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KEF KUBE 8b vs KEF KUBE 12b Comparison
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KEF KUBE 8b

Powered Subwoofer | 34-140 Hz

KEF KUBE 8b
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KEF KUBE 12b

Powered Subwoofer | 22-140 Hz

KEF KUBE 12b
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KEF KUBE 8b KEF KUBE 8b
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KEF KUBE 12b KEF KUBE 12b
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KEF KUBE 8b
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KEF KUBE 12b
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KEF KUBE 8b vs KEF KUBE 12b Speaker Comparison

In this review, we will be comparing KUBE 8b and KUBE 12b, two Powered Subwoofer speakers by 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 KEF KUBE 8b and KEF KUBE 12b first before getting into our more detailed comparison.

KEF KUBE 8b Key Specs

  • 8" Not given Woofer
  • 34-140 Hz Frequency Response
  • 300 watts Max Amplifier Output
  • Weight:11.36kg
  • Dimensions (H x W x D): 294.0" x 11-5/8" x 13-5/16"( 294.0 x 296.0 x 339.0mm )

KEF KUBE 12b Key Specs

  • 12" Not given Woofer
  • 22-140 Hz Frequency Response
  • 300 watts Max Amplifier Output
  • Weight:20.68kg
  • Dimensions (H x W x D): 410.0" x 15-9/16" x 17-3/8"( 410.0 x 396.0 x 442.0mm )

KUBE 8b and KUBE 12b are members of KEF's KUBE series of subwoofers. Below you can find other subs from this series.

KEF KUBE Series Subwoofers History
Model Frequency Woofer Amp Power
KEF KUBE 8b
34-140k Hz 8" 300 watts
KEF KUBE 10b
  
24-140k Hz 10" 300 watts
KEF KUBE 12b
22-140k Hz 12" 300 watts

In the following sections, we will get into details in order to better understand how the KEF KUBE 8b and KEF KUBE 12b 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.Both KEF KUBE 8band KEF KUBE 12b have a single woofer setup however the KEF KUBE 8b's woofer is 8-inch whereas the KEF KUBE 12b features a 12-inch woofer.

Frequency Response

KUBE 8b has a frequency range of 34-140 Hz whereas KUBE 12b has a frequency range of 22-140 Hz. With a minimum frequency of 22Hz, the KUBE 12b 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

KEF KUBE 8b
KEF KUBE 12b
Min
Average
Max
High Frequency

Subwoofer Speakers

KEF KUBE 8b
KEF KUBE 12b
Min
Average
Max

Cabinet Type

Both KEF KUBE 8b and KEF KUBE 12b have Acoustic Suspension type cabinets. 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 KEF KUBE 8b's and KEF KUBE 12b's external dimensions. 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) whereas KEF KUBE 12b has external dimensions of 410.0 x 396.0 x 442.0mm ( 16-1/8 x 15-9/16 x 17-3/8inch) .

KEF KUBE 12b is clearly the larger of the two speakers. Its body is 100mm wider, 116mm taller and 103mm deeper than KEF KUBE 8b.

Below you can see the front view size comparison of KEF KUBE 8b and KEF KUBE 12b in scale.

KEF KUBE 8b vs KEF KUBE 12b Size Comparison - Front View
Comparison image of KEF KUBE 8b and KEF KUBE 12b 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 KEF KUBE 8b is approximately 1003.4cm2 / 155.5inch2 and base area of the KEF KUBE 12b is approximately 1750.3cm2 / 271.3inch2. The KUBE 8b requires 43% less surface area than the KUBE 12b which gives it a small advantage 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 KEF KUBE 8b weighs 11.36kg / 25lbs and the KEF KUBE 12b weighs 20.68kg / 45.5lbs. This makes the KUBE 12b 82% heavier than the KUBE 8b.

Here is a comparison of how KUBE 8b and KUBE 12b's weights compare with the average, max and min weights in Powered Subwoofer class.

Weight
All Subwoofer Speakers
KEF KUBE 8b
KEF KUBE 12b
Min
Average
Max

What's in the Box of KEF KUBE 8b?

Here are the items that are included inside the box of KUBE 8b:
  • Powered subwoofer
  • 6.5-feet AC power cord
  • Speaker-level input block
  • User Manual
  • Important Safety Information
  • Warranty Information
  • What's in the Box of KEF KUBE 12b?

    Here are the items that come with the KUBE 12b:
  • Powered subwoofer
  • 6.5-feet AC power cord
  • Speaker-level input block
  • User Manual
  • Important Safety Information
  • Warranty Information

  • Reasons to choose KEF KUBE 8b over KEF KUBE 12b
    Height 294mm vs 410mm Easier to fit in smaller spaces
    Base Surface Area 1003cm2 vs 1750cm2 Takes less floor space
    Price per pair* 600USD vs 900USD costs less (*prices may change depending on the seller, location and time)
    Reasons to choose KEF KUBE 12b over KEF KUBE 8b
    Woofer Size 12 inches vs 8 inches Larger woofer
    Low Frequency Response 22 Hz vs 34 Hz Generates deeper bass
    Wireless Operation Optional vs No Connect your subwoofer to your system wireless
    KEF KUBE 8b vs KEF KUBE 12b Specs Table
    Detailed comparison of specifications
    General KEF KUBE 8b KEF KUBE 12b
    Brand KEF KEF
    Speaker Type Powered Subwoofer Powered Subwoofer
    Max Amplifier Output 300 watts 300 watts
    Frequency Response 34-140 Hz 22-140 Hz
    Amplifier
    Watts RMS (Continuous) 300-watt RMS 300-watt RMS
    Drivers
    Woofer Quantity 1 1
    Woofer Size 8" 12"
    Woofer Composition Not given Not given
    Tweeter Size - -
    Aimable Tweeter No No
    Midrange Driver No No
    Crossover Frequency 40-140 Hz 40-140 Hz
    Firing Direction front front
    Physical Specs
    Height 294.0mm (11.6") 410.0mm (16.1")
    Width 296.0mm (11.7") 396.0mm (15.6")
    Depth 339.0mm (13.3") 442.0mm (17.4")
    Weight 11.36kg (25lbs) 20.68kg (45.5lbs)
    Enclosure Acoustic Suspension Acoustic Suspension
    Moisture Resistancy No No
    Connections
    Other
    Parts Warranty 2 Years 2 Years
    Labor Warranty 2 Years 2 Years

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