Short answer: the Sigberg Audio SBS Gen 2 for better sound quality, the KEF LSX II LT for the lower price. The Sigberg Audio SBS Gen 2 ranks #24 of 64 powered bookshelf speakers at $18043.20. The KEF LSX II LT ranks #27 at $469.99, $17573.21 cheaper.
What the KEF LSX II LT offers: Coaxial (Uni-Q-style) driver keeps the tweeter centered in the midrange, giving wide and consistent dispersion both horizontally and vertically (about ±60° each) - a wide sweet spot for multiple seats or positions. The KEF Connect app provides genuinely useful DSP control: desk/wall boundary compensation, adjustable bass contour (standard/less/extra), treble trim, and subwoofer integration, letting you tune the sound to wherever it’s placed. Distortion at a moderate 86dB looks good for the speaker’s compact size. Tonal profile stays consistent from 0° to 30° off-axis, so side-seat listeners hear essentially the same balance as someone centered. Extensive connectivity for its size: HDMI, USB, optical, sub output, plus Wi-Fi/Bluetooth. Clearly outperformed the reviewer’s soundbars, including ones bundled with their own subwoofers, as a TV audio replacement. Watch for: Small drivers mean it’s SPL-limited: bass compression kicks in around 88-92dB/1m per speaker, and multitone distortion crosses the reviewer’s 3% threshold around 96dB - not intended for loud or large-room duty. F3 of 55Hz and F10 of 46Hz mean it loses much of its bass by around 50Hz; a subwoofer (controllable through the same app) is needed for real low end. Diffraction dips appear around 4-5kHz and again near 8kHz, likely tied to the tweeter housing or surround, giving a mild reduction in treble attack and sibilance. A possible port or enclosure resonance shows up around 800Hz in the rear-radiation measurements, though the reviewer wasn’t certain of the exact cause or whether it’s audible. No analog input on this LT variant, so a turntable can’t be connected directly - only the pricier standard LSX II model includes one.
What the Sigberg Audio SBS Gen 2 offers: The best-measuring of Sigberg’s three active systems, with a 6.74 Spinorama preference score with a perfect subwoofer versus 6.26 for the SBS.1 and 5.91 for the Manta. This is the appropriate apples-to-apples comparison because all three are designed for use with companion subwoofers. Unlike the other two measurements, the SBS Gen 2 data includes its subwoofer and verifies 24Hz bass extension. Its updated asymmetric 1st/3rd-order linear-phase crossover also delivers the best on-axis linearity and in-room and sound-power smoothness of the three. Active 3-channel Hypex nCore Class D amplification (350W per speaker) includes a 9-band parametric EQ. Watch for: Slightly wider directivity variation than the Manta (spinorama directivity index standard deviation 3.27 versus 2.50), though broadly comparable to the SBS.1’s 3.19. Sold only as a complete speaker-and-subwoofer system with pricing well into flagship territory. Built to order with a lead time of several months.
Buy the KEF LSX II LT if the price matters more than sound quality. Buy the Sigberg Audio SBS Gen 2 if sound quality matters more than the price.
Specifications Side By Side
| KEF LSX II LT | Sigberg Audio SBS Gen 2 | |
|---|---|---|
| Price | $469.99 | $18,043.20 for the full system (2 speakers + 2 dedicated subwoofers, built to order) |
| Ranked | #27 of 64 in Medium Size Powered Bookshelf Speakers | #24 of 64 in Medium Size Powered Bookshelf Speakers |
| Dimensions | 9.5"H x 6.1"W x 7.1"D (241.3 x 154.9 x 180.3 mm) | 16.1"H x 7.5"W x 9.1"D (410 x 190 x 230 mm) |
| Inputs | Wifi, USB-C, HDMI, Optical, Bluetooth | XLR, RCA, Optical, Coaxial/SPDIF, AES |
| Outputs | RCA Subwoofer | - |
| Drivers | 115mm (4.5in.) magnesium/aluminium alloy cone woofer, 19mm (0.75in.) aluminium dome tweeter | 5.5" midbass, 5.5" coaxial mid/tweeter with 1" silk dome |
| Weight | 15 lbs / 6.8 kg | 20.9 lbs / 9.5 kg each |
| App | No | No |
| Bluetooth | No | No |
| EQ | No | Yes (9-band parametric, factory presets) |
| Output Power | 100w RMS Per Speaker | 350W per speaker |
| Bass Extension (-3dB) | 55Hz (measured, Erin’s Audio Corner) | 24Hz (measured, spinorama.org, with companion subwoofer) |
| Bass Extension (-10dB) | 46Hz (measured, Erin’s Audio Corner) | - |
| Sensitivity | 84dB (measured at 0.3V/1m, Erin’s Audio Corner) | - |
| Enclosure | - | sealed |
| Max SPL | - | 116dB |
| DSP | - | Yes |
| Country | - | Norway |
| Measurement Source | - | Manufacturer |
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- Edifier S2000MKIII vs Reflector Audio Square Two
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- Kali LP-UNF vs Sigberg Audio SBS Gen 2
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Prices on this page were last checked August 25, 2026 at 6:19 AM 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.
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The Two Speakers In Full
KEF LSX II LT: $469.99 Amazon eBay
Pros: Coaxial (Uni-Q-style) driver keeps the tweeter centered in the midrange, giving wide and consistent dispersion both horizontally and vertically (about ±60° each) - a wide sweet spot for multiple seats or positions. The KEF Connect app provides genuinely useful DSP control: desk/wall boundary compensation, adjustable bass contour (standard/less/extra), treble trim, and subwoofer integration, letting you tune the sound to wherever it’s placed. Distortion at a moderate 86dB looks good for the speaker’s compact size. Tonal profile stays consistent from 0° to 30° off-axis, so side-seat listeners hear essentially the same balance as someone centered. Extensive connectivity for its size: HDMI, USB, optical, sub output, plus Wi-Fi/Bluetooth. Clearly outperformed the reviewer’s soundbars, including ones bundled with their own subwoofers, as a TV audio replacement.
Cons: Small drivers mean it’s SPL-limited: bass compression kicks in around 88-92dB/1m per speaker, and multitone distortion crosses the reviewer’s 3% threshold around 96dB - not intended for loud or large-room duty. F3 of 55Hz and F10 of 46Hz mean it loses much of its bass by around 50Hz; a subwoofer (controllable through the same app) is needed for real low end. Diffraction dips appear around 4-5kHz and again near 8kHz, likely tied to the tweeter housing or surround, giving a mild reduction in treble attack and sibilance. A possible port or enclosure resonance shows up around 800Hz in the rear-radiation measurements, though the reviewer wasn’t certain of the exact cause or whether it’s audible. No analog input on this LT variant, so a turntable can’t be connected directly - only the pricier standard LSX II model includes one.
Full KEF LSX II LT review and specifications →
| App | No |
|---|---|
| Bass Extension (-10dB) | 46Hz (measured, Erin's Audio Corner) |
| Bass Extension (-3dB) | 55Hz (measured, Erin's Audio Corner) |
| Bluetooth | No |
| Dimensions | 9.5"H x 6.1"W x 7.1"D (241.3 x 154.9 x 180.3 mm) |
| Drivers | 115mm (4.5in.) magnesium/aluminium alloy cone woofer, 19mm (0.75in.) aluminium dome tweeter |
| EQ | No |
| Inputs | Wifi, USB-C, HDMI, Optical, Bluetooth |
| Output Power | 100w RMS Per Speaker |
| Outputs | RCA Subwoofer |
| Sensitivity | 84dB (measured at 0.3V/1m, Erin's Audio Corner) |
| Weight | 15 lbs / 6.8 kg |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
Sigberg Audio SBS Gen 2: $18,043.20 for the full system (2 speakers + 2 dedicated subwoofers, built to order) Sigberg Audio eBay
Pros: The best-measuring of Sigberg’s three active systems, with a 6.74 Spinorama preference score with a perfect subwoofer versus 6.26 for the SBS.1 and 5.91 for the Manta. This is the appropriate apples-to-apples comparison because all three are designed for use with companion subwoofers. Unlike the other two measurements, the SBS Gen 2 data includes its subwoofer and verifies 24Hz bass extension. Its updated asymmetric 1st/3rd-order linear-phase crossover also delivers the best on-axis linearity and in-room and sound-power smoothness of the three. Active 3-channel Hypex nCore Class D amplification (350W per speaker) includes a 9-band parametric EQ.
Cons: Slightly wider directivity variation than the Manta (spinorama directivity index standard deviation 3.27 versus 2.50), though broadly comparable to the SBS.1’s 3.19. Sold only as a complete speaker-and-subwoofer system with pricing well into flagship territory. Built to order with a lead time of several months.
Full Sigberg Audio SBS Gen 2 review and specifications →
| App | No |
|---|---|
| Bass Extension (-3dB) | 24Hz (measured, spinorama.org, with companion subwoofer) |
| Bluetooth | No |
| Country | Norway |
| DSP | Yes |
| Dimensions | 16.1"H x 7.5"W x 9.1"D (410 x 190 x 230 mm) |
| Drivers | 5.5" midbass, 5.5" coaxial mid/tweeter with 1" silk dome |
| EQ | Yes (9-band parametric, factory presets) |
| Enclosure | sealed |
| Inputs | XLR, RCA, Optical, Coaxial/SPDIF, AES |
| Max SPL | 116dB |
| Measurement Source | Manufacturer |
| Output Power | 350W per speaker |
| Weight | 20.9 lbs / 9.5 kg each |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
- Sigberg Audio SBS Gen 2 vs IK Multimedia iLoud MTM MKII
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- Sigberg Audio SBS Gen 2 vs Kali Audio IN-5
- Sigberg Audio SBS Gen 2 vs Yamaha HS5
- Sigberg Audio SBS Gen 2 vs Edifier R1280DB
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