Short answer: the Miller & Kreisel IW150. It ranks #13 of 18 in-wall speakers by sound quality, rated 3.6/5, at $4,998; the MartinLogan Tribute 5XW ranks #17, rated 3.2/5, and costs $6,999.98, which makes this an easy call rather than a real tradeoff.
Why pick the Miller & Kreisel IW150: Erin’s Audio Corner’s Klippel measurement shows well controlled directivity (SPDI deviation 2.43dB) and a smooth predicted in-room response, with a preference score of 2.88, or 6.32 with a perfect subwoofer. The tradeoff: Bass is thin: measured -3dB is 95.2Hz and -6dB is 82.0Hz, and Miller & Kreisel rates it only to 80Hz, so a subwoofer is required, and even with a perfect subwoofer the score reaches only 6.32.
What the MartinLogan Tribute 5XW does well: Erin’s Audio Corner’s Klippel measurement shows a rated 94dB sensitivity that measured a still efficient 88.1dB at 1 meter, so it plays loudly for its size. The catch: The measurement is the weakest of the in-wall speakers here: a preference score of 1.84, or just 4.91 with a perfect subwoofer, with on-axis smoothness of 0.30, an average on-axis deviation of 1.56dB and wide directivity swings (SPDI deviation 3.25dB).
Buy the Miller & Kreisel IW150. It is rated higher for sound quality than the MartinLogan Tribute 5XW and costs less, so it is the default pick unless a specific strength of the other one matters more to you.
Looking for alternatives? See the complete Passive Home rankings.
Specifications Side By Side
| Miller & Kreisel IW150 | MartinLogan Tribute 5XW | |
|---|---|---|
| Price | $4,998 per pair | $6,999.98 per pair |
| Ranked | #13 of 18 in In-Wall & In-Ceiling Speakers | #17 of 18 in In-Wall & In-Ceiling Speakers |
| Drivers | 2x 5.25” polypropylene bass/midrange drivers, 3x 1” soft fabric dome tweeters | 1.25 x 2.4” Folded Motion XT Obsidian tweeter, 2x 5.25” carbon fiber woofers, 2x 6.5” passive radiators |
| Enclosure | In-wall | Sealed back box, in-wall |
| Mounting Cutout | 288W x 331H mm | 236W x 757H mm |
| Dimensions | 13.9”H x 12.2”W (354 x 311 mm) baffle (95mm mounting depth) | 31.1”H x 10.6”W x 4.1”D (791 x 269 x 104 mm) (97mm mounting depth) |
| Weight | 18.7 lbs (8.5 kg) | 25.6 lbs (11.6 kg) |
| Sensitivity | 90dB | 94dB (manufacturer), 88.1dB (measured, Erin’s Audio Corner) |
| Impedance | 4 ohms | 4 ohms |
| Power Handling | 25-400W recommended amplifier power | 20-250W recommended amplifier power |
| Frequency Response | 80Hz-20kHz +/-3dB (manufacturer) | 71Hz-25kHz +/-3dB (manufacturer) |
| Bass Extension (-3dB) | 95.2Hz (measured, Erin’s Audio Corner) | 74.7Hz (measured, Erin’s Audio Corner) |
| Bass Extension (-10dB) | 68.7Hz (measured, Erin’s Audio Corner) | 68.3Hz (measured, Erin’s Audio Corner) |
| Spinorama Preference Score | 2.88 | 1.84 |
| Spinorama Preference Score with Perfect Sub | 6.32 | 4.91 |
| DIY Kit | No | No |
| Crossover Frequency | - | 2,250Hz |
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Prices on this page were last checked September 26, 2026 at 11:14 PM 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
Miller & Kreisel IW150: $4,998 per pair Audiolab (authorized M&K dealer) eBay
Pros: Erin’s Audio Corner’s Klippel measurement shows well controlled directivity (SPDI deviation 2.43dB) and a smooth predicted in-room response, with a preference score of 2.88, or 6.32 with a perfect subwoofer. The unusual layout puts two 5.25” polypropylene woofers beside a column of three 1” soft dome tweeters, a design meant to give even coverage across a room from a single wall opening. It is rated at 90dB sensitivity, and Erin’s measurement computed a real 88.2dB, and it accepts 25-400W of amplifier power. Measured bass extension of 95.2Hz (-3dB).
Cons: Bass is thin: measured -3dB is 95.2Hz and -6dB is 82.0Hz, and Miller & Kreisel rates it only to 80Hz, so a subwoofer is required, and even with a perfect subwoofer the score reaches only 6.32. On-axis smoothness is 0.48 and on-axis deviation averages 0.62dB, so the midrange is rougher than the better in-wall designs. At $2499 each a stereo pair costs twice that. Erin describes it as discontinued from what he can tell, so stock may be limited to remaining inventory.
Full Miller & Kreisel IW150 review and specifications →
| Bass Extension (-10dB) | 68.7Hz (measured, Erin’s Audio Corner) |
|---|---|
| Bass Extension (-3dB) | 95.2Hz (measured, Erin’s Audio Corner) |
| DIY Kit | No |
| Dimensions | 13.9”H x 12.2”W (354 x 311 mm) baffle (95mm mounting depth) |
| Drivers | 2x 5.25” polypropylene bass/midrange drivers, 3x 1” soft fabric dome tweeters |
| Enclosure | In-wall |
| Frequency Response | 80Hz-20kHz +/-3dB (manufacturer) |
| Impedance | 4 ohms |
| Mounting Cutout | 288W x 331H mm |
| Power Handling | 25-400W recommended amplifier power |
| Sensitivity | 90dB |
| Spinorama Preference Score | 2.88 |
| Spinorama Preference Score with Perfect Sub | 6.32 |
| Weight | 18.7 lbs (8.5 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons
MartinLogan Tribute 5XW: $6,999.98 per pair Audio Advice eBay
Pros: Erin’s Audio Corner’s Klippel measurement shows a rated 94dB sensitivity that measured a still efficient 88.1dB at 1 meter, so it plays loudly for its size. The folded thin-film Folded Motion XT Obsidian tweeter rotates for horizontal or vertical mounting, and it pairs two carbon fiber woofers with two 6.5” passive radiators in a sealed box. It accepts 20-250W of amplifier power and mounts with a slim 3.8” depth behind the wall. Measured bass extension of 74.7Hz (-3dB), with a measured sensitivity of 94dB.
Cons: The measurement is the weakest of the in-wall speakers here: a preference score of 1.84, or just 4.91 with a perfect subwoofer, with on-axis smoothness of 0.30, an average on-axis deviation of 1.56dB and wide directivity swings (SPDI deviation 3.25dB). Bass measured -3dB at only 74.7Hz, so a subwoofer is required, and MartinLogan rates it to 71Hz. At $3500 each a stereo pair costs twice that and MartinLogan sells it through dealers.
Full MartinLogan Tribute 5XW review and specifications →
| Bass Extension (-10dB) | 68.3Hz (measured, Erin’s Audio Corner) |
|---|---|
| Bass Extension (-3dB) | 74.7Hz (measured, Erin’s Audio Corner) |
| Crossover Frequency | 2,250Hz |
| DIY Kit | No |
| Dimensions | 31.1”H x 10.6”W x 4.1”D (791 x 269 x 104 mm) (97mm mounting depth) |
| Drivers | 1.25 x 2.4” Folded Motion XT Obsidian tweeter, 2x 5.25” carbon fiber woofers, 2x 6.5” passive radiators |
| Enclosure | Sealed back box, in-wall |
| Frequency Response | 71Hz-25kHz +/-3dB (manufacturer) |
| Impedance | 4 ohms |
| Mounting Cutout | 236W x 757H mm |
| Power Handling | 20-250W recommended amplifier power |
| Sensitivity | 94dB (manufacturer), 88.1dB (measured, Erin’s Audio Corner) |
| Spinorama Preference Score | 1.84 |
| Spinorama Preference Score with Perfect Sub | 4.91 |
| Weight | 25.6 lbs (11.6 kg) |
- Links
- Reviews, Comparisons and Sound Samples
- Head-to-Head Comparisons