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Hertz PRO MP300.D4.3

Best box: 92.1 L bass reflex tuned to 23.1 Hz · F3 21.4 Hz

Predicted SPL response of the Hertz PRO MP300.D4.3 in the recommended 92.1 L bass reflex box versus the alternative — open it in the simulator Open and tweak this box live ↗

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⚠️ Engineering Notice for Builders

  • The textbook alignment (92.1 L at 22.0 Hz) would need a 45.7 cm port; the recommendation is retuned to 92.1 L at 23.1 Hz so the port can be built.

Recommended Bass Reflex (Vented)

PORT BUILDABLE
Net Box Volume (Vb) 92.1 Liters
Tuning Frequency (Fb) 23.1 Hz
F3 (-3 dB Cutoff) 21.4 Hz
F6 / F10 Extension 19.3 Hz / 17.2 Hz
Port Inner Diameter Ø 10.0 cm
Port Physical Length 40.8 cm
First Pipe Resonance 422.0 Hz
Estimated MOL @ F3 116.8 dB SPL
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Recommended Sealed (Acoustic Suspension)

MAX TRANSIENT DAMPING
Net Box Volume (Vb) 40.4 Liters
System Q (Qtc) 0.707 (Butterworth)
System Resonance (Fc) 39.9 Hz
F3 (-3 dB Cutoff) 39.9 Hz
F6 / F10 Extension 30.2 Hz / 22.9 Hz
Air Spring Linearity High (Zero port compression)
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Thiele/Small Parameters

Resonance (Fs) 24.0 Hz
Total Q (Qts) 0.42
Electrical Q (Qes) 0.452
Mechanical Q (Qms) 5.9
Equivalent Volume (Vas) 74.0 Liters
Diaphragm Area (Sd) 528.1 cm²
DC Resistance (Re) 1.9 Ω
Efficiency Bandwidth Product (EBP) 53.1
Linear Excursion (Xmax) 17.0 mm
Thermal Power (Pe) N/A W
Nominal Diameter 12.0"
Catalog Source Load Forge catalog (manufacturer datasheets and retailer listings)

Frequently Asked Questions

What is the recommended ported (bass reflex) box volume for Hertz PRO MP300.D4.3?

Load Forge's calculated alignment puts Hertz PRO MP300.D4.3 in a 92.1 liter vented enclosure tuned to 23.1 Hz, reaching an F3 cutoff of approximately 21.4 Hz.

Can Hertz PRO MP300.D4.3 be used in a sealed box?

Yes. In a sealed (acoustic suspension) enclosure of 40.4 liters with a Qtc of 0.707 (Butterworth), the system exhibits an F3 of 39.9 Hz.

What port dimensions should be used for Hertz PRO MP300.D4.3 to avoid port chuffing?

Sized from cone displacement (Sd × Xmax), a minimum port diameter of 10.0 cm with a length of 40.8 cm is suggested; check the port air velocity at your drive level in the Load Forge Studio.

Shareable Acoustic Card for Forums & Social Media

Embed this design card on DIYAudio, AVSForum, Reddit, or Facebook. It shows the calculated F3, MOL (when the power rating is published) and box parameters.

Hertz PRO MP300.D4.3 Enclosure Card
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