In this review, we will be comparing Motion 30i and Motion 8i, two Passive Center Channel speakers by MartinLogan Let's have a brief look at the main features
of MartinLogan 30i and MartinLogan 8i first before getting into our more
detailed comparison.
Motion 30i and Motion 8i 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 30i and MartinLogan 8i 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 30i and MartinLogan 8i 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 30i and Motion 8i are 2-way speakers.
| Driver |
MartinLogan 30i |
MartinLogan 8i |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1.0 x 1.4-inch
|
1.0 x 1.4-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
1 x 5.25-inch
|
2 x 4-inch
|
Motion 30i features a 1.0 x 1.4" Folded Motion Tweeter and 1 x 5.25" Aluminum Woofer with a Crossover frequency at 400Hz and 2600Hz. On the other hand, the Motion 8i features a 1.0 x 1.4" Folded Motion Tweeter and 2 x 4" poly cone woofers with rigid dust caps Woofer .
Frequency Response
Motion 30i has a frequency range of 65-25k Hz whereas Motion 8i has a frequency range of 70-23k Hz. With a minimum frequency of 65Hz, the Motion 30i 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 30i and Motion 8i have the same Impedance of 4 ohms but where they differ is the sensitivity levels. Motion 30i sensitivity is rated at 91 dB and the Motion 8i's is at 89 dB. This 2 dB difference makes the MartinLogan 30i 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 30i and the Motion 30i 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 30i can handle a max power of 200 watts RMS from the amp the whereas Motion 8i has a max power handling value of 180 watts RMS, 20 watts less than the Motion 30i.
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 30i features Spring post type posts and Motion 8i has a Spring post type posts. None of these speakers feature bi-amping/bi-wiring.
MartinLogan 30i's Custom 5-way tool-less binding posts terminals
MartinLogan 8i's Spring post terminals
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 30i's and MartinLogan 8i's external dimensions. MartinLogan 30i has external dimensions of 177.0 x 423.0 x 281.0mm ( 6-15/16 x 16-5/8 x 11-1/16inch) whereas 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) .
MartinLogan 8i is 35mm shorter and 147mm less deeper than MartinLogan 30i but it is also 139mm wider.
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 30i is approximately 1188.6cm2 / 184.2inch2 and base area of the MartinLogan 8i is approximately 753.1cm2 / 116.7inch2. The Motion 30i requires 58% more surface area than the Motion 8i 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 30i weighs 8.18kg / 18lbs and the MartinLogan 8i weighs 3.86kg / 8.5lbs. This makes the Motion 30i 112% heavier than the Motion 8i.
Here is a comparison of how Motion 30i and Motion 8i'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 30i?
Here are the items that are included inside the box of Motion 30i:
Center-channel loudspeaker Grille 4 Rubber feet Users Manual Warranty/Registration Information
What's in the Box of MartinLogan 8i?
Here are the items that come with the Motion 8i:
LCR loudspeakerGrille2 Wall-bracket2 Shoulder bolts4 Rubber bumpersCleaning clothUser-feets Manual (En/Fr)Installation templateProduct Registration Card
 Max Input Power |
200 watts
vs
180 watts
|
Handle more power from your amplifier |
 Sensitivity |
91 dB
vs
89 dB
|
Play louder with same amount of amplification power |
 Woofer Size |
5.25 inches
vs
4 inches
|
Larger woofer |
| Low Frequency Response |
65 Hz
vs
70 Hz
|
Generates deeper bass |
 High Frequency Response |
25k Hz
vs
23k Hz
|
Generates higher frequency |
| Number of Woofers |
2
vs
1
|
More woofers |
 Height |
142mm
vs
177mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
753cm2 (562x134mm)
vs
1188cm2 (423x281mm)
|
Takes less floor space |
 Price per pair* |
450USD
vs
900USD
|
costs less (*prices may change depending on the seller, location and time) |
| General |
MartinLogan Motion 30i |
MartinLogan Motion 8i |
| Brand |
MartinLogan |
MartinLogan |
| Speaker Type |
Center channel speaker |
Center channel speaker |
| Power Range |
20-200 watts |
20-180 watts |
| Sensitivity |
91 dB |
89 dB |
| Impedance |
4 ohms |
4 ohms |
| Frequency Response |
65-25k Hz |
70-23k Hz |
Drivers |
|
|
| Woofer Quantity |
1 |
2 |
| Woofer Size |
5.25" |
4" |
| Woofer Composition |
Aluminum |
poly cone woofers with rigid dust caps |
| Woofer Surround Material |
Rubber |
n/a |
| Tweeter Size |
1.0 x 1.4" |
1.0 x 1.4" |
| Tweeter Type |
Folded Motion |
Folded Motion |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
400Hz and 2600Hz |
n/a |
| Firing Direction |
rear |
n/a |
| 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 |
177.0mm (7") |
142.0mm (5.6") |
| Width |
423.0mm (16.7") |
562.0mm (22.1") |
| Depth |
281.0mm (11.1") |
134.0mm (5.3") |
| Weight |
8.18kg (18lbs) |
3.86kg (8.5lbs) |
| Enclosure |
Bass Reflex |
Passive Radiator |
| Finish |
MDF/Lacquer |
n/a |
| Available Colors |
White |
Gloss Black, Matt White, Red Walnut |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Biamp Inputs |
No |
n/a |
Other |
|
|
| Parts Warranty |
5 Years |
5 Yrs w/ Registration |
| Labor Warranty |
5 Years |
5 Yrs w/ Registration |