Systems ListRythmik AudioFV15HP

ManufactureRythmik Audio
System typeVented
Driver Size15 "
Number of drivers1
Internal volume5 ft3
External volume6.5 ft3
Dimentions (Width ◊ Height ◊ Depth)18 " ◊ 24 " ◊ 26 "
Weight110 lbs
Native Tuning Frequency14 Hz
Power600 W


The FV15HP is a 15" bass reflex system which employs Rythmik's proprietary servo control system. The feedback system uses a thin feedback coil positioned directly under the primary voice coil which is used to return information about the active voice coilís resultant signal. The feedback coil is slightly longer than the primary coil so it has a better degree of linear accuracy relative to the primary at high excursion. The servo design monitors this signal from the feedback coil and introduces correction dynamically back into the primary coil. Ideally the correction is designed to keep the driver necessarily in a steady state (e.g. stable) and reduce distortion from non-linear effects. The combination of servo control and a bass reflex subwoofer is a little unusual considering the driver's impedance and excursion are no longer dependent to the frequency response as they are in a sealed design, but this system boasts some solid performance so our initial skepticism has been subdued.

The FV15HP is medium to large sized for a commercial HT subwoofer with two 3.5" flared ports and the 15" driver all mounted to the front panel. The unit is heavy at 110lbs and comes in a variety of home theater style veneers. The amplifier features an unusually large assortment of controls for varying the extension, filtering and damping and includes the unique servo feedback system. The enclosure is well braced and sturdy and the driver is a quality unit employing the popular 12 spoke basket, an aluminum cone and dual spiders. The motor is a moderate sized double stacked ferrite array which powers a 3.5" nominal diameter voice coil and employs shorting rings to limit inductance. The driver and other components of the subwoofer are also available to DIY'ers for purchase separately. The subwoofer can be operated in either 2 ports open mode for higher output or 1 port open mode for deeper extension.