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RCF SUB 905-AS MK3 Active PA Subwoofer

The RCF SUB 905-AS MK3 is a high-performance 15-inch active subwoofer designed for professional sound reinforcement applications. Featuring a 2200 W Class D amplifier and a bass reflex housing, it delivers a maximum sound pressure level of 133 dB with integrated thermal and RMS protection.

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Overview and Design

The RCF SUB 905-AS MK3 represents a modern iteration of RCF's compact, high-output subwoofer range. Housed in a durable plywood cabinet, the unit is engineered to withstand the rigours of touring and frequent transport. It utilises a bass reflex design to optimise low-frequency extension and air movement, providing a punchy and controlled response. The core of the unit is the RCF Precision Transducer, a proprietary driver known for its efficiency and high power handling capabilities.

Amplification and Processing

Internal power is provided by a 2200 W Class D amplifier, which offers significant headroom and ensures the system can reach its maximum SPL of 133 dB without excessive distortion. To maintain reliability during prolonged use, RCF has implemented an advanced protection suite. This includes thermal limiting to prevent overheating, RMS limiting to protect the driver from sustained over-excursion, and a soft audio limiter designed to prevent digital clipping and maintain consistent audio quality.

System Integration

For precise integration into various PA setups, the SUB 905-AS MK3 features an onboard stereo crossover. This allows the user to select specific frequencies, ensuring a seamless transition between the subwoofer and full-range satellite speakers. Users can also adjust volume, EQ, and phase settings directly on the unit. These controls facilitate better phase alignment and a wider stereo image, making it adaptable to different acoustic environments and speaker combinations.

Target Audience and Applications

This subwoofer is suited for mobile DJs, live bands, and rental companies requiring a balance between portable size and high-output performance. Its rugged construction makes it a viable choice for touring professionals. While it performs exceptionally as a standalone low-end supplement, it is particularly effective when paired with mid-high units such as the RCF ART 735-A MK5 or the RCF NX 915-SMA to create a cohesive, full-range professional sound system.

Market Comparisons

When compared to alternatives in the market, the SUB 905-AS MK3 sits as a premium professional option. While compact models like the AVCOM 8" or budget-friendly options like the SubZero P15X offer entry-level solutions, the RCF provides significantly higher SPL and more sophisticated internal DSP. Compared to larger units like the QSC KLA181 18" subwoofer, the RCF SUB 905-AS MK3 offers a more compact footprint while maintaining a competitive power-to-weight ratio, suitable for venues where space is a consideration.

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Frequently asked questions

What is the peak power output of the RCF SUB 905-AS MK3?
The subwoofer features a high-efficiency Class D amplifier capable of delivering 2200 W peak power. This provides the necessary headroom for clear, high-impact bass reproduction.
What is the maximum SPL rating for this unit?
The RCF SUB 905-AS MK3 is capable of reaching a maximum Sound Pressure Level (SPL) of 133 dB. This ensures sufficient volume for medium to large-sized venues.
Does the subwoofer include a built-in crossover?
Yes, it features an onboard stereo crossover with switchable frequencies. This allows for precise integration with different full-range speakers to ensure a balanced frequency response.
What material is used for the cabinet construction?
The cabinet is constructed from rugged plywood. This material is chosen for its durability and acoustic properties, making it suitable for professional touring and frequent use.
What safety features protect the amplifier and driver?
The unit includes comprehensive protection circuitry, including thermal limiting and RMS limiting. It also features a soft audio limiter to prevent signal clipping and maintain audio consistency.
What is the size of the woofer in this model?
The SUB 905-AS MK3 is equipped with a cutting-edge 15-inch RCF Precision Transducer. This driver is designed for high efficiency and extended low-frequency response.
Can I adjust the phase of the subwoofer?
Yes, the rear panel includes phase controls. This allows users to align the subwoofer's output with the satellite speakers to prevent phase cancellation in different environments.
Is this subwoofer active or passive?
This is an active (powered) subwoofer. It contains its own internal amplification and signal processing, requiring only a line-level input and a power source to operate.
What kind of enclosure design does it use?
It uses a bass reflex housing design. This configuration uses a tuned port to extend the bass response and increase efficiency at low frequencies.
What controls are available on the back of the unit?
The unit provides controls for volume, EQ, and phase, alongside the switchable crossover frequencies. These options allow for detailed customisation of the subwoofer's output.
How much does the RCF SUB 905-AS MK3 typically cost?
The typical price for this model is approximately £1242. This reflects its position as a professional-grade piece of audio equipment.
Which full-range speakers pair well with this subwoofer?
It is designed to work effectively with various professional speakers, such as the RCF ART 735-A MK5 or the RCF NX 915-SMA, to create a high-fidelity PA system.