In this review, we will be comparing Motion 8i and Motion 50XTi, two Passive Center Channel speakers by MartinLogan Let's have a brief look at the main features
of MartinLogan 8i and MartinLogan 50XTi first before getting into our more
detailed comparison.
Motion 8i and Motion 50XTi are members of MartinLogan's Motion series of speakers. Below you can find the loudspeakers from this series.
MartinLogan Motion Series History
What size room are the MartinLogan 8i and MartinLogan 50XTi 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 8i and MartinLogan 50XTi compare and hopefully end up with enough arguments to decide which one of these loudspeakers is the better choice for you.
**This post contains affiliate links, and I will be compensated if you make a purchase after clicking
through my links. As an Amazon Associate I earn from qualifying purchases.
Drivers
One of the fundamental differences between these two speakers is that Motion 8i is a 2-way design whereas the Motion 50XTi 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 8i |
MartinLogan 50XTi |
|
Driver Setup
|
2-way
|
3-way
|
|
Tweeter
|
1.0 x 1.4-inch
|
1.25 x 2.4-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
2 x 4-inch
|
2 x 6.5-inch
|
Motion 8i features a 1.0 x 1.4" Folded Motion Tweeter and 2 x 4" poly cone woofers with rigid dust caps Woofer . On the other hand, the Motion 50XTi features a 1.25 x 2.4" Folded Motion XT Tweeter and 2 x 6.5" Aluminum Woofer with a Crossover frequency at 900Hz and 2200Hz.
Frequency Response
Motion 8i has a frequency range of 70-23k Hz whereas Motion 50XTi has a frequency range of 50-25k Hz. With a minimum frequency of 50Hz, the Motion 50XTi can go significantly deeper on the low side and provide stronger bass compared to the Motion 8i's min frequency of 70Hz.
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 Center Channel class in our database.
Low Frequency
Center Channel Speakers
High Frequency
Center Channel 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 8i and Motion 50XTi have the same Impedance of 4 ohms but where they differ is the sensitivity levels. Motion 8i sensitivity is rated at 89 dB and the Motion 50XTi's is at 94 dB. This 5 dB difference makes the MartinLogan 50XTi a more sensitive speaker compared to MartinLogan 8i, hence will play louder with the same amount of watts.
One thing to keep in mind that the lower impedance speakers, especially the ones that are rated at 4 ohms may put more pressure on the amplifier unit comared to higher impedance speakers especially at high volume levels, so make sure the amp you pair with the Motion 8i and the Motion 8i can provide this impedance level.
Sensitivity
Center Channel 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 8i can handle a max power of 300 watts RMS from the amp the whereas Motion 8i has a max power handling value of 180 watts RMS , 120 watts less than the Motion 50XTi.
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 50XTi features Custom 5-way bi-wire tool-less binding posts posts which make bi-amping or bi-wiring possible. Motion 8i has a Spring post which doesn't feature bi-amping/bi-wiring.
MartinLogan 8i's Spring post terminals
MartinLogan 50XTi's Custom 5-way bi-wire tool-less binding posts terminals allows Bi-amping or bi-wiring
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 8i's and MartinLogan 50XTi's external dimensions. MartinLogan 8i has external dimensions of 142.0 x 562.0 x 134.0mm ( 5-9/16 x 22-1/8 x 5-1/4inch) whereas MartinLogan 50XTi has external dimensions of 196.0 x 585.0 x 347.0mm ( 7-11/16 x 23 x 13-5/8inch) .
MartinLogan 50XTi is clearly the larger of the two speakers. Its body is 23mm wider, 54mm taller and 213mm deeper than MartinLogan 8i.
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 8i is approximately 753.1cm2 / 116.7inch2 and base area of the MartinLogan 50XTi is approximately 2030.0cm2 / 314.7inch2. The Motion 8i requires 63% less surface area than the Motion 50XTi 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 8i weighs 3.86kg / 8.5lbs and the MartinLogan 50XTi weighs 13.86kg / 30.5lbs. This makes the Motion 50XTi 259% heavier than the Motion 8i.
Here is a comparison of how Motion 8i and Motion 50XTi's weights compare with the average, max and min weights in Passive Center Channel class.
Weight
All Center Channel Speakers
What's in the Box of MartinLogan 8i?
Here are the items that are included inside the box of Motion 8i:
LCR loudspeakerGrille2 Wall-bracket2 Shoulder bolts4 Rubber bumpersCleaning clothUser-feets Manual (En/Fr)Installation templateProduct Registration Card
What's in the Box of MartinLogan 50XTi?
Here are the items that come with the Motion 50XTi:
Center-channel loudspeaker Grille 4 Rubber feet Users Manual Warranty/Registration Information
 Height |
142mm
vs
196mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
753cm2 (562x134mm)
vs
2030cm2 (585x347mm)
|
Takes less floor space |
 Price per pair* |
450USD
vs
1200USD
|
costs less (*prices may change depending on the seller, location and time) |
 Max Input Power |
300 watts
vs
180 watts
|
Handle more power from your amplifier |
 Driver Setup |
3-way
vs
2-way
|
Have a dedicated mid-range driver |
 Sensitivity |
94 dB
vs
89 dB
|
Play louder with same amount of amplification power |
 Woofer Size |
6.5 inches
vs
4 inches
|
Larger woofer |
| Low Frequency Response |
50 Hz
vs
70 Hz
|
Generates deeper bass |
 High Frequency Response |
25k Hz
vs
23k Hz
|
Generates higher frequency |
| General |
MartinLogan Motion 8i |
MartinLogan Motion 50XTi |
| Brand |
MartinLogan |
MartinLogan |
| Speaker Type |
Center channel speaker |
Center channel speaker |
| Power Range |
20-180 watts |
20-300 watts |
| Sensitivity |
89 dB |
94 dB |
| Impedance |
4 ohms |
4 ohms |
| Frequency Response |
70-23k Hz |
50-25k Hz |
Drivers |
|
|
| Woofer Quantity |
2 |
2 |
| Woofer Size |
4" |
6.5" |
| Woofer Composition |
poly cone woofers with rigid dust caps |
Aluminum |
| Woofer Surround Material |
n/a |
Rubber |
| Tweeter Size |
1.0 x 1.4" |
1.25 x 2.4" |
| Tweeter Type |
Folded Motion |
Folded Motion XT |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
n/a |
900Hz and 2200Hz |
| Firing Direction |
n/a |
rear |
| Suggested Break-in Period |
Allow 72 hours of break-in at 90 dB |
Allow 72 hours of break-in at 90 dB |
Physical Specs |
|
|
| Height |
142.0mm (5.6") |
196.0mm (7.7") |
| Width |
562.0mm (22.1") |
585.0mm (23") |
| Depth |
134.0mm (5.3") |
347.0mm (13.7") |
| Weight |
3.86kg (8.5lbs) |
13.86kg (30.5lbs) |
| Enclosure |
Passive Radiator |
Bass Reflex |
| Finish |
n/a |
MDF/Lacquer |
| Available Colors |
Gloss Black, Matt White, Red Walnut |
Walnut |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Biamp Inputs |
n/a |
Yes |
Other |
|
|
| Parts Warranty |
5 Yrs w/ Registration |
5 Years |
| Labor Warranty |
5 Yrs w/ Registration |
5 Years |