In this review, we will be comparing Uni-Fi UB5 and S20, two Passive Bookshelf speakers from ELAC and Polk Audio. Let's have a brief look at the main features
of ELAC Uni-Fi UB5 and Polk S20 first before getting into our more
detailed comparison.
What size room are the ELAC Uni-Fi UB5 and Polk S20 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 ELAC Uni-Fi UB5 and Polk S20 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
One of the fundamental differences between these two speakers is that Uni-Fi UB5 is a 3-way design whereas the S20 is a 2-way speaker. 3-way designs utilize a midrange driver in addition to the tweeter and woofer on 2-way designs. Designing a crossover for a 3-way speaker is a complicated process and generally increases the overall cost of the speaker.
Driver |
ELAC Uni-Fi UB5 |
Polk S20 |
Driver Setup
|
3-way
|
2-way
|
Tweeter
|
1-inch
|
1-inch
|
Midrange
|
1 x 4-inch |
- |
Woofer
|
1 x 5.25-inch
|
1 x 6.5-inch
|
Uni-Fi UB5 features a 1" Soft-dome Tweeter , a 4" Midrange and 1 x 5.25" Aluminum Woofer with a Crossover frequency at 270Hz and 2700Hz. On the other hand, the S20 features a 1" Terylene Soft-Dome Tweeter and 1 x 6.5" Mica-reinforced polypropylene Woofer with a Crossover frequency at 2500Hz.
Frequency Response
Uni-Fi UB5 has a frequency range of 46-25k Hz whereas S20 has a frequency range of 39-40k Hz. With a minimum frequency of 39Hz, the S20 can go significantly deeper on the low side and provide stronger bass compared to the Uni-Fi UB5's min frequency of 46Hz.
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 Bookshelf class in our database.
Low Frequency
Bookshelf Speakers
High Frequency
Bookshelf 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
Uni-Fi UB5 is a 4 ohms speaker compared to the S20 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 Uni-Fi UB5 can provide this impedance level.
These two speakers also have different sensitivity levels. Uni-Fi UB5 sensitivity is rated at 85 dB and the S20's is rated at 88 dB. This 3 dB difference makes the Polk S20 a more sensitive speaker compared to ELAC Uni-Fi UB5, hence will play louder with the same amount of watts.
Sensitivity
Bookshelf 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.
Uni-Fi UB5 can handle a max power of 140 watts RMS from the amp the whereas S20 has a max power handling value of 125 watts RMS, 15 watts less than the Uni-Fi UB5.
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
Uni-Fi UB5 features 5-way post type posts and S20 has a 5-way post type posts. None of these speakers feature bi-amping/bi-wiring.
Cabinet Type and Port Position
Both Uni-Fi UB5 and S20 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.
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 ELAC Uni-Fi UB5's and Polk S20's external dimensions. ELAC Uni-Fi UB5 has external dimensions of 324.0 x 200.0 x 273.0mm ( 12.7 x 7.8 x 10.7inch) whereas Polk S20 has external dimensions of 376.0 x 216.0 x 350.0mm ( 14.8 x 8.5 x 13.7inch) .
Polk S20 is clearly the larger of the two speakers. Its body is 16mm wider, 52mm taller and 77mm deeper than ELAC Uni-Fi UB5.
Below you can see the front view size comparison of ELAC Uni-Fi UB5 and Polk S20 in scale.
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 ELAC Uni-Fi UB5 is approximately 546.0cm2 / 84.6inch2 and base area of the Polk S20 is approximately 756.0cm2 / 117.2inch2. The Uni-Fi UB5 requires 28% less surface area than the S20 which gives it a small advantage on placement in tight spaces.
Here is an another comparison that shows both speakers on a BDI Octave Media Cabinet, next to a standard size amplifier and turntable in scale:
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 ELAC Uni-Fi UB5 weighs 7.48kg / 16.5lbs and the Polk S20 weighs 7.73kg / 17lbs. This makes the S20 3% heavier than the Uni-Fi UB5.
Here is a comparison of how Uni-Fi UB5 and S20's weights compare with the average, max and min weights in Passive Bookshelf class.
Weight
All Bookshelf Speakers
What's in the Box of ELAC Uni-Fi UB5?
Here are the items that are included inside the box of Uni-Fi UB5:
2 Bookshelf loudspeakers 2 Grilles Operating Instructions
What's in the Box of Polk S20?
Here are the items that come with the S20:
2 Bookshelf loudspeakers2 Grilles (attached)8 Self-adhesive rubber feetOwners ManualOnline Product Registration
Max Input Power |
140 watts
vs
125 watts
|
Handle more power from your amplifier |
Driver Setup |
3-way
vs
2-way
|
Have a dedicated mid-range driver |
Height |
324mm
vs
376mm
|
Easier to fit in smaller spaces |
Base Surface Area |
546cm2 (200x273mm)
vs
756cm2 (216x350mm)
|
Takes less floor space |
Sensitivity |
88 dB
vs
85 dB
|
Play louder with same amount of amplification power |
Nominal Impedance |
8 ohms
vs
4 ohms
|
Less selective with amplifiers |
Woofer Size |
6.5 inches
vs
5.25 inches
|
Larger woofer |
Low Frequency Response |
39 Hz
vs
46 Hz
|
Generates deeper bass |
High Frequency Response |
40k Hz
vs
25k Hz
|
Generates higher frequency |
General |
ELAC Uni-Fi UB5 |
Polk Audio Signature S20 |
Brand |
ELAC |
Polk Audio |
Speaker Type |
Bookshelf speakers |
Bookshelf speakers |
Power Range |
40-140 watts |
20-125 watts |
Sensitivity |
85 dB |
88 dB |
Impedance |
4 ohms |
8 ohms |
Frequency Response |
46-25k Hz |
39-40k Hz |
Drivers |
|
|
Woofer Quantity |
1 |
1 |
Woofer Size |
5.25" |
6.5" |
Woofer Composition |
Aluminum |
Mica-reinforced polypropylene |
Woofer Surround Material |
Rubber |
Butyl rubber |
Tweeter Size |
1" |
1" |
Tweeter Type |
Soft-dome |
Soft-Dome |
Aimable Tweeter |
No |
No |
Midrange Driver |
4" |
No |
Crossover Frequency |
270Hz and 2700Hz |
2500Hz |
Firing Direction |
rear |
rear |
Physical Specs |
|
|
Height |
324.0mm (12.8") |
376.0mm (14.8") |
Width |
200.0mm (7.9") |
216.0mm (8.5") |
Depth |
273.0mm (10.7") |
350.0mm (13.8") |
Weight |
7.48kg (16.5lbs) |
7.73kg (17lbs) |
Enclosure |
Bass Reflex |
Bass Reflex |
Finish |
MDF/Vinyl |
Meddite MDF |
Available Colors |
Black |
Black, Walnut, Brown Walnut |
Mounting Bracket |
No |
No |
Recommended Stand Height |
24-31" |
24-28" |
Grille |
Yes |
Yes |
Moisture Resistancy |
No |
No |
Connections |
|
|
Biamp Inputs |
No |
No |
Other |
|
|
Parts Warranty |
3 Years |
5 Years |
Labor Warranty |
3 Years |
5 Years |