The JBL Synthesis SCL-6 ranks #8 out of 18 total In-Wall & In-Ceiling Speakers for sound quality. See all Passive Home rankings for every top pick.
Brand: JBL
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#8 JBL Synthesis SCL-6: $3,629.90 per pair Audio Advice eBay
Pros: Erin’s Audio Corner measured it with a very tight 1.2dB reference band and 0.67 listening-window smoothness, and its preference score rises from 3.92 to 6.71 with a subwoofer. Four 5.25-inch aluminum woofers around a 2410H-2 compression driver on JBL’s imaging horn give 91dB sensitivity and high output, with an 80 degree by 80 degree treble coverage pattern that keeps directivity consistent. Bass measures 67.4Hz at -3dB and about 40.8Hz at -10dB in free air, before the extra wall reinforcement of an in-wall install. Measured bass extension of 67.4Hz (-3dB).
Cons: Bass is limited without a subwoofer, and a 3.92 standard score trails the best in-wall speakers here. Average on-axis deviation of 0.49dB is rougher than the Revel in-walls. The 4 ohm load and 766mm tall cutout need a capable amplifier and a tall wall cavity, and at $1815 each it is sold mainly through custom-installation dealers.
How it compares: Just above it: Monolith THX-365IW - $1315 cheaper, 1.5Hz lower bass extension (-3dB). Just below it: KEF CI200RR-THX - $615 cheaper, 1Hz lower bass extension (-3dB).
| Bass Extension (-10dB) | 40.8Hz (measured, spinorama.org Erin’s Audio Corner data) |
|---|---|
| Bass Extension (-3dB) | 67.4Hz (measured, spinorama.org Erin’s Audio Corner data) |
| Crossover Frequency | 1.8kHz |
| DIY Kit | No |
| Dimensions | 31.3”H x 7.3”W x 3.8”D (796 x 185 x 97 mm) (92mm mounting depth) |
| Drivers | Four 5.25” aluminum matrix cone woofers, 1” 2410H-2 compression driver on HDI horn (2.5-way) |
| Enclosure | In-wall, open back |
| Frequency Response | 50Hz-30kHz -6dB (manufacturer, 2pi) |
| Impedance | 4 ohms |
| Mounting Cutout | 157 x 766mm (6.18 x 30.18 in) |
| Power Handling | 25-200W recommended amplifier power |
| Sensitivity | 91dB (2.83V/1m, 2pi anechoic) |
| Spinorama Preference Score | 3.92 |
| Spinorama Preference Score with Perfect Sub | 6.71 |
| Weight | 22.2 lbs (10.07 kg) |
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