SW-12-08FR Servo Sub Woofer
- Fs = 28 hertz
- Qms = 2.725
- Vas = 3.42 cu.ft or 96.94 liters
- Cms = 0.049 in/Ib
- Mms = 4.02 oz or 113.9 grams
- Rms = 15.57 Ibs/sec
- Xmax = 18 mm
- Sd = 76 sq.in or Dia = 9.83 in or 250 mm
- Qes = 1.028
- Re = 6.2 ohms
- Z = 8 ohms nominal
- BL = 11.21
- Pe = 200.0 watts (conservative rating)
- Qts = 0.747
- Sens = 85.6 dB (2.83 V)
The SW-12-08FR was specifically designed for applications operating in free air, on an open baffle, or in an infinite baffle application. This sub will deliver the ultimate in accuracy and sound quality and do so free from any box or enclosure colorations. It is also meant to be used with the Direct Servo plate amps.
No other sub-woofer system on the market offers this level performance in this application. With this sub-woofer system you will hear articulation and resolution in the low bass region far beyond standard passive systems regardless of how well the woofer is made. Distortion levels are also extremely low and well below other sub-woofer designs.
The SW-12-08FR gives new meaning to the terms fast bass. Fast bass has been a debatable term but really refers to a drivers ability to return back to a resting position. Any other sub must rely on the suspension alone to allow it to return back to a resting position. Any sub capable of playing down to the 20Hz range will also need a very heavy cone and a really low Fs. The heavy cone and its stored energy from the inertia of its movement make it difficult to quickly return to the resting position. The Direct Servo controlled sub can make use of a much lighter weight cone as the servo system will virtualize the parameters and add output as needed to maintain a flat response to below 20Hz even with a light weight cone that has a higher Fs. Not only does the light weight moving mass minimize the inertia but the Direct Servo control system effectively slams on the brakes electrically to much more quickly bring the woofer back to its resting position.
The SW-12-08FR has a nominal 8 ohm impedance and is designed to be used in pairs (paralleled) on a single Direct Servo amplifier. With two woofers being used there is considerable output (even in an open baffle design) and without the added expense of additional amplifiers. With two woofers sharing the load equally, higher SPL levels can be reached while still maintaining moderate excursions and maintaining very low distortion levels.
The high Qts of the compliance plus the added control of the servo will allow this woofer to behave as if it is in an enclosure even in an open baffle design. These woofers will produce a flat response to below 20Hz, with great control, good output levels, and with no enclosure. There simply is no better open baffle low frequency driver on the market.
Direct Servo amps are available right here.
See open baffle box plans for a W frame here.
See open baffle box plans for a H frame here.
Mechanical drawings are here.