Short answer: the Monolith THX-365IW. It ranks #8 of 28 in-wall speakers by sound quality, rated 4.0/5, at $999.98; the KEF CI200RR-THX ranks #12, rated 3.7/5, and costs $2,399.98, which makes this an easy call rather than a real tradeoff.
The Monolith THX-365IW is the deeper-bass choice. An affordable three way in-wall speaker with accurate sound, deep bass for its type and a long warranty. Its bass reaches about 54.6Hz before falling 3dB, against 82.5Hz for the KEF CI200RR-THX. The catch: ASR’s first measurement of this speaker scored far lower (preference score 1.33, or 5.10 with a subwoofer, with -3dB at 108Hz), so results depend heavily on how it is installed and enclosed.
The case for the KEF CI200RR-THX: An in-ceiling speaker with an 8 inch woofer and coaxial tweeter, big enough to move real air in a family room. The catch: Spinorama’s measurement of this model is a lower-confidence manufacturer curve rather than an independently verified Klippel scan, so treat the extension figures as directionally useful rather than as precise as the ASR-measured entries in this category.
Buy the Monolith THX-365IW. It is rated higher for sound quality than the KEF CI200RR-THX and costs less, so only choose the other one for a particular feature it does better.
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Specifications Side By Side
| Monolith THX-365IW | KEF CI200RR-THX | |
|---|---|---|
| Price | $999.98 per pair | $2,399.98 per pair |
| Ranked | #8 of 28 in In-Wall & In-Ceiling Speakers | #12 of 28 in In-Wall & In-Ceiling Speakers |
| Drivers | 2x 6.5” high-excursion long-fiber pulp cone woofers, 2” silk dome midrange, 1” silk dome tweeter (3-way) | 8” woofer, 1.5” Uni-Q tweeter (2.2kHz crossover) |
| Enclosure | In-wall, passive 3-way with dog-ear mounting tabs | Open-backed, in-ceiling |
| Dimensions | 22.7”H x 11.1”W x 3.8”D (577 x 282 x 97 mm) | 11.4” x 11.4” x 5.2” (290 x 290 x 132.6 mm) (126.5mm mounting depth) |
| Weight | 19.6 lbs (8.9 kg) | 7.9 lbs (3.6kg) |
| Sensitivity | 89.5dB | 90dB |
| Impedance | 4 ohms nominal (about 2.9 ohm minimum) | 4 ohms |
| Power Handling | 160W maximum | 10-190W recommended amplifier power |
| Crossover Frequency | 550Hz, 1,900Hz (4th-order Linkwitz-Riley) | - |
| Warranty | 5 years | - |
| Certification | THX Ultra | THX |
| Bass Extension (-3dB) | 54.6Hz (measured, Audio Science Review) | 82.5Hz (measured, spinorama.org vendor data) |
| Bass Extension (-10dB) | 31.1Hz (measured, Audio Science Review) | 30.5Hz (measured, spinorama.org vendor data) |
| Spinorama Preference Score | 5.23 | - |
| Spinorama Preference Score with Perfect Sub | 7.64 | - |
| DIY Kit | No | No |
| Mounting Cutout | - | 238mm (9.37 in) |
| Frequency Response | - | 33Hz-28kHz +/-6dB (manufacturer, open-backed) |
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