Kartesian Cox120_vHP
Best box: 2.1 L bass reflex tuned to 79.5 Hz · F3 77.6 Hz
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Comparable 4.0" Drivers
Drivers with similar piston area, resonance and Qts — useful alternatives when the Kartesian Cox120_vHP does not fit your target box volume or tuning. Each entry links to its full enclosure design and Thiele/Small parameters.
⚠️ Engineering Notice for Builders
- The textbook alignment (2.1 L at 75.7 Hz) would need a 45.3 cm port; the recommendation is retuned to 2.1 L at 79.5 Hz so the port can be built.
- Xmax is not published, so the port size is an empirical estimate (area ≥ 12 in² per ft³ of net volume, minimum by driver size), not a displacement calculation. Check air velocity in Load Forge Studio.
Recommended Bass Reflex (Vented)
PORT BUILDABLE| Net Box Volume (Vb) | 2.1 Liters |
| Tuning Frequency (Fb) | 79.5 Hz |
| F3 (-3 dB Cutoff) | 77.6 Hz |
| F6 / F10 Extension | 69.2 Hz / 60.8 Hz |
| Port Inner Diameter ESTIMATED | Ø 5.0 cm |
| Port Physical Length | 40.8 cm |
| First Pipe Resonance | 422.0 Hz |
Recommended Sealed (Acoustic Suspension)
MAX TRANSIENT DAMPING| Net Box Volume (Vb) | 0.93 Liters |
| System Q (Qtc) | 0.707 (Butterworth) |
| System Resonance (Fc) | 139.9 Hz |
| F3 (-3 dB Cutoff) | 137.4 Hz |
| F6 / F10 Extension | 104.4 Hz / 78.9 Hz |
| Air Spring Linearity | High (Zero port compression) |
Thiele/Small Parameters
| Resonance (Fs) | 68.1 Hz |
| Total Q (Qts) | 0.339 |
| Electrical Q (Qes) | 0.369 |
| Mechanical Q (Qms) | 4.2 |
| Equivalent Volume (Vas) | 3.1 Liters |
| Diaphragm Area (Sd) | 47.8 cm² |
| DC Resistance (Re) | 5.3 Ω |
| Efficiency Bandwidth Product (EBP) | 184.6 |
| Linear Excursion (Xmax) | N/A mm |
| Thermal Power (Pe) | N/A W |
| Nominal Diameter | 4.0" |
| Catalog Source | Load Forge catalog (manufacturer datasheets and retailer listings) |
Frequently Asked Questions
What is the recommended ported (bass reflex) box volume for Kartesian Cox120_vHP?
Load Forge's calculated alignment puts Kartesian Cox120_vHP in a 2.1 liter vented enclosure tuned to 79.5 Hz, reaching an F3 cutoff of approximately 77.6 Hz.
Can Kartesian Cox120_vHP be used in a sealed box?
Yes. In a sealed (acoustic suspension) enclosure of 0.93 liters with a Qtc of 0.707 (Butterworth), the system exhibits an F3 of 137.4 Hz.
What port dimensions should be used for Kartesian Cox120_vHP to avoid port chuffing?
Xmax is not published for Kartesian Cox120_vHP, so the port is an empirical estimate: a 5.0 cm diameter with a length of 40.8 cm (area at least 12 in² per ft³ of net volume). Check the air velocity at your power level in Load Forge Studio.
Shareable Acoustic Card for Forums & Social Media
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