Sealed 11.03 L
Follow the original construction and damping instructions.
Hertz / SUBWOOFER
Hertz HX 250 D — specifications and enclosures
Hertz HX 250 D: T/S parameters, mounting dimensions and manufacturer enclosure recommendations. Read the original PDF and load the driver into the 3D designer.
Sd calculated from manufacturer effective diameter D: π × (D/10)² / 4 cm². One-way linear Xmax is unverified; no excursion limit is assumed. Archived Hi-Energy model. Le is specified at 1 kHz. T/S values use series voice coils.
Manufacturer enclosure recommendations
Sealed 16.13 L
Follow the original construction and damping instructions.
Bass-reflex 15.15 L
Tuning Fb: 40 Hz.
The published volume is not confirmed as net air volume. Check the definition in the manual.
Published volume is not a verified net air volume. Use the original drawing and subtract occupied volumes before designing.
Documentation only — check the limitations before use.
PDF · page 4Bass-reflex 20.64 L
Tuning Fb: 38 Hz.
The published volume is not confirmed as net air volume. Check the definition in the manual.
Published volume is not a verified net air volume. Use the original drawing and subtract occupied volumes before designing.
Documentation only — check the limitations before use.
PDF · page 4Calculator parameters
| Fs | 34 Hz |
|---|---|
| Vas | 20.54 L |
| Qes | 0.39 |
| Qms | 6.8 |
| Re | 5.8 Ω |
| Sd | 346.36 cm² |
| Le | 7.27 mH |
| One-way linear Xmax | Not provided / unverified |
| Frame diameter | 26.8 cm |
| Mounting cutout | 23.4 cm |
| Mounting depth | 15.0 cm |
Additional manufacturer specifications
| Published Qts | 0.37 |
|---|---|
| Published Xmax (definition to verify) | 14 mm |
Data is for one subwoofer. Manufacturer recommendations are separate from CarBoxLab calculations. Net air volume excludes the driver, port and bracing; design dimensions are external. Loading a recommendation transfers the verified volume and tuning; confirm port geometry and construction separately.
Source documentation
Manufacturer technical documentation
Original manufacturer documents are not translated. Data reviewed: 2026-10-31.