The Focal Sub6 is an active subwoofer (1 x 350W RMS built-in amplifier with BASH technology) for professional monitoring systems. The driver is an 11" Focal with a W sandwich composite cone loaded by a large section laminar port. It can be used both as LFE channel in a surround system or, as a bass or sub-bass complement in a stereo system (2.1 or 2.2). The Sub6 was designed to allow optimum acoustic coupling with professional monitoring speakers. Therefore, it includes all the features to achieve this task, such as stereo high-pass filter (75Hz or 100Hz) for the left and right satellites, low-pass filter (adjustable) with mono summation, phase inverter, phase fine tuning, mute switch, 2.1 bypass with a footswitch remote control (not included), as well as a wiring panel, rich with possibilities.

The W cone

Focal has been developing composite sandwich cone technology for over 15 years. The "W" process (glass/foam/glass), used on the SM11, SM8 and SM6 lines, provides a true optimization of the frequency response by fine tuning of mass, rigidity and damping parameters. The balance between these three fundamental—and often contradictory—parameters is foundation of the outstanding sound neutrality of these speakers.

The 10-5/8" Focal speaker is equipped with a high excursion system to enable accurate and extended reproduction in the bass/infra-bass register. The 2-5/8" diameter and 1-1/4" high voice coil ensures a perfect mechanical coupling and a total control of the driver, even at high sound level. The magnetic construction made of double ferrite and large field and back plates offers high symmetrical magnetic field to keep dynamics, even at very low frequency.

A custom-designed amplification stage

Designing an amp to be integrated inside a speaker requires a very different set of rules than for a traditional amp. Speaker size and cooling concerns are often in contradiction to the high-quality and high-power requirements of a sonically transparent speaker.

Focal's engineers used BASH technology to develop the bass/medium amplification circuit for the SM6 professional line of speakers. This was the only way to utilize the best of Class AB-style circuits (for exceptional quality) with a Class D-type yield, which is crucial when housing a 150W RMS circuit in such a small space (300W RMS for the Twin6 Be and 350W RMS for the Sub6).