Cadence S1W8D4.v2
8″ subwoofer · dual 4 Ω · 250 W RMS
Fs 38.5 HzQts 0.52Vas 0.89 ft³Xmax 0.52″
Recommended box
For a sedan, one sub, 250 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 | 0.64 ft³ (18 L) |
|---|---|
| Qtc | 0.81 |
| Fc | 60 Hz |
| F3 (−3 dB, no cabin gain) | 56 Hz |
| Example box (outside) | 10 5/8″ × 10 5/8″ × 15 1/16″ |
Ported
| Net volume | 1.31 ft³ (37 L) |
|---|---|
| Tuning (Fb) | 38 Hz |
| Port | slot 1 9/16 × 14 5/16″, 28 1/16″ long |
| Port velocity at 250 W | 45 ft/s |
| F3 (−3 dB, no cabin gain) | 34 Hz |
| Example box (outside) | 31 1/2″ × 15 3/4″ × 8 13/16″ |
Thiele/Small parameters
| Fs | 38.5 Hz |
|---|---|
| Qts | 0.52 |
| Qes | 0.569 |
| Qms | 6 |
| Vas | 0.89 ft³ |
| Re (one coil) | ≈ 3.4 Ω |
| Sd | ≈ 33.3 in² |
| Xmax | 0.52″ |
| EBP | 68 — sealed or ported calc. |
| Sensitivity, 1 W / 1 m | 86 dB calc. |
General
| Size | 8″ |
|---|---|
| Voice coils | dual 4 Ω |
| RMS power | 250 W |
Mounting dimensions
| Cutout diameter | 7 5/16″ |
|---|---|
| Mounting depth | 5 3/16″ |
Only Qts is published — Qms assumed to be 6 and Qes calculated (barely affects box design).
“≈” 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.
Data sources
Other Cadence 8″ models
- Cadence S2W8D2 8″ · dual 2 Ω
- Cadence S2W8D4 8″ · dual 4 Ω