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  F18 Direct Servo subwoofer
18" sealed audiophile sub with 900WRMS amplifier

Finesse meets brute force

Our servo technology is scalable to all subwoofer designs as well as driver size. F18 is our largest single driver sealed subwoofer to meet the needs for a high power home theater solution that retains the dynamic, accurate, and deep bass that we have become known for. Its max output at 20hz is at least 8db higher than that of our 12" sealed model F12 and more than 11db higher than our competitior's 12" model SB** measured by data-bass.com. The amplifier is based on Hypex audiophile class-D module. With the combination of the servo feedback and stiff aluminum cone, we have achieved lower distortion than competitor's 18" servo subwoofers (DD18+) with the same or even higher maximum SPL output from 10hz to 100hz , as tested at data-bass.com. In fact, F18 has recorded the lowest THD numbers at the maximum SPL output than any other subs tested. Our servo technology is scalable to all subwoofer designs as well as driver size.

Direct Servo Technology

All our subwoofers use our patented Direct Servo technology. The servo enables precise control over the cone which is essential for tight, dynamic and accurate bass. It also counteracts many different driver non-linearities and allows us to use lighter drivers which avoid the need for excessive amounts of amplifier power.

Some of the benefits of Direct Servo include:

  • Reduction of the effects of thermal compression are eliminated under normal operation
  • Higher efficiency allowing output which would normally require a more powerful amplifier
  • Deep bass extension can be achieved using a low mass driver with superior transient response
  • Mechanical and thermal memory effects are reduced, further improving transient response
  • The effective Q value is 0.1 resulting in much tighter and accurate bass than conventional designs
  • Dramatic reduction of the re-radiation of bass from inside the box

Read more about Direct Servo in our technology section.

View animation demonstrating how Direct Servo works >

HX1000XLR3 Amplifier and DS1820 Driver

F18 comes with a grille. The above photo is shown with grill taken off. It uses our new high power HX1000XLR3 servo amplifier and DS1820 driver. DS1820 features anodized aluminum cone, a 3" voice coil, and 240 oz magnet. Its linear excursion range is +/- 20mm.

The standard amplifier is HX1000XLR3. The quickguide of the XLR3 amplifier for vented subs can be found here . The F18 installation guide can be found here . The response curves with various extension frequency/damping combinations of both amplifiers can be found in our EQ page.

The sub comes with standard screw-in rubber feet. Chrome spike feet are sold separately.

The sale price includes UPS ground shipping to 48 US continental states only.

Holidays sale till end of the year for black oak/matte finish: $100 discount on single sub and $50 for multi-sub purchase. Price reflected in the shopping cart.

  Description: with 48 states shipping included Price  
  F18-SE piano black finish with HX1000XLR3 amplifier and black alu cone driver $1850 buy it now
  F18 black oak finish with HX1000XLR3 amplifier black alu cone driver and 48 states shipping $1630 buy it now
  F18 black matte finish with HX1000XLR3 amplifier black alu cone driver and 48 states shipping $1630 buy it now
  Change to silver cone driver for one F18 subwoofer $100 buy it now