Dayton Audio UM8-22

8″ subwoofer · dual 2 Ω · 300 W RMS

Fs 31.6 HzQts 0.58Vas 0.75 ft³Xmax 0.63″

Recommended box

For a sedan, one sub, 300 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 volume0.74 ft³ (21 L)
Qtc0.82
Fc45 Hz
F3 (−3 dB, no cabin gain)41 Hz
Example box (outside)10 5/8″ × 10 5/8″ × 17 1/4″
Open sealed box in designer

Ported

Net volume1.27 ft³ (36 L)
Tuning (Fb)31 Hz
Port2 round ports Ø2 1/2″, 20″ long
Port velocity at 300 W90 ft/s
F3 (−3 dB, no cabin gain)27 Hz
Example box (outside)31 1/2″ × 15 3/4″ × 7 5/16″
Open ported box in designer
2030405060801001502006066727884HzdB
Sealed Ported · SPL in dB at 1 W / 1 m, no cabin gain

Thiele/Small parameters

Fs31.6 Hz
Qts0.58
Qes0.75
Qms2.51
Vas0.75 ft³
Re (one coil)2.1 Ω
Sd32.7 in²
Xmax0.63″
Vd20.6 in³ calc.
Mms75 g calc.
BL6.5 T·m calc.
EBP42 — suits sealed calc.
Sensitivity, 1 W / 1 m81.5 dB calc.

General

Size8″
Voice coilsdual 2 Ω
RMS power300 W

Mounting dimensions

Ø8 1/4″cutout Ø7 7/16″mounting depth 4 3/4″magnet Ø≈ 4 13/16″
Cutout diameter7 7/16″
Mounting depth4 3/4″
Overall diameter8 1/4″

“≈” 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 Dayton Audio 8″ models