Short answer: the Devialet Phantom II 98 dB. It ranks #9 of 65 powered bookshelf speakers by sound quality at $2998; the KEF LS50 Wireless II ranks #14 and costs $2999, which makes this an easy call rather than a real tradeoff.
What the KEF LS50 Wireless II offers: Erin’s measurements give preference scores of 4.52 standalone and 6.59 with an ideal subwoofer, with a -3dB point around 51Hz. The coincident Uni-Q layout helps preserve tonal consistency across horizontal and vertical listening positions. Low listening-window narrow-band deviation of 0.308 supports relatively clean midrange reproduction. HDMI eARC and streaming functions make it a capable all-in-one stereo system. Watch for: The 3.0dB response span is good but not reference-leading, and dispersion still varies with frequency. Compact bass drivers limit deep-bass output. App placement adjustments are not the same as microphone-based automatic room correction. The price and primary/secondary architecture are practical trade-offs; neither driver geometry nor a single directivity statistic guarantees the best sound in every room.
What the Devialet Phantom II 98 dB offers: The manufacturer-supplied measurement shows unusually deep bass for the enclosure size: -3dB at 30Hz. Scores of 6.07 standalone and 7.15 with an ideal subwoofer suggest that its appeal is not limited to bass quantity. Integrated amplification and network playback can replace several components, and its 2.3dB midrange response span is reasonably even. Watch for: Small-enclosure bass extension at the measurement level does not guarantee the same response at high volume. Stereo requires two units, and the integrated architecture offers less system flexibility than conventional monitors.
Buy the Devialet Phantom II 98 dB. It ranks higher for sound quality than the KEF LS50 Wireless II and costs less, so there is no real case for the other one.
Looking for alternatives? See the complete Powered Home rankings.
Specifications Side By Side
| KEF LS50 Wireless II | Devialet Phantom II 98 dB | |
|---|---|---|
| Price | $2,999.00 per pair | $2,998 per pair |
| Ranked | #14 of 65 in Medium Size Powered Bookshelf Speakers | #9 of 65 in Medium Size Powered Bookshelf Speakers |
| Bass Extension (-10dB) | 41.5Hz (measured, spinorama.org) | approximately 22.6Hz (measured, spinorama.org) |
| Bass Extension (-3dB) | 51.3Hz (measured, spinorama.org) | 30Hz (measured, spinorama.org) |
| Inputs | HDMI eARC, optical, digital coaxial, 3.5mm analog, USB-A (service), Ethernet | Wi-Fi, Ethernet, Bluetooth, AirPlay 2, Spotify Connect, UPnP, Roon Ready, analog/optical combo jack |
| Drivers | Uni-Q coincident array: 130mm aluminum woofer + 25mm MAT aluminum dome tweeter | One aluminum full-range driver; two aluminum bass drivers |
| App | KEF Connect (placement EQ presets, source selection, firmware updates) | - |
| Bluetooth | Yes, 4.2 | - |
| EQ | Yes, fixed placement presets (desk/bookshelf/wall-mount) - no automatic room correction | - |
| Weight | 44.3 lbs (20.1 kg) for the pair | 9.5 lbs (4.3 kg) each |
| Amplifier Power | 280W (LF) + 100W (HF) per speaker, bi-amped | 400W RMS each |
| Dimensions | 12" x 7.9" x 12.2" (305 x 200 x 311 mm) each | 6.6 x 6.2 x 8.6 in each |
| Frequency Response | 45Hz - 28kHz ±3dB | - |
| Maximum SPL | 108dB at 1m (manufacturer specified) | 98dB at 1m each (manufacturer specified) |
| Spinorama Preference Score | 4.52 | 6.07 |
| Spinorama Preference Score with Perfect Sub | 6.59 | 7.15 |
| Subwoofer Output | Yes | - |
| Outputs | RCA subwoofer | - |
| Bluetooth Codecs | - | SBC, AAC |
Related Speaker Comparisons
How Devialet Phantom II 98 dB compares with other leading options:
- Genelec 8331A vs Devialet Phantom II 98 dB
- Neumann KH120 MKII vs Devialet Phantom II 98 dB
- Genelec 8030C vs Devialet Phantom II 98 dB
- Neumann KH80 DSP vs Devialet Phantom II 98 dB
- Devialet Phantom II 98 dB vs Dynaudio LYD 5
Prices on this page were last checked September 16, 2026 at 12:41 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 LS50 Wireless II: $2,999.00 per pair Amazon KEF Crutchfield eBay
Pros: Erin’s measurements give preference scores of 4.52 standalone and 6.59 with an ideal subwoofer, with a -3dB point around 51Hz. The coincident Uni-Q layout helps preserve tonal consistency across horizontal and vertical listening positions. Low listening-window narrow-band deviation of 0.308 supports relatively clean midrange reproduction. HDMI eARC and streaming functions make it a capable all-in-one stereo system. Measured bass extension of 51.3Hz (-3dB).
Cons: The 3.0dB response span is good but not reference-leading, and dispersion still varies with frequency. Compact bass drivers limit deep-bass output. App placement adjustments are not the same as microphone-based automatic room correction. The price and primary/secondary architecture are practical trade-offs; neither driver geometry nor a single directivity statistic guarantees the best sound in every room.
Full KEF LS50 Wireless II review and specifications →
| Amplifier Power | 280W (LF) + 100W (HF) per speaker, bi-amped |
|---|---|
| App | KEF Connect (placement EQ presets, source selection, firmware updates) |
| Bass Extension (-10dB) | 41.5Hz (measured, spinorama.org) |
| Bass Extension (-3dB) | 51.3Hz (measured, spinorama.org) |
| Bluetooth | Yes, 4.2 |
| Dimensions | 12" x 7.9" x 12.2" (305 x 200 x 311 mm) each |
| Drivers | Uni-Q coincident array: 130mm aluminum woofer + 25mm MAT aluminum dome tweeter |
| EQ | Yes, fixed placement presets (desk/bookshelf/wall-mount) - no automatic room correction |
| Frequency Response | 45Hz - 28kHz ±3dB |
| Inputs | HDMI eARC, optical, digital coaxial, 3.5mm analog, USB-A (service), Ethernet |
| Maximum SPL | 108dB at 1m (manufacturer specified) |
| Outputs | RCA subwoofer |
| Spinorama Preference Score | 4.52 |
| Spinorama Preference Score with Perfect Sub | 6.59 |
| Subwoofer Output | Yes |
| Weight | 44.3 lbs (20.1 kg) for the pair |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
- KEF LS50 Wireless II vs JBL 305P MKII
- KEF LS50 Wireless II vs Vanatoo Transparent One Encore Plus
- KEF LS50 Wireless II vs IK Multimedia iLoud MTM MKII
- KEF LS50 Wireless II vs Klipsch The Fives
- KEF LS50 Wireless II vs Genelec 8020D
- KEF LS50 Wireless II vs Kali Audio SM-5
- KEF LS50 Wireless II vs Kali Audio IN-5
- KEF LS50 Wireless II vs Genelec 8320A
- See all 43 comparisons
Devialet Phantom II 98 dB: $2,998 per pair Devialet eBay
Pros: The manufacturer-supplied measurement shows unusually deep bass for the enclosure size: -3dB at 30Hz. Scores of 6.07 standalone and 7.15 with an ideal subwoofer suggest that its appeal is not limited to bass quantity. Integrated amplification and network playback can replace several components, and its 2.3dB midrange response span is reasonably even. Measured bass extension of 30Hz (-3dB).
Cons: Small-enclosure bass extension at the measurement level does not guarantee the same response at high volume. Stereo requires two units, and the integrated architecture offers less system flexibility than conventional monitors.
Full Devialet Phantom II 98 dB review and specifications →
| Amplifier Power | 400W RMS each |
|---|---|
| Bass Extension (-10dB) | approximately 22.6Hz (measured, spinorama.org) |
| Bass Extension (-3dB) | 30Hz (measured, spinorama.org) |
| Bluetooth Codecs | SBC, AAC |
| Dimensions | 6.6 x 6.2 x 8.6 in each |
| Drivers | One aluminum full-range driver; two aluminum bass drivers |
| Inputs | Wi-Fi, Ethernet, Bluetooth, AirPlay 2, Spotify Connect, UPnP, Roon Ready, analog/optical combo jack |
| Maximum SPL | 98dB at 1m each (manufacturer specified) |
| Spinorama Preference Score | 6.07 |
| Spinorama Preference Score with Perfect Sub | 7.15 |
| Weight | 9.5 lbs (4.3 kg) each |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
- Devialet Phantom II 98 dB vs Genelec 8020D
- Devialet Phantom II 98 dB vs Genelec 8330A
- Devialet Phantom II 98 dB vs Klipsch The Fives
- Devialet Phantom II 98 dB vs Dynaudio LYD 5
- Devialet Phantom II 98 dB vs JBL 305P MKII
- Devialet Phantom II 98 dB vs Neumann KH80 DSP
- Devialet Phantom II 98 dB vs Genelec 8030C
- Devialet Phantom II 98 dB vs Vanatoo Transparent One Encore Plus
- See all 37 comparisons