KEF Kube 8b (Black) Subwoofer

KEF Kube 8b (Black)

Subwoofer

Out of stock
£499
Deep bass from a compact cabinet – the KEF Kube 8b is a room-friendly subwoofer.

iBX for powerful bass you can feel

KEF’s Kube subwoofers feature iBX (Intelligent Bass Extension) for the deepest bass from the most compact cabinets. The iBX algorithm creates an extended depth of bass that easily exceeds expectations for this size of sub. Backing this up is a powerful 300 watts, Class-D amplifier. This is enough to power the high quality 8" bass unit to high levels and low frequencies. With effortless bass on tap, the Kube 8b is ideal for both movies and music.

Power, controlled
Despite its high power rating, the KEF Kube is about more than just firepower. The sealed cabinet not only offers high levels of rigidity but also gives a tight, controlled bass that's never overblown or sloppy. A 3-position DSP (EQ) control allows adjustment of the Kube's response to compensate for different room acoustics and personal preference. There's also a phase switch. This lets you reverse the phase, giving perfectly timed bass whether the sub is in front or behind you.

Effortlessly stylish
Most subs deserve to be hidden away, but not the Kef Kube! Featuring smooth lines, a wrap-around grille and gloss black top panel, the Kube 8b is one subwoofer you’ll be happy to have on display. Being the smallest in the range, the Kube 8b is also easy top to fit in tight spaces and ideal for smaller rooms.

Compact yet powerful, the KEF Kube 8b offers a punchy sound without the bulk.

6 Year Supercare Guarantee
£49.85

Add our Supercare Guarantee to your basket when you check out. We'll cover your items for 6 years and give you your money back if unused.

Lowest price guaranteed!

We’ll beat any genuine advertised price, even from the web & give you up to £100!

We're confident that our prices are amongst the very keenest out there, so we've made it as easy as pie to qualify for our Price Beat. Richer Sounds also guarantees to beat web prices, and Price Beat is even valid for 7 days after purchase, so if you've seen a cheaper price, let us know, and we'll happily beat that price by up to £100!

Products must be brand new, boxed, carry a comparable guarantee and be in stock at time of purchase. Richer Sounds price used to compare will be net of any voucher / trade in discounts.
T&Cs apply

Buy now, pay later available
by phone, on items over £500

We offer 6 month interest free options. Call our Telesales team for details.

For purchases over £500, pay a 10% deposit now and the balance in 6 months. Pay the balance in full before the end of the 6 months and there is no interest to pay whatsoever, just a one-off settlement fee of £29. Subject to application, financial circumstances and borrowing history. Ts&Cs apply. 19.9% APR representative. Find out more

 Disabled assistance

All products that are available to purchase on the Richer Sounds website can be delivered free to blind, partially sighted or those with a disability.

Please contact web after sales for more info.
For delivery of in-store only deals, please contact your local store for more details.
T&Cs apply - see our delivery page.
Deep bass from a compact cabinet – the KEF Kube 8b is a room-friendly subwoofer.

iBX for powerful bass you can feel

KEF’s Kube subwoofers feature iBX (Intelligent Bass Extension) for the deepest bass from the most compact cabinets. The iBX algorithm creates an extended depth of bass that easily exceeds expectations for this size of sub. Backing this up is a powerful 300 watts, Class-D amplifier. This is enough to power the high quality 8" bass unit to high levels and low frequencies. With effortless bass on tap, the Kube 8b is ideal for both movies and music.

Power, controlled
Despite its high power rating, the KEF Kube is about more than just firepower. The sealed cabinet not only offers high levels of rigidity but also gives a tight, controlled bass that's never overblown or sloppy. A 3-position DSP (EQ) control allows adjustment of the Kube's response to compensate for different room acoustics and personal preference. There's also a phase switch. This lets you reverse the phase, giving perfectly timed bass whether the sub is in front or behind you.

Effortlessly stylish
Most subs deserve to be hidden away, but not the Kef Kube! Featuring smooth lines, a wrap-around grille and gloss black top panel, the Kube 8b is one subwoofer you’ll be happy to have on display. Being the smallest in the range, the Kube 8b is also easy top to fit in tight spaces and ideal for smaller rooms.

Compact yet powerful, the KEF Kube 8b offers a punchy sound without the bulk.
Brand KEF
Colour Black
Infinite baffle (sealed) Yes
Auto On/Off Yes
Weight (KG) 11.3
Included Cables No
Power Rating (Watts) 300
Speaker Dimensions WxDxH (mm) 310 x 293 x 293mm
Driver Units 8 inch driver
Crossover Frequency (Hz) 40 - 140
Dimensions WxDxH (mm) 293 x 310 x 293
Freq Response (Hz) 34 - 140
Rated 4 out of 5 by from Good replacement I bought this when my old Kef sub gave up, and it's a fine updated product
Date published: 2020-03-09
Rated 5 out of 5 by from Perfect fit I bought the KEF sub a couple of weeks ago and am delighted not only with it's performance in enhancing the low end sound of my system, but also how unibtrusive it us both physically and soundwise. Whilst filling in the extreme low end which my KEF Q350s cannot quite reach, the bass is smooth and consistent.
Date published: 2018-07-09
Rated 5 out of 5 by from great sound from such a small sub i wanted the 10b but settled for the 8 glad I did kicks out all the base I want!
Date published: 2018-04-23
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£499
KEF Kube 8b (Black) is rated 4.7 out of 5 by 3.
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Please call your local store Members of our team are happily working from home to provide advice, info on stock and other help. They can also process sales and arrange delivery direct from our warehouse. Buy by phone Call our national Telesales team on
0333 900 0093

6 Year Supercare Guarantee
£49.85

Add our Supercare Guarantee to your basket when you check out. We'll cover your items for 6 years and give you your money back if unused.

6 YEAR SUPERCARE GUARANTEE COSTS JUST £9.99 ON ALL ITEMS UNDER £100, OR 10% OF PURCHASE PRICE ON ANYTHING OVER £100.

We think you’ll agree that our Supercare guarantee offers fantastic value. What’s more, if you don’t use our it in the 6 year period, we’ll refund the cost of it. You really can’t say fairer than that!
Plus, if we can’t fix a fault, we will give you a like-for-like replacement.
Find out full details here.

Lowest price guaranteed!

We’ll beat any genuine advertised price, even from the web & give you up to £100!

We're confident that our prices are amongst the very keenest out there, so we've made it as easy as pie to qualify for our Price Beat. Richer Sounds also guarantees to beat web prices, and Price Beat is even valid for 7 days after purchase, so if you've seen a cheaper price, let us know, and we'll happily beat that price by up to £100!

Products must be brand new, boxed, carry a comparable guarantee and be in stock at time of purchase. Richer Sounds price used to compare will be net of any voucher / trade in discounts.
T&Cs apply

Buy now, pay later available
by phone, on items over £500

We offer 6 month interest free options. Call our Telesales team for details.

For purchases over £500, pay a 10% deposit now and the balance in 6 months. Pay the balance in full before the end of the 6 months and there is no interest to pay whatsoever, just a one-off settlement fee of £29. Subject to application, financial circumstances and borrowing history. Ts&Cs apply. 19.9% APR representative. Find out more

 Disabled assistance

All products that are available to purchase on the Richer Sounds website can be delivered free to blind, partially sighted or those with a disability.

Please contact web after sales for more info.
For delivery of in-store only deals, please contact your local store for more details.
T&Cs apply - see our delivery page.