In this review, we will be comparing Blackstone TL1 and Motion 6i, two Passive Center Channel speakers from Polk Audio and MartinLogan.
Let's have a brief look at the main features
of Polk TL1 and MartinLogan 6i first before getting into our more
detailed comparison.
Polk TL1 Key Specs
- 2-way Design
- 0.5" dome Tweeter
- 2 x 2.5" Dynamic Balance Woofer
- 125-20k Hz Frequency Response
- 89 dB Sensitivity
- Impedance: 8ohms
- Power Range:10-125watts
- Weight:1.84kg
- Dimensions (H x W x D): 101.0" x 15" x 3-7/16"( 101.0 x 381.0 x 88.0mm )
MartinLogan 6i Key Specs
- 2-way Design
- 1.0 x 1.0" Folded Motion Tweeter
- 2 x 3.5" poly cone woofers with rigid dust caps Woofer
- 120-23k Hz Frequency Response
- 89 dB Sensitivity
- Impedance: 6ohms
- Power Range:20-130watts
- Weight:2.59kg
- Dimensions (H x W x D): 134.0" x 17-1/2" x 4"( 134.0 x 445.0 x 102.0mm )
What size room are the Polk TL1 and MartinLogan 6i 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* |
Polk TL1 |
MartinLogan 6i |
| Near-field |
Poor |
Poor |
| Small Room |
Average |
Average |
| Mid-size Room |
Good |
Good |
| Large Room |
Average |
Average |
| Very Large Room |
Poor |
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.)
In the following sections, we will get into more detail in order to better understand how the Polk TL1 and MartinLogan 6i 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
Both Blackstone TL1 and Motion 6i are 2-way speakers.
| Driver |
Polk TL1 |
MartinLogan 6i |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
0.5-inch
|
1.0 x 1.0-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
2 x 2.5-inch
|
2 x 3.5-inch
|
Blackstone TL1 features a 0.5" silk dome Tweeter and 2 x 2.5" Dynamic Balance Woofer . On the other hand, the Motion 6i features a 1.0 x 1.0" Folded Motion Tweeter and 2 x 3.5" poly cone woofers with rigid dust caps Woofer .
Frequency Response
Blackstone TL1 has a frequency range of 125-20k Hz whereas Motion 6i has a frequency range of 120-23k Hz. With a minimum frequency of 120Hz, the Motion 6i can go significantly deeper on the low side and provide stronger bass compared to the Blackstone TL1's min frequency of 125Hz.
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
Blackstone TL1 is a 8 ohms speaker compared to the Motion 6i which has a nominal impedance of 6 ohms.
On the other hand, they have the same sensitivity of 89 dBdB.
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.
Blackstone TL1 can handle a max power of 130 watts RMS from the amp the whereas Blackstone TL1 has a max power handling value of 125 watts RMS , 5 watts less than the Motion 6i.
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
Blackstone TL1 features Spring post type posts and Motion 6i has a Spring post type posts. None of these speakers feature bi-amping/bi-wiring.
MartinLogan 6i'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 Polk TL1's and MartinLogan 6i's external dimensions. Polk TL1 has external dimensions of 101.0 x 381.0 x 88.0mm ( 3-15/16 x 15 x 3-7/16inch) whereas MartinLogan 6i has external dimensions of 134.0 x 445.0 x 102.0mm ( 5-1/4 x 17-1/2 x 4inch) .
MartinLogan 6i is clearly the larger of the two speakers. Its body is 64mm wider, 33mm taller and 14mm deeper than Polk TL1.
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 Polk TL1 is approximately 335.3cm2 / 52.0inch2 and base area of the MartinLogan 6i is approximately 453.9cm2 / 70.4inch2. The Blackstone TL1 requires 26% less surface area than the Motion 6i 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 Polk TL1 weighs 1.84kg / 4lbs and the MartinLogan 6i weighs 2.59kg / 5.7lbs. This makes the Motion 6i 41% heavier than the Blackstone TL1.
Here is a comparison of how Blackstone TL1 and Motion 6i'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 Polk TL1?
Here are the items that are included inside the box of Blackstone TL1:
Gloss-black center-channel loudspeakerDetachable black cloth grille (attached)System Diagram/Warranty sheetTemplateOnline Product Registration cardImportant Safety Instructions
What's in the Box of MartinLogan 6i?
Here are the items that come with the Motion 6i:
LCR loudspeakerGrille2 Wall-bracket2 Shoulder bolts4 Rubber bumpersCleaning clothUser-feets Manual (En/Fr)Installation templateProduct Registration Card
 Nominal Impedance |
8 ohms
vs
6 ohms
|
Less selective with amplifiers |
 Height |
101mm
vs
134mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
335cm2
vs
453cm2
|
Takes less floor space |
 Price per pair* |
79USD
vs
300USD
|
costs less (*prices may change depending on the seller, location and time) |
 Max Input Power |
130 watts
vs
125 watts
|
Handle more power from your amplifier |
 Woofer Size |
3.5 inches
vs
2.5 inches
|
Larger woofer |
|
Low Frequency Response |
120 Hz
vs
125 Hz
|
Generates deeper bass |
 High Frequency Response |
23k Hz
vs
20k Hz
|
Generates higher frequency |
| General |
Polk Audio Blackstone TL1 |
MartinLogan Motion 6i |
| Brand |
Polk Audio |
MartinLogan |
| Speaker Type |
Center channel speaker |
Center channel speaker |
| Power Range |
10-125 watts |
20-130 watts |
| Sensitivity |
89 dB |
89 dB |
| Impedance |
8 ohms |
6 ohms |
| Frequency Response |
125-20k Hz |
120-23k Hz |
Drivers |
|
|
| Woofer Quantity |
2 |
2 |
| Woofer Size |
2.5" |
3.5" |
| Woofer Composition |
Dynamic Balance |
poly cone woofers with rigid dust caps |
| Tweeter Size |
0.5" |
1.0 x 1.0" |
| Tweeter Type |
dome |
Folded Motion |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Firing Direction |
rear |
n/a |
| Suggested Break-in Period |
n/a |
Allow 72 hours of break-in at 90 dB |
Physical Specs |
|
|
| Height |
101.0mm (4") |
134.0mm (5.3") |
| Width |
381.0mm (15") |
445.0mm (17.5") |
| Depth |
88.0mm (3.5") |
102.0mm (4") |
| Weight |
1.84kg (4lbs) |
2.59kg (5.7lbs) |
| Enclosure |
Bass Reflex |
Passive Radiator |
| Available Colors |
Gloss Black |
Gloss Black, Matt White, Red Walnut |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
5 Years |
5 Yrs w/ Registration |
| Labor Warranty |
5 Years |
5 Yrs w/ Registration |