In this review, we will be comparing TSi400 and S55, two Passive Floor-standing speakers by Polk Audio Let's have a brief look at the main features
of Polk TSi400 and Polk S55 first before getting into our more
detailed comparison.
What size room are the Polk TSi400 and Polk S55 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 Polk TSi400 and Polk S55 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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through my links. As an Amazon Associate I earn from qualifying purchases.
Drivers
Both TSi400 and S55 are 2-way speakers.
| Driver |
Polk TSi400 |
Polk S55 |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
3 x 5.25-inch
|
2 x 6.5-inch
|
TSi400 features a 1" Tweeter and 3 x 5.25" Organic Fiber Woofer . On the other hand, the S55 features a 1" Terylene Dome Tweeter and 2 x 6.5" Mica-reinforced polypropylene Woofer with a Crossover frequency at 2500Hz.
Frequency Response
TSi400 has a frequency range of 44-24k Hz whereas S55 has a frequency range of 32-40k Hz. With a minimum frequency of 32Hz, the S55 can go significantly deeper on the low side and provide stronger bass compared to the TSi400's min frequency of 44Hz.
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
TSi400 and S55 have the same Impedance of 8 ohms but where they differ is the sensitivity levels. TSi400 sensitivity is rated at 91 dB and the S55's is at 90 dB. This 1 dB difference makes the Polk TSi400 a more sensitive speaker compared to Polk S55, 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.
TSi400 and S55 has the same power range of 20-200 watts.
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 TSi400 and S55 features dual binding post speaker terminals for bi-amping or bi-wiring.
Polk S55's 5-way post terminals allows Bi-amping or bi-wiring
Cabinet Type and Port Position
Both TSi400 and S55 have bottom firing ports.
Polk S55 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 Polk TSi400's and Polk S55's external dimensions. Polk TSi400 has external dimensions of 985.0 x 208.0 x 369.0mm ( 38-3/4 x 8-3/16 x 14-1/2inch) whereas Polk S55 has external dimensions of 1056.0 x 299.0 x 315.0mm ( 41-9/16 x 11-3/4 x 12-3/8inch) .
Polk TSi400 is 91mm narrower and 71mm shorter than Polk S55 but it is also 54mm deeper.
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 TSi400 is approximately 767.5cm2 / 119.0inch2 and base area of the Polk S55 is approximately 941.9cm2 / 146.0inch2. The TSi400 requires 19% less surface area than the S55 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 TSi400 weighs 14.55kg / 32lbs and the Polk S55 weighs 20.00kg / 44lbs. This makes the S55 37% heavier than the TSi400.
Here is a comparison of how TSi400 and S55'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 Polk TSi400?
Here are the items that are included inside the box of TSi400:
Tower speakerDetachable cloth grille (installed)Owners ManualWall-Mount templateOnline registration sheetPolk Audio product brochure
What's in the Box of Polk S55?
Here are the items that come with the S55:
Floorstanding loudspeakerGrille (attached)4 Feet (pre-installed)Owners ManualOnline Product Registration
 Sensitivity |
91 dB
vs
90 dB
|
Play louder with same amount of amplification power |
 Number of Woofers |
3
vs
2
|
More woofers |
 Height |
985mm
vs
1056mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
767cm2 (208x369mm)
vs
941cm2 (299x315mm)
|
Takes less floor space |
 Price per pair* |
498USD
vs
658USD
|
costs less (*prices may change depending on the seller, location and time) |
| Woofer Size |
6.5 inches
vs
5.25 inches
|
Larger woofer |
| Low Frequency Response |
32 Hz
vs
44 Hz
|
Generates deeper bass |
 High Frequency Response |
40k Hz
vs
24k Hz
|
Generates higher frequency |
| General |
Polk Audio TSi400 |
Polk Audio Signature S55 |
| Brand |
Polk Audio |
Polk Audio |
| Speaker Type |
Floor-standing speaker |
Floor-standing speaker |
| Power Range |
20-200 watts |
20-200 watts |
| Sensitivity |
91 dB |
90 dB |
| Impedance |
8 ohms |
8 ohms |
| Frequency Response |
44-24k Hz |
32-40k Hz |
Drivers |
|
|
| Woofer Quantity |
3 |
2 |
| Woofer Size |
5.25" |
6.5" |
| Woofer Composition |
Organic Fiber |
Mica-reinforced polypropylene |
| Woofer Surround Material |
Butyl Rubber |
Butyl rubber |
| Tweeter Size |
1" |
1" |
| Tweeter Type |
n/a |
Dome |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
n/a |
2500Hz |
| Firing Direction |
bottom |
bottom |
Physical Specs |
|
|
| Height |
985.0mm (38.8") |
1056.0mm (41.6") |
| Width |
208.0mm (8.2") |
299.0mm (11.8") |
| Depth |
369.0mm (14.5") |
315.0mm (12.4") |
| Weight |
14.55kg (32lbs) |
20.00kg (44lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Finish |
Wood-grain vinyl |
Meddite MDF |
| Available Colors |
Cherry |
Black |
| 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 |