The JBL Synthesis SCL-4 ranks #12 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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#12 JBL Synthesis SCL-4: $7,259.90 per pair Audio Advice eBay
Pros: JBL’s own measurements show a 1.85 directivity-index deviation, the most even directivity of the JBL Synthesis in-walls, with 0.35dB average on-axis deviation. The preference score rises from 3.56 to 6.55 with a subwoofer. A 7-inch aluminum woofer and 2409H compression driver on JBL’s imaging horn give 91dB sensitivity, and bi-wire and bi-amp terminals suit custom home theaters. Measured bass extension of 83.7Hz (-3dB).
Cons: Bass is the weakest here, at 83.7Hz for -3dB and about 61.9Hz for -10dB in free air, so it needs a subwoofer. Listening-window smoothness is 0.59 inside a 3.1dB reference band, and the data is manufacturer supplied and digitized from graphs. At $3630 each it costs twice as much as the better-measuring SCL-6.
How it compares: Just above it: JBL Synthesis SCL-7 - $2420 cheaper, 3Hz lower bass extension (-3dB). Just below it: Miller & Kreisel IW150 - $1131 cheaper, 1Hz lower bass extension (-3dB).
| Bass Extension (-10dB) | 61.9Hz (measured, JBL data on spinorama.org) |
|---|---|
| Bass Extension (-3dB) | 83.7Hz (measured, JBL data on spinorama.org) |
| Crossover Frequency | 1.3kHz |
| DIY Kit | No |
| Dimensions | 25”H x 16.1”W x 3.7”D (636 x 409 x 93 mm) |
| Drivers | 7” aluminum matrix cone woofer, 1” 2409H compression driver on HDI horn (2-way) |
| Enclosure | In-wall, integrated MDF back box |
| Frequency Response | 45Hz-33kHz -6dB (manufacturer, on-axis) |
| Impedance | 6 ohms |
| Power Handling | 200W RMS maximum recommended amplifier power |
| Sensitivity | 91dB (2.83V/1m) |
| Spinorama Preference Score | 3.56 |
| Spinorama Preference Score with Perfect Sub | 6.55 |
| Weight | 27.6 lbs (12.51 kg) |
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