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  F8 Direct Servo bass and midbass subwoofer
Sealed audiophile sub with dual 8" drivers

Features & Options

Product features include:

  • Patented Direct Servo technology >
  • 8" light weight cone mass high excursion driver >
  • Solid and very inert enclosure available in a range of finishing options >
  • Bass extension controls allowing adjustment of bass extension and excursion control >
  • Selectable 12/24 db/octave crossover filter slope >
  • Mini-XLR connection for better noise immunity (using mini-XLR input) >
  • 120V-240V switchable power >

Direct Servo technology

All our subwoofers feature our Direct Servo technology, which is our secret to achieving tight and accurate bass. The benefits are far more than simply achieving low distortion.

Direct Servo closed loop technology

Learn more in our technology articles >

Dual 8" cast frame paper cone high excursion drivers

Driver features include:

  • Low moving mass paper cone and foam surround to ensure an exceptional transient response
  • Large magnet for high flux density in the gap to ensure low distortion
  • Flux de-modulation shorting rings to lower inductance and improve linearity
  • Extended upper bandwidth response allowing up to 200hz crossover point (-6db at 250hz and therefore can be used for Linkwitz Riley for crossover point up to 250hz).

Quality enclosure

Our enclosures are very solid and well braced to minimize any cabinet resonance or coloration. The enclosure is heavily braced and the sub has a net weight of 53 lbs.

We also provide a range of finishes. Our range of attractive and excellent value vinyl finishes including:

  • black matte veneer
  • black oak veneer
  • piano black

Black piano gloss finish is also available in our signature edition.

Bass extension controls

F8 features a unique bass extension control, shown below.

The bass extension control enables the user to customize the frequency response of the low end for the best trade-off between output and extension. If set to low music, bass below 18 Hz will be filtered. The damping factor of this mode is 0.5 for the best time domain response. However, the disadvantage is slower attenuation of subsonic signals. For HT application, we recommend low-HT mode which incorporates a 3rd order highpass filter to filter out subsonic signals below 20hz. High extension setting is recommended for application where longer playback time and lower power consumption is required.

Crossover options

To suit different setups, we provide a 12 db and 24 db/octave crossover (as shown in the above photo) with adjustable range from 50hz to 200hz.

RCA input and mini-XLR input

120V-240 Switchable Voltage Selection

Correct voltage must be selected before use. Voltage switch is shown below.

voltage selection