JBL Synthesis SCL-4 Review: Rated 3.6/5

The JBL Synthesis SCL-4 is rated 3.6/5 for sound quality, #16 of 28 In-Wall & In-Ceiling Speakers. See all Passive Home rankings for every top pick.

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Brand: JBL

#16 JBL Synthesis SCL-4: $7,259.90 per pair Audio Advice $3,629.95 eBay

Same family: the JBL Synthesis SCL-6 (larger in-wall, ranked higher, rated 3.9/5), the JBL Synthesis SCL-3 (larger in-wall, ranked higher, rated 3.7/5), the JBL Synthesis SCL-7 (larger in-wall, ranked higher, rated 3.7/5), the JBL Synthesis SCL-1 (larger in-wall, ranked higher, rated 3.7/5) and the JBL Synthesis SCL-5 (larger in-wall, ranked lower, rated 2.5/5).

Pros: A compact in-wall speaker with a horn tweeter, very even coverage and bi-amp terminals for custom theater installs. 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 JBL Synthesis SCL-6.

Is the JBL Synthesis SCL-4 right for you?

Buy it if

• you have a modest amplifier (91 dB sensitivity is easy to drive).

Skip it if

• you want the best value: the higher-rated Revel W553L costs about $6,170 less.

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)

• Links
  • JBL Synthesis SCL-4 Official Page
• Reviews, Comparisons and Sound Samples
  • JBL Measurements (spinorama.org)

Head-to-Head Comparisons

7 comparisons

• JBL Synthesis SCL-4 vs Miller & Kreisel IW150
• JBL Synthesis SCL-4 vs JBL Synthesis SCL-1
• JBL Synthesis SCL-4 vs JBL Synthesis SCL-3
• JBL Synthesis SCL-4 vs Revel W990
• JBL Synthesis SCL-4 vs Grimani Systems Rixos-L
• JBL Synthesis SCL-4 vs MartinLogan Tribute 5XW
• JBL Synthesis SCL-4 vs Revel W228Be

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