In this review, we will be comparing Theva Center and Q650c, two Passive Center Channel speakers from Focal and KEF. Let's have a brief look at the main features
of Focal Theva Center and KEF Q650c first before getting into our more
detailed comparison.
What size room are the Focal Theva Center and KEF Q650c 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 Focal Theva Center and KEF Q650c 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
Both Theva Center and Q650c are 2-way speakers.
| Driver |
Focal Theva Center |
KEF Q650c |
|
Driver Setup
|
2-way
|
2-way
|
|
Tweeter
|
1-inch
|
1-inch
|
|
Midrange
|
- |
- |
|
Woofer
|
2 x 6.5-inch
|
2 x 6.5-inch
|
Theva Center features a 1" TNF Al/Mg inverted dome Tweeter and 2 x 6.5" Slatefiber Woofer with a Crossover frequency at 2100 Hz. On the other hand, the Q650c features a 1" vented aluminum Dome Tweeter and 2 x 6.5" aluminum Woofer with a Crossover frequency at 2500Hz.
Frequency Response
Theva Center has a frequency range of 59-28kHz whereas Q650c has a frequency range of 64-28k Hz. With a minimum frequency of 59Hz, the Theva Center can go significantly deeper on the low side and provide stronger bass compared to the Q650c's min frequency of 64Hz.
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
Theva Center and Q650c have the same Impedance of 8 ohms but where they differ is the sensitivity levels. Theva Center sensitivity is rated at 91 dB and the Q650c's is at 87 dB. This 4 dB difference makes the Focal Theva Center a more sensitive speaker compared to KEF Q650c, 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.
Theva Center can handle a max power of 200 watts RMS from the amp the whereas Q650c has a max power handling value of 150 watts RMS, 50 watts less than the Theva Center.
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
Theva Center features Binding post posts which make bi-amping or bi-wiring possible. Q650c has a Binding post which doesn't feature bi-amping/bi-wiring.
KEF Q650c's Binding post terminals
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 Focal Theva Center's and KEF Q650c's external dimensions. Focal Theva Center has external dimensions of 210.0 x 531.0 x 254.0mm ( 81/4 x 207/8 x 10) whereas KEF Q650c has external dimensions of 212.0 x 631.0 x 304.0mm ( 8-5/16 x 24-13/16 x 11-15/16inch) .
KEF Q650c is clearly the larger of the two speakers. Its body is 100mm wider, 2mm taller and 50mm deeper than Focal Theva 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 Focal Theva Center is approximately 1348.7cm2 / 209.0inch2 and base area of the KEF Q650c is approximately 1918.2cm2 / 297.3inch2. The Theva Center requires 30% less surface area than the Q650c 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 Focal Theva Center weighs 10.00kg / 22lbs and the KEF Q650c weighs 13.64kg / 30lbs. This makes the Q650c 36% heavier than the Theva Center.
Here is a comparison of how Theva Center and Q650c'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 KEF Q650c?
Here are the items that come with the Q650c:
Center-channel loudspeaker 4 Self-adhesive rubber feet Owners Manual Warranty Information
 Max Input Power |
200 watts
vs
150 watts
|
Handle more power from your amplifier |
 Sensitivity |
91 dB
vs
87 dB
|
Play louder with same amount of amplification power |
 Low Frequency Response |
59 Hz
vs
64 Hz
|
Generates deeper bass |
 Height |
210mm
vs
212mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1348cm2 (531x254mm)
vs
1918cm2 (631x304mm)
|
Takes less floor space |
 Price per pair* |
649USD
vs
750USD
|
costs less (*prices may change depending on the seller, location and time) |
 Minimum Impedance |
4.2 ohms
vs
3.8 ohms
|
Very low impedance levels puts more pressure on amplifier |
| Passive Radiator |
one 6.5-inch
vs
None
|
Increases the bass performance |
| General |
Focal Theva Center |
KEF Q650c |
| Brand |
Focal |
KEF |
| Speaker Type |
Center channel speaker |
Center channel speaker |
| Power Range |
40-200 watts |
15-150 watts |
| Sensitivity |
91 dB |
87 dB |
| Impedance |
8 ohms |
8 ohms |
| Impedance |
3.8 ohms |
4.2 ohms |
| Frequency Response |
59-28kHz |
64-28k Hz |
Drivers |
|
|
| Woofer Quantity |
2 |
2 |
| Woofer Size |
6.5" |
6.5" |
| Woofer Composition |
Slatefiber |
aluminum |
| Woofer Surround Material |
Rubber |
Rubber |
| Tweeter Size |
1" |
1" |
| Tweeter Type |
inverted dome |
Dome |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
2100 Hz |
2500Hz |
Physical Specs |
|
|
| Height |
210.0mm (8.3") |
212.0mm (8.3") |
| Width |
531.0mm (20.9") |
631.0mm (24.8") |
| Depth |
254.0mm (10") |
304.0mm (12") |
| Weight |
10.00kg (22lbs) |
13.64kg (30lbs) |
| Enclosure |
Acoustic Suspension |
Passive Radiator |
| Available Colors |
Black High Gloss,Dark Wood,Light Wood |
Satin White, Satin Black, Walnut |
| Grille |
Yes |
optional |
| Moisture Resistancy |
No |
No |
Connections |
|
|
| Biamp Inputs |
Yes |
n/a |
Other |
|
|
| Parts Warranty |
5 Years |
5 Years |
| Labor Warranty |
5 Years |
5 Years |