In this review, we will be comparing Lumina III and S50, two Passive Floor-standing speakers from Sonus Faber and Polk Audio. Let's have a brief look at the main features
of Sonus Lumina III and Polk S50 first before getting into our more
detailed comparison.
What size room are the Sonus Lumina III 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:
In the following sections, we will get into more detail in order to better understand how the Sonus Lumina III and Polk S50 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
One of the fundamental differences between these two speakers is that Lumina III is a 3-way design whereas the S50 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 |
Sonus Lumina III |
Polk S50 |
Driver Setup
|
3-way
|
2-way
|
Tweeter
|
1.15-inch
|
1-inch
|
Midrange
|
1 x 6-inch |
- |
Woofer
|
2 x 6-inch
|
2 x 5.25-inch
|
Lumina III features a 1.15" high definition DAD Tweeter , a 6" Midrange and 2 x 6" paper cone Woofer with a Crossover frequency at 350 and 3500 Hz. 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
Lumina III has a frequency range of 40-24k 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 Lumina III's min frequency of 40Hz.
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
Lumina III is a 4 ohms speaker compared to the S50 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 Lumina III can provide this impedance level.
On the other hand, they have the same sensitivity of 89 dBdB.
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.
Lumina III can handle a max power of 250 watts RMS from the amp the whereas S50 has a max power handling value of 150 watts RMS, 100 watts less than the Lumina III.
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 Lumina III and S50 features dual binding post speaker terminals for bi-amping or bi-wiring.
Cabinet Type and Port Position
Both Lumina III and S50 have bottom firing ports.
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 Sonus Lumina III's and Polk S50's external dimensions. Sonus Lumina III has external dimensions of 989.0 x 228.0 x 278.0mm ( 38.9 x 9 x 10.9inch) 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) .
Sonus Lumina III is 34mm narrower and 3mm less deeper than Polk S50 but it is also 38mm taller.
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 Sonus Lumina III is approximately 633.8cm2 / 98.2inch2 and base area of the Polk S50 is approximately 736.2cm2 / 114.1inch2. The Lumina III requires 14% less surface area than the S50 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 Sonus Lumina III weighs 15.90kg / 35lbs and the Polk S50 weighs 14.50kg / 31.9lbs. This makes the Lumina III 10% heavier than the S50.
Here is a comparison of how Lumina III 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 Sonus Lumina III?
Here are the items that are included inside the box of Lumina III:
Floorstanding loudspeaker1 Manual 2 Jumpers2 Grilles 2 Fabric dust guards4 Spikes 4 Under spikes 4 Spikes locks
What's in the Box of Polk S50?
Here are the items that come with the S50:
Floorstanding loudspeakerGrille (attached)4 Feet (pre-installed)Owners ManualOnline Product Registration
Max Input Power |
250 watts
vs
150 watts
|
Handle more power from your amplifier |
Driver Setup |
3-way
vs
2-way
|
Have a dedicated mid-range driver |
Woofer Size |
6 inches
vs
5.25 inches
|
Larger woofer |
Base Surface Area |
633cm2 (228x278mm)
vs
736cm2 (262x281mm)
|
Takes less floor space |
Nominal Impedance |
8 ohms
vs
4 ohms
|
Less selective with amplifiers |
Low Frequency Response |
33 Hz
vs
40 Hz
|
Generates deeper bass |
High Frequency Response |
40k Hz
vs
24k Hz
|
Generates higher frequency |
Height |
951mm
vs
989mm
|
Easier to fit in smaller spaces |
General |
Sonus Faber Lumina III |
Polk Audio Signature S50 |
Brand |
Sonus Faber |
Polk Audio |
Speaker Type |
Floor-standing speaker |
Floor-standing speaker |
Power Range |
50-250 watts |
20-150 watts |
Sensitivity |
89 dB |
89 dB |
Impedance |
4 ohms |
8 ohms |
Frequency Response |
40-24k Hz |
33-40k Hz |
Drivers |
|
|
Woofer Quantity |
2 |
2 |
Woofer Size |
6" |
5.25" |
Woofer Composition |
paper cone |
Mica-reinforced polypropylene |
Woofer Surround Material |
n/a |
Butyl rubber |
Tweeter Size |
1.15" |
1" |
Tweeter Type |
high definition DAD |
Dome |
Aimable Tweeter |
No |
No |
Midrange Driver |
6" |
No |
Crossover Frequency |
350 and 3500 Hz |
2500Hz |
Firing Direction |
bottom |
bottom |
Physical Specs |
|
|
Height |
989.0mm (38.9") |
951.0mm (37.4") |
Width |
228.0mm (9") |
262.0mm (10.3") |
Depth |
278.0mm (10.9") |
281.0mm (11.1") |
Weight |
15.90kg (35lbs) |
14.50kg (31.9lbs) |
Enclosure |
Bass Reflex |
Bass Reflex |
Finish |
real multilayer wood |
Meddite MDF |
Available Colors |
Black, Wenge, Walnut |
Black |
Grille |
Yes |
Yes |
Moisture Resistancy |
No |
No |
Connections |
|
|
Biamp Inputs |
Yes |
Yes |
Other |
|
|
Parts Warranty |
|
5 Years |
Labor Warranty |
|
5 Years |