding post speaker terminals for bi-amping or bi-wiring.
MartinLogan Motion XT C100's Custom 5-way bi-wire tool-less binding posts terminals allows Bi-amping or bi-wiring
Cabinet Type and Port Position
Both Motion XT C100 and HTM71 S2 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.
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 C100's and BW HTM71 S2's external dimensions. MartinLogan Motion XT C100 has external dimensions of 203 x 610 x 368mm (8inch x 24inch x 14-1/2inch) whereas BW HTM71 S2 has external dimensions of 228.0 x 591.0 x 302.0mm (8-15/16 x 23-1/4 x 11-7/8inch).
BW HTM71 S2 is 19mm narrower and 66mm less deeper than MartinLogan Motion XT C100 but it is also 25mm 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 MartinLogan Motion XT C100 is approximately 2244.8cm2 / 347.9inch2 and base area of the BW HTM71 S2 is approximately 1784.8cm2 / 276.6inch2. The Motion XT C100 requires 26% more surface area than the HTM71 S2 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 C100 weighs 15.40kg / 33.9lbs and the BW HTM71 S2 weighs 18.05kg / 39.7lbs. This makes the HTM71 S2 17% heavier than the Motion XT C100.
Here is a comparison of how Motion XT C100 and HTM71 S2's weights compare with the average, max and min weights in Passive Center Channel class.
Weight
All Center Channel Speakers
MartinLogan Motion XT C100
What's in the Box of BW HTM71 S2?
Here are the items that come with the HTM71 S2:
- Center-channel loudspeaker
- Grille
- 2 Two-piece foam port plugs
- 4 Self-adhesive rubber feet
- 4 Jumper-straps (pre-installed)
- Manual
- Bowers Wilkins brochure
- Warranty Information
 Max Input Power |
300 watts
vs
200 watts
|
Handle more power from your amplifier |
 Sensitivity |
93 dB
vs
89 dB
|
Play louder with same amount of amplification power |
 Low Frequency Response |
42 Hz
vs
50 Hz
|
Generates deeper bass |
 Height |
203mm
vs
228mm
|
Easier to fit in smaller spaces |
 Driver Setup |
3-way
vs
2-way
|
Have a dedicated mid-range driver |
 Nominal Impedance |
8 ohms
vs
5 ohms
|
Less selective with amplifiers |
 High Frequency Response |
28k Hz
vs
25k Hz
|
Generates higher frequency |
 Base Surface Area |
1784cm2
vs
2244cm2
|
Takes less floor space |
 Price per pair* |
1999USD
vs
2998USD
|
costs less (*prices may change depending on the seller, location and time) |
| General |
MartinLogan Motion® XT C100 |
Bowers & Wilkins HTM71 S2 |
| Brand |
MartinLogan |
Bowers Wilkins |
| Speaker Type |
Center channel speaker |
Center channel speaker |
| Power Range |
20-300 watts |
30-200 watts |
| Sensitivity |
93 dB |
89 dB |
| Impedance |
5 ohms |
8 ohms |
| Impedance |
n/a |
3.0 ohms |
| Frequency Response |
42-25k Hz |
50-28k Hz |
Drivers |
|
|
| Woofer Quantity |
2 |
2 |
| Woofer Size |
6.5" |
6.5" |
| Woofer Composition |
Aluminum |
Aerofoil Profile |
| Woofer Surround Material |
Rubber |
Rubber |
| Tweeter Size |
1.25 x 2.4" |
1" |
| Tweeter Type |
Folded Motion XT |
Decoupled Carbon Dome |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
4" |
| Crossover Frequency |
1300Hz and 2500Hz |
n/a |
| Firing Direction |
rear |
rear |
| Suggested Break-in Period |
Allow 72 hours of break-in |
n/a |
Physical Specs |
|
|
| Height |
203.0mm (8") |
228.0mm (9") |
| Width |
610.0mm (24") |
591.0mm (23.3") |
| Depth |
368.0mm (14.5") |
302.0mm (11.9") |
| Weight |
15.40kg (33.9lbs) |
18.05kg (39.7lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Finish |
MDF/Wood veneer |
n/a |
| Available Colors |
Gloss Black, Walnut, and Satin White |
Gloss Black, Satin White, Rosenut |
| 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 C100 is the newer design, against a 2017 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 C100 digs deeper - 42Hz against 50Hz. A subwoofer would even that out. |
| Amplifier needs | A | MartinLogan Motion XT C100 is more sensitive (93dB vs 89dB), so it goes louder on the same amplifier. |
| Amplifier match | B | BW HTM71 S2 is the easier load at 8 ohms. |
| Headroom | A | MartinLogan Motion XT C100 takes more power (300W vs 200W) - more in hand in a big room. |
| Size | depends | Similar cabinet size - neither is easier to fit. |
| Expandability | depends | MartinLogan Motion XT C100: bi-amping; BW HTM71 S2: bi-amping. |
| Price | B | BW HTM71 S2 is cheaper - $1,999 against $2,998, about 33% less. |
A MartinLogan Motion XT C100 B BW HTM71 S2
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?
The usual trade-off: MartinLogan Motion XT C100 measures better, BW HTM71 S2 costs about about 50% more% less. Whether that gap is worth the money is the call only you can make - and in a normal room it is often smaller than the numbers suggest. If a subwoofer is in your plans, the bass gap largely stops mattering - you would be crossing over above 50Hz anyway, which makes the cheaper BW HTM71 S2 much easier to justify. Match it to your room: we rate MartinLogan Motion XT C100 the better fit for a large room and a very large room, and BW HTM71 S2 for a small room.
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.