In this review, we will be comparing Motion 20i and BW 603, two Passive Floor-standing speakers from MartinLogan and Bowers Wilkins. Let's have a brief look at the main features
of MartinLogan 20i and B&W 603 first before getting into our more
detailed comparison.
What size room are the MartinLogan 20i and B&W 603 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 MartinLogan 20i and B&W 603 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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Drivers
One of the fundamental differences between these two speakers is that Motion 20i is a 2-way design whereas the BW 603 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.
| Driver |
MartinLogan 20i |
B&W 603 |
|
Driver Setup
|
2-way
|
3-way
|
|
Tweeter
|
1.0 x 1.4-inch
|
1-inch
|
|
Midrange
|
- |
1 x 6-inch |
|
Woofer
|
2 x 5.5-inch
|
2 x 6.5-inch
|
Motion 20i features a 1.0 x 1.4" Folded Motion Tweeter and 2 x 5.5" Aluminum Woofer with a Crossover frequency at 500Hz and 2600Hz. On the other hand, the BW 603 features a 1" Tweeter , a 6" Midrange and 2 x 6.5" Paper Woofer .
Frequency Response
Motion 20i has a frequency range of 46-25k Hz whereas BW 603 has a frequency range of 48-28k Hz. With a minimum frequency of 46Hz, the Motion 20i can go slightly deeper then the BW 603's min frequency of 48Hz.
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
None of these speakers achieves full range experience which is commonly agreed as 20Hz-20kHz. In order to achieve lower lows / deeper bass, we recommend you pair these with a subwoofer. Visit our Powered Subwoofers section to find out more about the available options.
Impedance and Sensitivity
Motion 20i is a 4 ohms speaker compared to the BW 603 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 20i can provide this impedance level.
These two speakers also have different sensitivity levels. Motion 20i sensitivity is rated at 90 dB and the BW 603's is rated at 88.5 dB. This 1 dB difference makes the MartinLogan 20i a more sensitive speaker compared to B&W 603, 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.
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 Motion 20i and BW 603 features dual binding post speaker terminals for bi-amping or bi-wiring.
MartinLogan 20i's Custom 5-way bi-wire tool-less binding posts terminals allows Bi-amping or bi-wiring
Cabinet Type and Port Position
Both Motion 20i and BW 603 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
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 MartinLogan 20i's and B&W 603's external dimensions. MartinLogan 20i has external dimensions of 905.0 x 175.0 x 307.0mm ( 35-5/8 x 6-7/8 x 12-1/16inch) whereas B&W 603 has external dimensions of 985.0 x 190.0 x 340.0mm ( 38.7 x 7.4 x 13.3inch) .
B&W 603 is clearly the larger of the two speakers. Its body is 15mm wider, 80mm taller and 33mm deeper than MartinLogan 20i.
Below you can see the front view size comparison of MartinLogan 20i and B&W 603 in scale.
Comparison image of MartinLogan 20i and B&W 603 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 20i is approximately 537.3cm2 / 83.3inch2 and base area of the B&W 603 is approximately 646.0cm2 / 100.1inch2. The Motion 20i requires 17% less surface area than the BW 603 which gives it a small advantage 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 20i weighs 15.00kg / 33lbs and the B&W 603 weighs 24.14kg / 53.1lbs. This makes the BW 603 61% heavier than the Motion 20i.
Here is a comparison of how Motion 20i and BW 603'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 MartinLogan 20i?
Here are the items that are included inside the box of Motion 20i:
Floorstanding loudspeaker2 Grilles4 Rubber feet (pre-installed)4 Spike feet (w/ nuts attached)Users ManualWarranty/Registration Information
What's in the Box of B&W 603?
Here are the items that come with the BW 603:
Floorstanding loudspeaker Grille Plinith (base) 2 Jumper-straps (pre-installed) 4 Rubber feet 4 Spike feet 4 Hex-nuts 4 Screws 4 Washers 4 Lock-washers Two-piece foam port plug Hex-key Manual Bowers & Wilkins brochure Warranty Information
 Sensitivity |
90 dB
vs
89 dB
|
Play louder with same amount of amplification power |
 Low Frequency Response |
46 Hz
vs
48 Hz
|
Generates deeper bass |
 Height |
905mm
vs
985mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
537cm2 (175x307mm)
vs
646cm2 (190x340mm)
|
Takes less floor space |
 Driver Setup |
3-way
vs
2-way
|
Have a dedicated mid-range driver |
 Nominal Impedance |
8 ohms
vs
4 ohms
|
Less selective with amplifiers |
| Woofer Size |
6.5 inches
vs
5.5 inches
|
Larger woofer |
 High Frequency Response |
28k Hz
vs
25k Hz
|
Generates higher frequency |
| General |
MartinLogan Motion 20i |
Bowers & Wilkins 603 |
| Brand |
MartinLogan |
Bowers Wilkins |
| Speaker Type |
Floor-standing speaker |
Floor-standing speaker |
| Power Range |
20-200 watts |
30-200 watts |
| Sensitivity |
90 dB |
88.5 dB |
| Impedance |
4 ohms |
8 ohms |
| Frequency Response |
46-25k Hz |
48-28k Hz |
Drivers |
|
|
| Woofer Quantity |
2 |
2 |
| Woofer Size |
5.5" |
6.5" |
| Woofer Composition |
Aluminum |
Paper |
| Woofer Surround Material |
Rubber |
Rubber |
| Tweeter Size |
1.0 x 1.4" |
1" |
| Tweeter Type |
Folded Motion |
n/a |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
6" |
| Crossover Frequency |
500Hz and 2600Hz |
n/a |
| Firing Direction |
rear |
rear |
| Suggested Break-in Period |
Allow 72 hours of break-in at 90 dB |
n/a |
Physical Specs |
|
|
| Height |
905.0mm (35.6") |
985.0mm (38.8") |
| Width |
175.0mm (6.9") |
190.0mm (7.5") |
| Depth |
307.0mm (12.1") |
340.0mm (13.4") |
| Weight |
15.00kg (33lbs) |
24.14kg (53.1lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Finish |
MDF/Lacquer |
MDF/Vinyl |
| Available Colors |
Gloss Black, Matt White, Red Walnut |
Black, White, Oak |
| 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 |