RE Audio REX8 S4

8″ subwoofer · 4 Ω · 200 W RMS

Fs 19.8 HzQts 0.25Vas 1.48 ft³

Recommended box

For a sedan, one sub, 200 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 volume0.32 ft³ (9 L)
Qtc0.59
Fc47 Hz
F3 (−3 dB, no cabin gain)62 Hz
Example box (outside)10 5/8″ × 10 5/8″ × 8 5/8″
Open sealed box in designer

Ported

Net volume0.67 ft³ (19 L)
Tuning (Fb)35 Hz
Portround port Ø2 1/2″, 14 3/8″ long
Port velocity at 200 W130 ft/s
F3 (−3 dB, no cabin gain)33 Hz
Example box (outside)18 9/16″ × 15 3/4″ × 6 7/8″
Open ported box in designer
2030405060801001502006066727884HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs19.8 Hz
Qts0.25
Qes0.259
Qms5.3
Vas1.48 ft³
Re3.46 Ω
Sd34.4 in²
Xmax≈ 0.39″
Mms107 g calc.
BL13.3 T·m calc.
EBP76 — sealed or ported calc.
Sensitivity, 1 W / 1 m83 dB calc.

General

Size8″
Voice coils4 Ω
RMS power200 W

Mounting dimensions

Ø8 11/16″cutout Ø7 5/16″mounting depth 4 1/2″magnet Ø≈ 4 3/4″
Cutout diameter7 5/16″
Mounting depth4 1/2″
Overall diameter8 11/16″

“≈” 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