Short answer: choose between the FBT J15A and RCF ART 735-A MK4 for the deployment, not from the automatic ranking alone. Their driver format, power requirements, coverage, bass reach, output capability, and control features determine which is the more practical PA for a particular room or system. The RCF ART 735-A MK4 is discontinued; its replacement is the RCF ART 735-A MK5.
The case for the FBT J15A. Medium-quality vendor data shows a 3.87 ideal-subwoofer preference score with 61Hz measured extension, extending the compact, wedge-capable J-series design used by the J12A and J8A to a 15-inch woofer.
The case for the RCF ART 735-A MK4. Its large 3-inch compression-driver voice coil, 132dB claimed peak and roughly 53Hz measured extension give it useful vocal headroom and bass reach. The 47.2 lbs (21.4 kg) enclosure remains manageable for a 15-inch box.
Important trade-offs. The preference score is on the lower end for this ranking, and detailed coverage, SPL and weight figures were not confirmed in local data. The low-quality vendor data is truncated and does not yield a preference score. It is discontinued and eclipsed by current 9-series and MK5 models.
Buy the FBT J15A when its stated format, coverage, and system features fit the job better.
Buy the RCF ART 735-A MK4 when its stated output, control, and deployment strengths better match the system.
Want more options? Browse the full PA & Live Sound rankings.
A compact, budget friendly powered 15 inch PA speaker whose wedge shaped cabinet can also work as a floor monitor.
A discontinued powered 15 inch PA speaker with strong vocal headroom and decent bass reach in a manageable cabinet.
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Specifications Side By Side
| FBT J15A | RCF ART 735-A MK4 | |
|---|---|---|
| Price | $563 | $888.00 Discontinued |
| Ranked | #46 of 76 in 15-Inch PA Speakers | #51 of 76 in 15-Inch PA Speakers |
| Passive | No | No |
| Configuration | Active 2-way bass-reflex PA speaker | Active 2-way bass-reflex PA speaker |
| Drivers | 15” woofer, compression driver | 15” woofer, 1.4” compression driver with 3” voice coil |
| Dimensions | 26.1”H x 16.1”W x 15.2”D (663 x 410 x 387 mm) | 27.9”H x 17.2”W x 15.3”D (708 x 437 x 389 mm) |
| Crossover Frequency | 1.8kHz (manufacturer specified) | 800Hz (manufacturer specified) |
| Frequency Response | 48Hz - 20kHz (manufacturer specified) | 45Hz - 20kHz (manufacturer specified) |
| Inputs | XLR/jack input with link output | XLR/jack combo input; XLR output |
| Amplifier Power | 450W RMS (350W LF + 100W HF); 900W peak (700W LF + 200W HF) | 1,400W peak / 700W RMS (1,000W LF + 400W HF peak, manufacturer specified) |
| Cabinet Material | Polypropylene | Polypropylene composite |
| Rigging | Two M10 fly points; pole socket | Two M10 fly points; pole mount |
| Bass Extension (-3dB) | 63Hz (measured, vendor Spinorama data) | 53Hz (measured, vendor Spinorama data) |
| DSP | Yes | Yes, FiRPHASE, EQ, limiting and protection |
| Bluetooth | No | No |
| Spinorama Preference Score | 1.16 | - |
| Spinorama Preference Score with Perfect Sub | 3.87 | - |
| XLR Input | Yes | Yes |
| RCA Input | No | No |
| TRS Input | Yes | Yes |
| Optical Input | No | No |
| Coaxial Input | No | No |
| USB Input | No | No |
| HDMI Input | No | No |
| AES Input | No | No |
| Aux Input | No | No |
| Microphone Input | No | No |
| Guitar Input | No | No |
| Maximum SPL | 129dB (manufacturer specified) | 132dB peak (manufacturer specified) |
| Coverage | 90° x 60° | 100° x 60° |
| Weight | 33.3 lbs (15.12 kg) | 47.2 lbs (21.4 kg) |
Frequency Response Compared
Both speakers’ spinorama measurements, overlaid. A flatter line is more neutral: peaks sound forward or harsh, dips sound recessed. Each curve is shifted so its average from 300 Hz to 3 kHz sits at 0 dB, so loudness differences between the two are removed and only the shape is compared.
Measurement data: FBT J15A (measured by the manufacturer) and RCF ART 735-A MK4 (measured by the manufacturer), via spinorama.org.
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