The SUB 708-AS mk3 is a portable 18" high-power active subwoofer for live sound applications.
Read moreAt a glance
All specifications- Frequency response
- 35 Hz to 120 Hz
- Weight
- 40.6 kg
- Max SPL @ 1m
- 133 dB
- Woofer
- 1 x 18'', 3.0'' v.c
- Input signal
- bal/unbal
- Input connectors
- XLR
Overview
The SUB 708-AS mk3 is a portable 18" high-power active subwoofer for live sound applications. It features a state-of-the-art transducer with a high-power ceramic magnetic circuit and a powerful Class-D amplifier that delivers sound pressure levels up to 133 dB with exceptional headroom. Designed as the ideal complement for 8" or 10" loudspeakers, it provides outstanding performance in any application. Rear panel controls include volume, EQ, polarity, and crossover frequency selection. The rugged all-wood cabinet with scratch-resistant polyurea coating makes it durable, easy to carry and install securely. With its versatility, sound quality, and high power output, the SUB 708-AS MK3 is perfect for small to mid-sized venues and portable applications.
Highlights
- 1400 Watt Class-D Amplifier
- 18” Woofer, bass reflex housing
- Stereo Crossover
- Switchable Crossover Frequencies
- Polarity-reverse switch
- Electronic equalization, soft limiter and protection
- Stereo XLR input, Stereo XLR signal output
- Bass Motion Control excursion management
About RCF
RCF’s passion for perfection drives the design of every product to create enlightening, unique, and delightful experiences for our customers. All speakers and components are designed from the ground up and developed internally to maximize the end result. Our extensive catalog covers all aspects of the audio chain and meets the needs of musicians, sound engineers, rental companies, architects, and system integrators. Whatever your audio requirement is, we have the right solution.
All RCF productsFeatures
4

Legendary subwoofers
RCF subwoofers are the first choice of many sound engineers, thanks to the very high SPL levels at very low frequencies, small dimensions compared to the competitors, self-powered design, long-term reliability, and impressive size/weight to SPL output ratio. Your crowd will be able to live an engaging immersive experience in both live sound or DJing applications.

Power That Moves
RCF's improvements in transducer design make them stronger and more powerful so the amplifier follows the evolution. With 1400W peak power, the Class-D amplifier manages extreme sound pressure levels with an ultra-fast attack, realistic transient response, and very low heat loss. The speaker design is energy-efficient so there's no need for a cooling fan. The amplifier is attached to a solid aluminum heat exchanger in the rear of the cabinet with no moving parts. The stereo input circuit with crossover features a new low distortion design with an advanced safety limiter, maintaining the true character of the input signal at all levels. RCF amplifiers are designed according to EN62368-1 for maximum safety and present a Switch Mode Power Supply section joining high-efficiency with minimum weight. SUB 7 Series subwoofers can be configured from the rear panel, and features a full set of commands: - X-OVER PRESET 80Hz/120Hz - POLARITY REVERSE - OUT SIGNAL, LINE / HIGH PASS
Bass Motion Control
When searching for an extended bass with enhanced performance, RCF engineers found a way to remove the high-pass filter, replacing it with a forward-thinking approach. Introducing BMC (Bass Motion Control), the newly advanced woofer excursion management feature. The speaker equipped with BMC can handle the lowest audible frequencies without affecting the woofer stability, with extended linearity and better sound integrity. The BMC method works by creating a complete map of the dynamic behavior of the woofer, to generate a custom algorithm that only limits over-excursions. This gives total freedom of signal reproduction to the transducer. When high-pass filters normally protect the woofer motion from becoming destructive but change the phase behavior, the new BMC algorithm breaks conventional rules.

Tour-Ready Workhorse
The subwoofer is suitable for a wide range of live sound applications. The rugged all-plywood cabinet is easy to carry and stack, due to its light-weight. All are equipped with ergonomic handles with rubber grips for easy set-up and tear down. The M20 threaded pole mount on the top allows the cabinet to support speakers with a pole mount. The heavy-duty polyurea coating, the powder-coated metal grille, and the rugged structure of the cabinet withstand long-term use and transportation. Separate housing for the amplifier guarantees component efficiency and reliability. An acoustically transparent sound foam backing on the inside of the grille ensures protection from dust and humidity. With its frontal vented ports, the subwoofer can also be used in recessed spaces.
Specifications
- Frequency response
- 35 Hz to 120 Hz
- The range of pitches it reproduces, from deep bass to the top of the treble.
- Weight
- 40.6 kg
- Per unit, out of the box.
- Model code
- RCF-SUB-708-AS-MK3
- Quote it when you ask a specialist.
Acoustical specifications
- Frequency Response
- 35 Hz - 120 Hz
- Max SPL @ 1m
- 133 dB
Transducers
- Woofer
- 1 x 18'', 3.0'' v.c
Input/Output section
- Input signal
- bal/unbal
- Input connectors
- XLR
- Output connectors
- XLR
- Input sensitivity
- -2 dBu/+4 dBu
Processor section
- Hi-Pass Frequencies
- 110 Hz
- Low-Pass Frequencies
- 80 Hz
- Protections
- Thermal, RMS
- Limiter
- Soft Limiter
- Controls
- Volume, EQ, Phase, Xover
Power section
- Total Power
- 1400 W Peak, 700 W RMS
- Low frequencies
- 1400 W Peak, 700 W RMS
- Cooling
- Convection
- Connections
- VDE
Standard compliance
- Safety agency
- CE compliant
Physical specifications
- Cabinet/Case Material
- Baltic birch plywood
- Handles
- One each side
- Pole mount/Cap
- M20 thread
- Grille
- Steel with clothing
- Color
- Black
Size / Weight
- Height
- 693 mm / 27.28 inches
- Width
- 505 mm / 19.88 inches
- Depth
- 685 mm / 26.97 inches
- Weight
- 40.6 kg / 89.51 lbs
Shipping information
- Package Height
- 735 mm / 28.94 inches
- Package Width
- 565 mm / 22.24 inches
- Package Depth
- 745 mm / 29.33 inches
- Package Weight
- 45.6 kg / 100.53 lbs
Mains
- Mains voltage
- 220-240V
Downloads
5
- SUB 708-AS MK3 User manualManual · English · PDF, 2.1 MBDownload
- SUB 708-AS MK3 SpecsheetDatasheet · English · PDF, 1.6 MBDownload
- SUB 708-AS MK3 Line art 2DDrawing · English · PDF, 297 KBDownload
- SUB 708-AS MK3 CE declaration of conformityCertificate · English · PDF, 57 KBDownload
- SUB 708-AS MK3 UKCA declaration of conformityCertificate · English · PDF, 63 KBDownload
More from RCF
RCFSUB 15-ASPrice on request
RCFSUB 18-ASPrice on request
RCFSUB 702-AS MK3Price on request
RCFSUB 705-AS MK3Price on request
NewRCFSUB 8004-ASPrice on request
RCFSUB 8006-ASPrice on request
RCFSUB 8008-ASPrice on request
NewRCFSUB 808-AS BlackPrice on request
NewRCFSUB 9016-ASPrice on request
RCFSUB 9019-ASPrice on request
RCFSUB 9029-ASPrice on request
RCFHDL 12-ASPrice on request
Similar products
FocalSub OnePrice on request
FocalSUB12Price on request
Dynaudio18SPrice on request
Dynaudio9SPrice on request
DynaudioCore SubPrice on request
DynaudioCore Sub CompactPrice on request
DynaudioMS15Price on request
DynaudioMS18Price on request
TannoyDCS115BPrice on request
TannoySAT SUBPrice on request
TannoySAT SUB-WHPrice on request
TannoyVSX 10BPPrice on request










