In this review, we will be comparing C-308ASWi and KUBE 8b, two Powered Subwoofer speakers from Klipsch and KEF. Being Powered subwoofers, they both have built-in amplifiers so you don't need an external power amp or an integrated amp to power them. Let's have a brief look at the main features of Klipsch C-308ASWi and KEF KUBE 8b first before getting into our more detailed comparison.
In the following sections, we will get into details in order to better understand how the Klipsch C-308ASWi and KEF KUBE 8b compare and hopefully end up with enough arguments to decide which one of these subwoofers 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
The efficiency of a subwoofer is directly proportional to the total radiating are squared hence the woofer quantity and diameter.Klipsch C-308ASWiand KEF KUBE 8b have the same driver set up: Both subwoofers have 1 x 8" drivers.
Frequency Response
C-308ASWi has a frequency range of 28-150 Hz whereas KUBE 8b has a frequency range of 34-140 Hz. With a minimum frequency of 28Hz, the C-308ASWi can go significantly deeper on the low side and provide stronger bass compared to the KUBE 8b's min frequency of 34Hz.
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 Subwoofer class in our database.
Low Frequency
Subwoofer Speakers
High Frequency
Subwoofer Speakers
Cabinet Type
The Klipsch C-308ASWi has a Passive Radiator type cabinet. Passive Radiator type subwoofers sports a non-powered cone that moves in response to the main woofer to move air out in order to generate stronger bass in a smaller body compared to ported or sealed designs. On the other hand the KEF KUBE 8b have Acoustic Suspension type enclosure. Acoustic Suspension aka Sealed type subwoofers have enclosures that are sealed hence no ports or holes exists on the cabinet. Sealed designs helps to provide more accurate and tight bass responses compared to ported designs.
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 Klipsch C-308ASWi's and KEF KUBE 8b's external dimensions. Klipsch C-308ASWi has external dimensions of 299.0 x 286.0 x 356.0mm ( 11-3/4 x 11-1/4 x 14inch) whereas KEF KUBE 8b has external dimensions of 294.0 x 296.0 x 339.0mm ( 11-9/16 x 11-5/8 x 13-5/16inch) .
KEF KUBE 8b is 5mm shorter and 17mm less deeper than Klipsch C-308ASWi but it is also 10mm wider.
Below you can see the front view size comparison of Klipsch C-308ASWi and KEF KUBE 8b in scale.
Comparison image of Klipsch C-308ASWi and KEF KUBE 8b Size and External Dimensions
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 Klipsch C-308ASWi is approximately 1018.2cm2 / 157.8inch2 and base area of the KEF KUBE 8b is approximately 1003.4cm2 / 155.5inch2. The C-308ASWi requires 1% more surface area than the KUBE 8b which gives it a small disadvantage on placement in tight spaces.
Weight Comparison The weight of a subwoofer may become an important factor if you need to move and reposition the unit often to find the optimal positioning, also known as 'Subwoofer Crawling'. The Klipsch C-308ASWi weighs 12.27kg / 27lbs and the KEF KUBE 8b weighs 11.36kg / 25lbs. This makes the C-308ASWi 8% heavier than the KUBE 8b.
Here is a comparison of how C-308ASWi and KUBE 8b's weights compare with the average, max and min weights in Powered Subwoofer class.
Weight
All Subwoofer Speakers
What's in the Box of Klipsch C-308ASWi?
Here are the items that are included inside the box of C-308ASWi:
Powered subwooferGrille8-feet AC power cordUser Manual
What's in the Box of KEF KUBE 8b?
Here are the items that come with the KUBE 8b:
Powered subwoofer6.5-feet AC power cordSpeaker-level input blockUser ManualImportant Safety InformationWarranty Information
 Low Frequency Response |
28 Hz
vs
34 Hz
|
Generates deeper bass |
 High Frequency Response |
150k Hz
vs
140k Hz
|
Generates higher frequency |
 Wireless Operation |
Optional
vs
No
|
Connect your subwoofer to your system wireless |
 Height |
294mm
vs
299mm
|
Easier to fit in smaller spaces |
 Base Surface Area |
1003cm2 (296x339mm)
vs
1018cm2 (286x356mm)
|
Takes less floor space |
| General |
Klipsch C Series C-308ASWi |
KEF KUBE 8b |
| Brand |
Klipsch |
KEF |
| Speaker Type |
Powered Subwoofer |
Powered Subwoofer |
| Max Amplifier Output |
300 watts |
300 watts |
| Frequency Response |
28-150 Hz |
34-140 Hz |
Amplifier |
|
|
| Watts RMS (Continuous) |
300-watt RMS |
300-watt RMS |
Drivers |
|
|
| Woofer Quantity |
1 |
1 |
| Woofer Size |
8" |
8" |
| Woofer Composition |
Cerametallic |
Not given |
| Tweeter Size |
- |
- |
| Aimable Tweeter |
No |
No |
| Midrange Driver |
No |
No |
| Crossover Frequency |
n/a |
40-140 Hz |
| Firing Direction |
front |
front |
Physical Specs |
|
|
| Height |
299.0mm (11.8") |
294.0mm (11.6") |
| Width |
286.0mm (11.3") |
296.0mm (11.7") |
| Depth |
356.0mm (14") |
339.0mm (13.3") |
| Weight |
12.27kg (27lbs) |
11.36kg (25lbs) |
| Enclosure |
Passive Radiator |
Acoustic Suspension |
| Grille |
Yes |
n/a |
| Moisture Resistancy |
No |
No |
Connections |
|
|
Other |
|
|
| Parts Warranty |
2 Years |
2 Years |
| Labor Warranty |
2 Years |
2 Years |