The Monolith THX-365IW ranks #7 out of 14 total In-Wall & In-Ceiling Speakers for sound quality. See all Passive Home rankings for every top pick.
Brand: Monolith
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#7 Monolith THX-365IW: $999.98 per pair Amazon Monoprice eBay
Pros: Audio Science Review’s retest measured a preference score of 5.23, or 7.64 with a perfect subwoofer, with -3dB at 54.6Hz and -6dB at 42.8Hz, deep bass for an in-wall speaker. Directivity is well controlled (SPDI deviation 2.09dB) and on-axis smoothness is 0.70. It is a THX Ultra certified three-way, with two 6.5” woofers, a dedicated 2” silk dome midrange and a 1” silk dome tweeter, rated at 89.5dB sensitivity, which ASR’s measurement confirmed at 89.4dB. The 5-year warranty is longer than most in-wall speakers get. Measured bass extension of 54.6Hz (-3dB).
Cons: 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. Monoprice positions it for rear and surround channels and suggests in-room speakers up front, and the ASR reviewer said he would pick something better for a front left or right. Impedance dips to about 2.9 ohms, so the amplifier needs to be comfortable with a low load. At $500 each a stereo pair costs twice that.
How it compares: Just above it: KEF CI250RRM-THX - $2500 more, 0.5Hz lower bass extension (-3dB). Just below it: KEF CI200RR-THX - $700 more, 0.5Hz higher bass extension (-3dB).
| Bass Extension (-10dB) | 31.1Hz (measured, Audio Science Review) |
|---|---|
| Bass Extension (-3dB) | 54.6Hz (measured, Audio Science Review) |
| Certification | THX Ultra |
| Crossover Frequency | 550Hz, 1,900Hz (4th-order Linkwitz-Riley) |
| DIY Kit | No |
| Dimensions | 22.7”H x 11.1”W x 3.8”D (577 x 282 x 97 mm) |
| Drivers | 2x 6.5” high-excursion long-fiber pulp cone woofers, 2” silk dome midrange, 1” silk dome tweeter (3-way) |
| Enclosure | In-wall, passive 3-way with dog-ear mounting tabs |
| Impedance | 4 ohms nominal (about 2.9 ohm minimum) |
| Power Handling | 160W maximum |
| Sensitivity | 89.5dB |
| Spinorama Preference Score | 5.23 |
| Spinorama Preference Score with Perfect Sub | 7.64 |
| Warranty | 5 years |
| Weight | 19.6 lbs (8.9 kg) |
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