In this review, we will be comparing L400 and Ultra Center, two Passive Center Channel speakers from Polk Audio and SVS. Let's have a brief look at the main features
of Polk L400 and SVS Ultra Center first before getting into our more
detailed comparison.
What size room are the Polk L400 and SVS Ultra Center 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 L400 and SVS Ultra Center 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 L400 and Ultra Center are 3-way speakers.
| Driver |
Polk L400 |
SVS Ultra Center |
|
Driver Setup
|
3-way
|
3-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
1 x 4-inch |
1 x 4-inch |
|
Woofer
|
2 x 6.5-inch
|
2 x 6.5-inch
|
L400 features a 1" Pinnacle Ring Radiator Tweeter , a 4" Midrange and 2 x 6.5" Woofer . On the other hand, the Ultra Center features a 1" aluminum Dome Tweeter , a 4" Midrange and 2 x 6.5" composite glass-fiber Woofer with a Crossover frequency at 500Hz and 2200Hz.
Frequency Response
L400 has a frequency range of 55-38k Hz whereas Ultra Center has a frequency range of 45-32k Hz. With a minimum frequency of 45Hz, the Ultra Center can go significantly deeper on the low side and provide stronger bass compared to the L400's min frequency of 55Hz.
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
L400 is a 4 ohms speaker compared to the Ultra Center which has a nominal impedance of 8 ohms. Lower impedance speakers, especially the ones that are rated at 4 ohms may put more pressure on the amplifier unit especially when played at high volume levels, so make sure the amp you pair with the L400 can provide this impedance level.
These two speakers also have different sensitivity levels. L400 sensitivity is rated at 87.5 dB and the Ultra Center's is rated at 87 dB. This 1 dB difference makes the Polk L400 a more sensitive speaker compared to SVS Ultra Center, hence will play louder with the same amount of watts.
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.
L400 can handle a max power of 300 watts RMS from the amp the whereas Ultra Center has a max power handling value of 225 watts RMS, 75 watts less than the L400.
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
Ultra Center features 5-Way post posts which make bi-amping or bi-wiring possible. L400 has a Binding post which doesn't feature bi-amping/bi-wiring.
Polk L400's Binding post terminals
SVS Ultra Center's 5-Way post terminals allows Bi-amping or bi-wiring
Cabinet Type and Port Position
Both L400 and Ultra Center have rear firing ports. Rear ported speakers generally need more room between the backside of the speaker and the wall compared to sealed and front/bottom ported speakers. Placing the speakers too close to the walls may cause the bass to sound boomy.
If you are limited in space and can't get the speakers away from the backwall, check our Speakers with Front Firing Ports page.
Polk L400 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 L400's and SVS Ultra Center's external dimensions. Polk L400 has external dimensions of 245.0 x 662.0 x 343.0mm ( 9-5/8 x 26-1/16 x 13-1/2inch) whereas SVS Ultra Center has external dimensions of 207.0 x 561.0 x 285.0mm ( 8-1/8 x 22-1/16 x 11-3/16inch) .
Polk L400 is clearly the larger of the two speakers. Its body is 101mm wider, 38mm taller and 58mm deeper than SVS Ultra Center.
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 L400 is approximately 2270.7cm2 / 352.0inch2 and base area of the SVS Ultra Center is approximately 1598.9cm2 / 247.8inch2. The L400 requires 42% more surface area than the Ultra Center 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 L400 weighs 18.55kg / 40.8lbs and the SVS Ultra Center weighs 14.09kg / 31lbs. This makes the L400 32% heavier than the Ultra Center.
Here is a comparison of how L400 and Ultra Center'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 L400?
Here are the items that are included inside the box of L400:
Center-channel loudspeakerGrille2 Jumper-wiresCleaning clothOwners ManualOnline Registration
What's in the Box of SVS Ultra Center?
Here are the items that come with the Ultra Center:
Center channel loudspeakerGrille2 Terminal jumpers (pre-installed)4 Rubber feetOwners ManualSVS brochureOnline Product Registration Card
 Max Input Power |
300 watts
vs
225 watts
|
Handle more power from your amplifier |
 Sensitivity |
88 dB
vs
87 dB
|
Play louder with same amount of amplification power |
 High Frequency Response |
38k Hz
vs
32k Hz
|
Generates higher frequency |
 Nominal Impedance |
8 ohms
vs
4 ohms
|
Less selective with amplifiers |
 Low Frequency Response |
45 Hz
vs
55 Hz
|
Generates deeper bass |
 Height |
207mm
vs
245mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1598cm2 (561x285mm)
vs
2270cm2 (662x343mm)
|
Takes less floor space |
 Price per pair* |
799USD
vs
1799USD
|
costs less (*prices may change depending on the seller, location and time) |
| General |
Polk Audio Legend L400 |
SVS Ultra Center |
| Brand |
Polk Audio |
SVS |
| Speaker Type |
Center channel speaker |
Center channel speaker |
| Power Range |
25-300 watts |
20-225 watts |
| Sensitivity |
87.5 dB |
87 dB |
| Impedance |
4 ohms |
8 ohms |
| Frequency Response |
55-38k Hz |
45-32k Hz |
Drivers |
|
|
| Woofer Quantity |
2 |
2 |
| Woofer Size |
6.5" |
6.5" |
| Woofer Composition |
|
composite glass-fiber |
| Woofer Surround Material |
n/a |
Rubber |
| Tweeter Size |
1" |
1" |
| Tweeter Type |
Pinnacle Ring Radiator |
Dome |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
4" |
4" |
| Crossover Frequency |
n/a |
500Hz and 2200Hz |
| Firing Direction |
rear |
rear |
Physical Specs |
|
|
| Height |
245.0mm (9.6") |
207.0mm (8.1") |
| Width |
662.0mm (26.1") |
561.0mm (22.1") |
| Depth |
343.0mm (13.5") |
285.0mm (11.2") |
| Weight |
18.55kg (40.8lbs) |
14.09kg (31lbs) |
| Enclosure |
Bass Reflex |
Bass Reflex |
| Available Colors |
Black, Walnut |
Black Oak,Piano Gloss Black,Piano Gloss White |
| Grille |
Yes |
Yes |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Biamp Inputs |
n/a |
Yes |
Other |
|
|
| Parts Warranty |
5 Years |
5 Years |
| Labor Warranty |
5 Years |
5 Years |