Short answer: the Revel W553L. It ranks #2 of 28 in-wall speakers by sound quality, rated 4.5/5, at $1,089.90. The Monolith THX-365IW ranks #8, rated 4.0/5, at $999.98, $89.92 cheaper, not enough of a saving to outweigh the sound-quality gap.
The Revel W553L is the better-sounding choice. An in-wall speaker with excellent, accurate sound for the money, a swiveling tweeter, and mounting for left, right or center. The tradeoff: At $545 each a stereo pair costs twice that, and a separate amplifier is required.
The Monolith THX-365IW is the deeper-bass pick. 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 64.5Hz for the Revel W553L. Watch for: 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.
Buy the Revel W553L. It is rated higher for sound quality, and saving $89.92 with the Monolith THX-365IW does not make up for the sound-quality gap.
Looking for alternatives? See the complete Passive Home rankings.
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Specifications Side By Side
| Revel W553L | Monolith THX-365IW | |
|---|---|---|
| Price | $1,089.90 per pair | $999.98 per pair |
| Ranked | #2 of 28 in In-Wall & In-Ceiling Speakers | #8 of 28 in In-Wall & In-Ceiling Speakers |
| Drivers | 2x 5.25” micro-ceramic composite (MCC) woofers, 1” swiveling aluminum dome tweeter with waveguide | 2x 6.5” high-excursion long-fiber pulp cone woofers, 2” silk dome midrange, 1” silk dome tweeter (3-way) |
| Enclosure | In-wall, LCR (vertical or horizontal mounting) | In-wall, passive 3-way with dog-ear mounting tabs |
| Mounting Cutout | 163W x 359H mm | - |
| Dimensions | 15.1”H x 7.4”W (384 x 188 mm) (74mm mounting depth) | 22.7”H x 11.1”W x 3.8”D (577 x 282 x 97 mm) |
| Weight | 7.7 lbs (3.5 kg) | 19.6 lbs (8.9 kg) |
| Sensitivity | 90dB | 89.5dB |
| Power Handling | 10-150W recommended amplifier power | 160W maximum |
| Warranty | Lifetime | 5 years |
| Bass Extension (-3dB) | 64.5Hz (measured, Erin’s Audio Corner) | 54.6Hz (measured, Audio Science Review) |
| Bass Extension (-10dB) | 39.3Hz (measured, Erin’s Audio Corner) | 31.1Hz (measured, Audio Science Review) |
| Spinorama Preference Score | 4.84 | 5.23 |
| Spinorama Preference Score with Perfect Sub | 7.50 | 7.64 |
| DIY Kit | No | No |
| Impedance | - | 4 ohms nominal (about 2.9 ohm minimum) |
| Crossover Frequency | - | 550Hz, 1,900Hz (4th-order Linkwitz-Riley) |
| Certification | - | THX Ultra |
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