In this review, we will be comparing Motion F20 and 704 S2, two Passive Floor-standing speakers from MartinLogan and Bowers Wilkins.
Let's have a brief look at the main features
of MartinLogan Motion F20 and B&W 704 S2 first before getting into our more
detailed comparison.
| Key Specs | MartinLogan Motion F20 | B&W 704 S2 |
|---|
| Design | 3-way | 3-way |
|---|
| Tweeter | 1.0 x 1.4" Folded Motion Ribbon | 1" |
|---|
| Midrange | 5.5" | 5" |
|---|
| Woofer | 2 x 5.5" Aluminum | 2 x 5" Aerofoil |
|---|
| Frequency response | 35-25k Hz | 48-28k Hz |
|---|
| Sensitivity | 92 dB | 88 dB |
|---|
| Impedance | 4 ohms | 8 ohms |
|---|
| Power range | 20-300 watts | 30-150 watts |
|---|
| Weight | 27.20kg / 59.8lbs | 18.50kg / 40.7lbs |
|---|
| Dimensions (H x W x D) | 44-3/4" x 11-3/4" x 14-1/4"
1127 x 298 x 362mm | 37.8" x 6.5" x 10.9"
959.0 x 165.0 x 277.0mm |
|---|
What size room are the MartinLogan Motion F20 and B&W 704 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 F20 |
B&W 704 S2 |
| Near-field |
Bad |
Bad |
| Small Room |
Poor |
Poor |
| Mid-size Room |
Average |
Good |
| Large Room |
Good |
Good |
| 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.
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through our links. As an Amazon Associate I earn from qualifying purchases.
Drivers
Both Motion F20 and 704 S2 are 3-way speakers.
MartinLogan Motion F20B&W 704 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 F20 |
B&W 704 S2 |
|
Driver Setup
|
3-way
|
3-way
|
|
Tweeter
|
1.0 x 1.4-inch
|
1-inch
|
|
Midrange
|
1 x 5.5-inch |
1 x 5-inch |
|
Woofer
|
2 x 5.5-inch
|
2 x 5-inch
|
Motion F20 features a 1.0 x 1.4" Folded Motion Ribbon Tweeter, a 5.5" Midrange and 2 x 5.5" Aluminum Woofer with a Crossover frequency at 230Hz and 2600Hz. On the other hand, the 704 S2 features a 1" Tweeter, a 5" Midrange and 2 x 5" Aerofoil Woofer.
Frequency Response
Motion F20 has a frequency range of 35-25k Hz whereas 704 S2 has a frequency range of 48-28k Hz. With a minimum frequency of 35Hz, the Motion F20 can go significantly deeper on the low side and provide stronger bass compared to the 704 S2'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 F20 is a 4 ohms speaker compared to the 704 S2 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 F20 can provide this impedance level.
These two speakers also have different sensitivity levels. Motion F20 sensitivity is rated at 92 dB and the 704 S2's is rated at 88 dB. This 4 dB difference makes the MartinLogan Motion F20 a more sensitive speaker compared to B&W 704 S2, 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 F20 can handle a max power of 300 watts RMS, whereas 704 S2 has a max power handling value of 150 watts RMS, 150 watts less than the Motion F20.
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.
Input Type and Bi-Amping / Bi-Wiring
Both Motion F20 and 704 S2 features dual binding post speaker terminals for bi-amping or bi-wiring.
MartinLogan Motion F20's Custom 5-way bi-wire tool-less binding posts terminals allows Bi-amping or bi-wiring
Cabinet Type and Port Position
Motion F20 has a bottom firing port whereas 704 S2 has a rear firing ports. MartinLogan Motion F20's bottom-firing port gives more flexibility in placement in regards to proximity to walls compared to B&W 704 S2 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 F20's and B&W 704 S2's external dimensions. MartinLogan Motion F20 has external dimensions of 1127 x 298 x 362mm (44-3/4inch x 11-3/4inch x 14-1/4inch) whereas B&W 704 S2 has external dimensions of 959.0 x 165.0 x 277.0mm (37.8-inch x 6.5-inch x 10.9-inch).
MartinLogan Motion F20 is clearly the larger of the two speakers. Its body is 133mm wider, 168mm taller and 85mm deeper than B&W 704 S2.
Below you can see the front view size comparison of MartinLogan Motion F20 and B&W 704 S2 in scale.
Comparison image of MartinLogan Motion F20 and B&W 704 S2 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 F20 is approximately 1078.8cm2 / 167.2inch2 and base area of the B&W 704 S2 is approximately 457.1cm2 / 70.9inch2. The Motion F20 requires 136% more surface area than the 704 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 F20 weighs 27.20kg / 59.8lbs and the B&W 704 S2 weighs 18.50kg / 40.7lbs. This makes the Motion F20 47% heavier than the 704 S2.
Here is a comparison of how Motion F20 and 704 S2's weights compare with the average, max and min weights in Passive Floor-standing class.
Weight
All Floor-standing Speakers
What's in the Box of B&W 704 S2?
Here are the items that come with the 704 S2:
- Floorstanding loudspeaker
- Grille
- Plinth (base)
- 2 Jumper-straps (pre-installed)
- Two-piece foam port plug
- 4 Rubber feet
- 4 Spike feet
- 4 Lock-nuts
- 4 Screws
- 4 Washers
- 4 Lock washers
- Hex-key
- Manual
- Bowers & Wilkins brochure
- Warranty Information
 Max Input Power |
300 watts
vs
150 watts
|
Handle more power from your amplifier |
 Sensitivity |
92 dB
vs
88 dB
|
Play louder with same amount of amplification power |
 Woofer Size |
5.5 inches
vs
5 inches
|
Larger woofer |
|
Low Frequency Response |
35 Hz
vs
48 Hz
|
Generates deeper bass |
 Price per pair* |
3498USD
vs
3500USD
|
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 |
959mm
vs
1127mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
457cm2
vs
1078cm2
|
Takes less floor space |
| General |
MartinLogan Motion F20 |
Bowers & Wilkins 704 S2 |
| Brand |
MartinLogan |
Bowers Wilkins |
| Speaker Type |
Floor-standing speaker |
Floor-standing speaker |
| Power Range |
20-300 watts |
30-150 watts |
| Sensitivity |
92 dB |
88 dB |
| Impedance |
4 ohms |
8 ohms |
| Impedance |
n/a |
3.1 ohms |
| Frequency Response |
35-25k Hz |
48-28k Hz |
Drivers |
|
|
| Woofer Quantity |
2 |
2 |
| Woofer Size |
5.5" |
5" |
| Woofer Composition |
Aluminum |
Aerofoil |
| Woofer Surround Material |
Rubber |
Rubber |
| Tweeter Size |
1.0 x 1.4" |
1" |
| Tweeter Type |
Folded Motion Ribbon |
n/a |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
5.5" |
5" |
| Crossover Frequency |
230Hz and 2600Hz |
n/a |
| Firing Direction |
bottom |
rear |
| Suggested Break-in Period |
Allow 72 hours of break-in |
n/a |
Physical Specs |
|
|
| Height |
1127.0mm (44.4") |
959.0mm (37.8") |
| Width |
298.0mm (11.7") |
165.0mm (6.5") |
| Depth |
362.0mm (14.3") |
277.0mm (10.9") |
| Weight |
27.20kg (59.8lbs) |
18.50kg (40.7lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Finish |
n/a |
MDF/Lacquer |
| Available Colors |
Gloss Black, Walnut, and Satin White |
Rosewood, Gloss Black, Satin White |
| 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 F20 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 F20 digs deeper - 35Hz against 48Hz. |
| Amplifier needs |
A |
MartinLogan Motion F20 is more sensitive (92dB vs 88dB), so it goes louder on the same amplifier. |
| Amplifier match |
B |
B&W 704 S2 is the easier load at 8 ohms; the other is 4 ohms and wants an amplifier rated for it. |
| Headroom |
A |
MartinLogan Motion F20 takes more power (300W vs 150W) - more in hand in a big room. |
| Size |
depends |
B&W 704 S2 is easier to place; MartinLogan Motion F20 is bigger, which usually goes with fuller bass. Your room decides. |
| Expandability |
depends |
MartinLogan Motion F20: bi-amping; B&W 704 S2: bi-amping. B&W 704 S2 sits in a wider range (8 models), so a matched surround system is easier later. |
| Price |
evenly matched |
Much the same money ($3,498 vs $3,500 a pair). |
A MartinLogan Motion F20
B B&W 704 S2
depends neither is better in the abstract - it turns on your room, placement 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 F20 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 F20 the better fit for a very large room, and B&W 704 S2 for a mid-size 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.