In this review, we will be comparing TSi400 and S50, two Passive Floor-standing speakers by Polk Audio.
Let's have a brief look at the main features
of Polk TSi400 and Polk S50 first before getting into our more
detailed comparison.
| Key Specs | Polk TSi400 | Polk S50 |
|---|
| Brand | Polk Audio
United States · founded 1972 | Polk Audio
United States · founded 1972 |
|---|
| Design | 2-way | 2-way |
|---|
| Tweeter | 1" | 1" Dome |
|---|
| Woofer | 3 x 5.25" Organic Fiber | 2 x 5.25" Mica-reinforced polypropylene |
|---|
| Frequency response | 44-24k Hz | 33-40k Hz |
|---|
| Sensitivity | 91 dB | 89 dB |
|---|
| Impedance | 8 ohms | 8 ohms |
|---|
| Power range | 20-200 watts | 20-150 watts |
|---|
| Weight | 14.55kg / 32lbs | 14.50kg / 31.9lbs |
|---|
| Dimensions (H x W x D) | 38-3/4" x 8-3/16" x 14-1/2"
985.0 x 208.0 x 369.0mm | 37-7/16" x 10-5/16" x 11-1/16"
951.0 x 262.0 x 281.0mm |
|---|
What size room are the Polk TSi400 and Polk S50 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 TSi400 |
Polk S50 |
| Near-field |
Bad |
Bad |
| Small Room |
Poor |
Poor |
| Mid-size Room |
Good |
Good |
| Large Room |
Good |
Good |
| 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.)
The sections below take each area in turn: drivers, frequency response, physical size and what you get in the box.
Drivers
Both TSi400 and S50 are 2-way speakers.
Polk TSi400Polk S50
TweeterWoofer
Front view, drawn to scale - cabinets and drivers share one scale, so sizes are directly comparable. Hover a driver for its size.
| Driver |
Polk TSi400 |
Polk S50 |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
3 x 5.25-inch
|
2 x 5.25-inch
|
TSi400 features a 1" Tweeter and 3 x 5.25" Organic Fiber Woofer. On the other hand, the S50 features a 1" Terylene Dome Tweeter and 2 x 5.25" Mica-reinforced polypropylene Woofer with a Crossover frequency at 2500Hz.
Frequency Response
TSi400 has a frequency range of 44-24k Hz whereas S50 has a frequency range of 33-40k Hz. With a minimum frequency of 33Hz, the S50 can go significantly deeper on the low side and provide stronger bass compared to the TSi400's min frequency of 44Hz.
The graph below depicts how these two speakers compare with the max, min and average Low Frequency values of other speakers in the Floor-standing class in our database.
Low Frequency
Floor-standing Speakers
Neither pair reaches down to 20Hz, the usual definition of full-range, which is normal for speakers of this size. If you want the bottom octave for movies or bass-heavy music, add a subwoofer to whichever you choose. Visit our Powered Subwoofers section to find out more about the available options.
Impedance and Sensitivity
TSi400 and S50 have the same Impedance of 8 ohms but where they differ is the sensitivity levels. TSi400 sensitivity is rated at 91 dB and the S50's is at 89 dB. This 2 dB difference makes the Polk TSi400 a more sensitive speaker compared to Polk S50, 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. Staying
within that range gives nominal performance; driving the speaker beyond its maximum wattage can damage it.
TSi400 can handle a max power of 200 watts RMS, whereas S50 has a max power handling value of 150 watts RMS, 50 watts less than the TSi400.
Note that higher power handling does not make a speaker louder: that depends mainly on
sensitivity and impedance. The calculator below shows how loud each of these actually plays
on a real amplifier.
Which plays louder on your amplifier?
Starting with a popular amplifier - change it to the one you own, or any you are
considering, and watch both numbers move.
Input Type and Bi-Amping / Bi-Wiring
Both TSi400 and S50 features dual binding post speaker terminals for bi-amping or bi-wiring.
Polk S50's 5-way post terminals allows Bi-amping or bi-wiring
Cabinet Type and Port Position
Both TSi400 and S50 have bottom firing ports.
Polk S50 Port
Physical Specs
The size of a speaker can sometimes be 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 S50'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 S50 has external dimensions of 951.0 x 262.0 x 281.0mm (37-7/16 x 10-5/16 x 11-1/16inch).
Polk S50 is 34mm shorter and 88mm less deeper than Polk TSi400 but it is also 54mm 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 Polk TSi400 is approximately 767.5cm2 / 119.0inch2 and base area of the Polk S50 is approximately 736.2cm2 / 114.1inch2. The TSi400 requires 4% more surface area than the S50 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 Polk TSi400 weighs 14.55kg / 32lbs and the Polk S50 weighs 14.50kg / 31.9lbs. This makes the TSi400 0% heavier than the S50.
Here is a comparison of how TSi400 and S50'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 speaker
- Detachable cloth grille (installed)
- Owners Manual
- Wall-Mount template
- Online registration sheet
- Polk Audio product brochure
What's in the Box of Polk S50?
Here are the items that come with the S50:
- Floorstanding loudspeaker
- Grille (attached)
- 4 Feet (pre-installed)
- Owners Manual
- Online Product Registration
 Max Input Power |
200 watts
vs
150 watts
|
Handle more power from your amplifier |
 Sensitivity |
91 dB
vs
89 dB
|
Play louder with same amount of amplification power |
 Number of Woofers |
3
vs
2
|
More woofers |
|
Low Frequency Response |
33 Hz
vs
44 Hz
|
Generates deeper bass |
 High Frequency Response |
40k Hz
vs
24k Hz
|
Generates higher frequency |
 Height |
951mm
vs
985mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
736cm2
vs
767cm2
|
Takes less floor space |
| General |
Polk Audio TSi400 |
Polk Audio Signature S50 |
| Brand |
Polk Audio |
Polk Audio |
| Speaker Type |
Floor-standing speaker |
Floor-standing speaker |
| Power Range |
20-200 watts |
20-150 watts |
| Sensitivity |
91 dB |
89 dB |
| Impedance |
8 ohms |
8 ohms |
| Frequency Response |
44-24k Hz |
33-40k Hz |
Drivers |
|
|
| Woofer Quantity |
3 |
2 |
| Woofer Size |
5.25" |
5.25" |
| 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") |
951.0mm (37.4") |
| Width |
208.0mm (8.2") |
262.0mm (10.3") |
| Depth |
369.0mm (14.5") |
281.0mm (11.1") |
| Weight |
14.55kg (32lbs) |
14.50kg (31.9lbs) |
| 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 |
A generation apart: Polk S50 is the newer design, against a 2011 model. Newer is not automatically better, but the older one is more likely to be discounted or near run-out.
| Area | Better | Why |
|---|
| Bass | B | Polk S50 digs deeper - 33Hz against 44Hz. |
| Amplifier needs | A | Polk TSi400 is more sensitive (91dB vs 89dB), so it goes louder on the same amplifier. |
| Headroom | A | Polk TSi400 takes more power (200W vs 150W) - more in hand in a big room. |
| Size | depends | Similar cabinet size - neither is easier to fit. |
| Expandability | depends | Polk TSi400: bi-amping; Polk S50: bi-amping. |
| Price | evenly matched | Much the same money ($498 vs $498 a pair). |
A Polk TSi400 B Polk S50
depends neither is better in the abstract - it turns on your room, your system or how you will use them. Only specs published for both speakers are judged; anything missing on either side is left out rather than guessed.
Which should you choose?
Polk TSi400 has the edge on paper, though the margin is not large. The rows marked "depends" may matter more to you than the score does. If a subwoofer is in your plans, the bass gap largely stops mattering - you would be crossing over above 44Hz anyway, so judge these on the other rows instead. If your amplifier is modest, vintage or valve-based, Polk TSi400 is the safer partner - the other will want more current or more watts to sound its best.
And remember what a spec sheet cannot show: how each looks in your room and whether the finish suits it, what dealer support and warranty are like where you live, and how they actually sound to you. If you can hear them first - ideally with your own music - that will tell you more than any number above.