URAL Patriot 8 (2+2)
8″ subwoofer · dual 2 Ω · 750 W RMS
Fs 41.9 HzQts 0.41Vas 0.18 ft³Xmax 0.79″
Recommended box
For a sedan, one sub, 750 W. It’s the same math as the designer’s step-by-step mode, where you can fit the box to your space, vehicle and amp and get plans, a cut sheet and DXF.
Sealed
| Net volume | 0.28 ft³ (8 L) |
|---|---|
| Qtc | 0.53 |
| Fc | 54 Hz |
| F3 (−3 dB, no cabin gain) | 80 Hz |
| Example box (outside) | 10 5/8″ × 10 5/8″ × 7 7/8″ |
Ported
| Net volume | 0.57 ft³ (16 L) |
|---|---|
| Tuning (Fb) | 30 Hz |
| Port | slot 1 15/16 × 14 5/16″, 143 7/8″ long |
| Port velocity at 750 W | 40 ft/s |
| F3 (−3 dB, no cabin gain) | 28 Hz |
| Example box (outside) | 31 1/2″ × 15 3/4″ × 14 5/16″ |
The volume and tuning are the recommendation, but the port doesn’t fit this example box. Size the box and port in the designer.
Open ported box in designerThiele/Small parameters
| Fs | 41.9 Hz |
|---|---|
| Qts | 0.41 |
| Qes | 0.46 |
| Qms | 3.76 |
| Vas | 0.18 ft³ |
| Re (one coil) | ≈ 1.7 Ω |
| Sd | 29.2 in² |
| Xmax | 0.79″ |
| Vd | 23 in³ calc. |
| Mms | 140 g calc. |
| BL | 11.7 T·m calc. |
| EBP | 91 — sealed or ported calc. |
| Sensitivity, 1 W / 1 m | 81.2 dB calc. |
General
| Size | 8″ |
|---|---|
| Voice coils | dual 2 Ω |
| RMS power | 750 W |
Mounting dimensions
| Cutout diameter | 7 1/2″ |
|---|---|
| Mounting depth | 4 15/16″ |
| Overall diameter | 8 7/16″ |
| Magnet diameter | 6 1/8″ |
Cone area (Sd) calculated from Fs, Vas and Mms: 29.2 in².
“≈” means the value isn’t in the spec sheet and a typical value for the size is used; “calc.” means it’s calculated from the published parameters. Check the manufacturer’s spec sheet before you build.