In this review, we will be comparing Motion 15i and RP-400M, two Passive Bookshelf speakers from MartinLogan and Klipsch.
Let's have a brief look at the main features
of MartinLogan 15i and Klipsch RP-400M first before getting into our more
detailed comparison.
MartinLogan 15i Key Specs
- 2-way Design
- 1.0 x 1.4" Folded Motion Tweeter
- 5.25" Aluminum Woofer
- 60-25k Hz Frequency Response
- 92 dB Sensitivity
- Impedance: 5ohms
- Power Range:20-200watts
- Weight:5.40kg
- Dimensions (H x W x D): 290.0" x 6.8" x 9.4"( 290.0 x 173.0 x 240.0mm )
Klipsch RP-400M Key Specs
- 2-way Design
- 1" Tractrix Horn Tweeter
- 4" Cerametallic Woofer
- 52-25k Hz Frequency Response
- 93 dB Sensitivity
- Impedance: 8ohms
- Power Range:up to 50watts
- Weight:4.10kg
- Dimensions (H x W x D): 298.0" x 5.6" x 7.5"( 298.0 x 144.0 x 191.0mm )
What size room are the MartinLogan 15i and Klipsch RP-400M 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 15i |
Klipsch RP-400M |
| Near-field |
Poor |
Good |
| Small Room |
Average |
Good |
| Mid-size Room |
Good |
Average |
| Large Room |
Average |
Poor |
| Very Large Room |
Poor |
No way |
(* 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.)
In the following sections, we will get into more detail in order to better understand how the MartinLogan 15i and Klipsch RP-400M 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
Both Motion 15i and RP-400M are 2-way speakers.
| Driver |
MartinLogan 15i |
Klipsch RP-400M |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1.0 x 1.4-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
1 x 5.25-inch
|
1 x 4-inch
|
Motion 15i features a 1.0 x 1.4" Folded Motion Tweeter and 1 x 5.25" Aluminum Woofer with a Crossover frequency at 2700Hz. On the other hand, the RP-400M features a 1" Tractrix Horn Tweeter and 1 x 4" Cerametallic Woofer with a Crossover frequency at 1500Hz.
Frequency Response
Motion 15i has a frequency range of 60-25k Hz whereas RP-400M has a frequency range of 52-25k Hz. With a minimum frequency of 52Hz, the RP-400M can go significantly deeper on the low side and provide stronger bass compared to the Motion 15i's min frequency of 60Hz.
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 Bookshelf class in our database.
Low Frequency
Bookshelf Speakers
High Frequency
Bookshelf 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 15i is a 5 ohms speaker compared to the RP-400M which has a nominal impedance of 8 ohms.
These two speakers also have different sensitivity levels. Motion 15i sensitivity is rated at 92 dB and the RP-400M's is rated at 93 dB. This 1 dB difference makes the Klipsch RP-400M a more sensitive speaker compared to MartinLogan 15i, hence will play louder with the same amount of watts.
Sensitivity
Bookshelf 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.
Motion 15i can handle a max power of 200 watts RMS from the amp the whereas RP-400M has a max power handling value of 50 watts RMS, 150 watts less than the Motion 15i.
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
Motion 15i features Single binding posts type posts and RP-400M has a Single binding posts type posts. None of these speakers feature bi-amping/bi-wiring.
MartinLogan 15i's Custom 5-way tool-less binding posts terminals
Klipsch RP-400M's Single binding posts terminals
Cabinet Type and Port Position
Both Motion 15i and RP-400M 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.
Klipsch RP-400M Tractrix horn-shaped 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 MartinLogan 15i's and Klipsch RP-400M's external dimensions. MartinLogan 15i has external dimensions of 290.0 x 173.0 x 240.0mm ( 11.4 x 6.8 x 9.4inch) whereas Klipsch RP-400M has external dimensions of 298.0 x 144.0 x 191.0mm ( 11.7 x 5.6 x 7.5inch) .
Klipsch RP-400M is 29mm narrower and 49mm less deeper than MartinLogan 15i but it is also 8mm taller.
Below you can see the front view size comparison of MartinLogan 15i and Klipsch RP-400M in scale.
Comparison image of MartinLogan 15i and Klipsch RP-400M 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 15i is approximately 415.2cm2 / 64.4inch2 and base area of the Klipsch RP-400M is approximately 275.0cm2 / 42.6inch2. The Motion 15i requires 51% more surface area than the RP-400M which gives it a small disadvantage on placement in tight spaces.
Here is an another comparison that shows both speakers on a BDI Octave Media Cabinet, next to a standard size amplifier and turntable in scale:
Size Comparison image of MartinLogan 15i and Klipsch RP-400M on a Media Console