Short answer: the Q Acoustics Q SUB120. Both are rated 3.8/5 for sound quality (#79 and #78 of 212 subwoofers), and the Q Acoustics Q SUB120 costs $1,399 against $1,499.99 for the KEF Kube 15 MIE, so with nothing between them on sound quality, price settles it.
Why pick the KEF Kube 15 MIE: Largest member of the Kube MIE series, housing a 15-inch front-firing driver in a sealed cabinet powered by 300W Class-D amplification. The tradeoff: Weighs 60.6 lbs (27.5 kg) with dimensions over 500mm on each side, making it a substantial presence in a room, and requires dedicated placement without easy concealment.
What the Q Acoustics Q SUB120 does well: Sealed 12 inch subwoofer with a 300W continuous (600W peak) amplifier, up from the 220W of the Q Acoustics Q B12 it replaces. The catch: No independent measurements yet, so its output can’t be compared with ranked subwoofers; the rating is estimated from the measured Q Acoustics Q B12, which reached 115.2dB in the 40 to 80Hz CEA-2010 bands but only 98.4dB at 20Hz.
Buy the Q Acoustics Q SUB120. Both are rated the same for sound quality, and it costs $100.99 less than the KEF Kube 15 MIE.
About the ratings: neither speaker has been measured yet, so both ratings are estimated from measured siblings and predecessors (likely ranges: KEF Kube 15 MIE 3.6 to 4.0; Q Acoustics Q SUB120 3.5 to 4.1). Treat this verdict as provisional.
Want more options? Browse the full Subwoofers rankings.
Specifications Side By Side
| KEF Kube 15 MIE | Q Acoustics Q SUB120 | |
|---|---|---|
| Price | $1,499.99 | $1,399.00 |
| Ranked | #78 of 212 in Medium Home Subwoofers (30-75 lbs) Estimated | #79 of 212 in Medium Home Subwoofers (30-75 lbs) Estimated |
| Warranty | 5/2 | - |
| Enclosure | sealed | sealed |
| Drivers | 15” driver | 12” (305mm) driver |
| Amplifier Power | 300W | 300W RMS (600W peak) |
| Frequency Response | 20Hz - 140Hz (±3dB) (manufacturer specified) | 28-250Hz (-6dB, manufacturer specified) |
| Maximum SPL | 116 dB | 114dB @ 1m (manufacturer specified) |
| Dimensions | 20.4”H x 19.7”W x 20.3”D (519 x 500 x 515 mm) | 17”H x 15.7”W x 15.7”D (432 x 400 x 400 mm) |
| Weight | 60.6 lbs (27.5 kg) | 49.6 lbs (22.5 kg) |
| Cabinet Color | black | black, white |
| Country | United Kingdom | United Kingdom |
| Crossover Frequency | - | 40-250Hz (adjustable low pass) |
Related Speaker Comparisons
How KEF Kube 15 MIE compares with other leading options:
- REL Acoustics T/9x vs KEF Kube 15 MIE
- ELAC Varro RS700 vs KEF Kube 15 MIE
- ELAC Varro RS700 vs Q Acoustics Q SUB120
- Q Acoustics Q SUB120 vs ELAC Varro RS500
- Klipsch Flexus Sub 200 vs Klipsch SPL-100
Prices on this page were last checked October 11, 2026 at 4:59 PM UTC. Product prices and availability are accurate as of that date/time and are subject to change; the price and availability shown on Amazon at the time of purchase will apply to the purchase of this product.
As an eBay Partner, we may be compensated if you make a purchase.
The Two Speakers In Full
KEF Kube 15 MIE: $1,499.99 Estimated Amazon KEF eBay
Same family: the KEF Kube 8 MIE (smaller subwoofer, estimated 3.6/5), the KEF Kube 10 MIE (smaller subwoofer, estimated 3.7/5) and the KEF Kube 12 MIE (smaller subwoofer, ranked lower, estimated 3.7/5). See every KEF Kube generation.
Pros: Largest member of the Kube MIE series, housing a 15-inch front-firing driver in a sealed cabinet powered by 300W Class-D amplification. Delivers 20Hz to 140Hz (±3dB) extension and 116dB max SPL with Music Integrity Engine DSP processing and multiple room placement presets.
Cons: Weighs 27.5 kg with dimensions over 500mm on each side, making it a substantial presence in a room, and requires dedicated placement without easy concealment.
Full KEF Kube 15 MIE review and specifications →
| Released | Feb 2024 (2 years ago) |
|---|---|
| Amplifier Power | 300W |
| Cabinet Color | black |
| Country | United Kingdom |
| Dimensions | 20.4”H x 19.7”W x 20.3”D (519 x 500 x 515 mm) |
| Drivers | 15” driver |
| Enclosure | sealed |
| Frequency Response | 20Hz - 140Hz (±3dB) (manufacturer specified) |
| Maximum SPL | 116 dB |
| Warranty | 5/2 |
| Weight | 60.6 lbs (27.5 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- No independent measurement review is linked for this model; it is ranked from hands-on listening and comparison against similarly priced speakers.
- Head-to-Head Comparisons
Q Acoustics Q SUB120: $1,399.00 Estimated Amazon Q Acoustics eBay
Older model: the Q Acoustics Q B12 (ranked higher, rated 3.8/5). See every Q Acoustics Subwoofers generation.
Pros: Sealed 12 inch subwoofer with a 300W continuous (600W peak) amplifier, up from the 220W of the Q Acoustics Q B12 it replaces. Onboard DSP adds automatic input detection, dual phase and delay controls, and a 40 to 250Hz low pass crossover for easier room integration. Q Acoustics rates it at 114dB maximum output and 28Hz at the -6dB point.
Cons: No independent measurements yet, so its output can’t be compared with ranked subwoofers; the rating is estimated from the measured Q Acoustics Q B12, which reached 115.2dB in the 40 to 80Hz CEA-2010 bands but only 98.4dB at 20Hz. As a sealed design it gives up some deep bass output to similarly priced ported subwoofers. At 22.5 kg it is heavy for its size.
Full Q Acoustics Q SUB120 review and specifications →
| Released | Mar 2025 (1 year ago) |
|---|---|
| Amplifier Power | 300W RMS (600W peak) |
| Cabinet Color | black, white |
| Country | United Kingdom |
| Crossover Frequency | 40-250Hz (adjustable low pass) |
| Dimensions | 17”H x 15.7”W x 15.7”D (432 x 400 x 400 mm) |
| Drivers | 12” (305mm) driver |
| Enclosure | sealed |
| Frequency Response | 28-250Hz (-6dB, manufacturer specified) |
| Maximum SPL | 114dB @ 1m (manufacturer specified) |
| Weight | 49.6 lbs (22.5 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- No independent measurement review is linked for this model; it is ranked from hands-on listening and comparison against similarly priced speakers.
- Head-to-Head Comparisons