Reflex Optimized
Beyma Products - Beyma - Professional Speaker Manufacturer since 1969
Complete Thiele/Small parameters, optimized ported (bass reflex) and sealed enclosure designs, F3/F6/F10 cutoffs, and vent turbulence analysis calculated by Load Forge.
⚠️ Engineering Notice for Builders
- Large enclosure volume (131.1 L) requires extensive internal matrix bracing to prevent panel resonance.
Recommended Bass Reflex (Vented)
OPTIMIZED EXTENSION| Net Box Volume (Vb) | 131.1 Liters |
| Tuning Frequency (Fb) | 38.4 Hz |
| F3 (-3 dB Cutoff) | 39.9 Hz |
| F6 / F10 Extension | 35.6 Hz / 31.3 Hz |
| Port Inner Diameter | Ø 20.8 cm |
| Port Physical Length | 37.9 cm |
| First Pipe Resonance | 454.0 Hz |
| Estimated MOL @ F3 | 124.3 dB SPL |
Recommended Sealed (Acoustic Suspension)
MAX TRANSIENT DAMPING| Net Box Volume (Vb) | 61.7 Liters |
| System Q (Qtc) | 0.707 (Butterworth Q=0.707) |
| System Resonance (Fc) | 69.9 Hz |
| F3 (-3 dB Cutoff) | 70.9 Hz |
| F6 / F10 Extension | 51.4 Hz / 37.7 Hz |
| Air Spring Linearity | High (Zero port compression) |
Verified Thiele/Small Parameters
| Resonance (Fs) | 30.0 Hz |
| Total Q (Qts) | 0.29 |
| Electrical Q (Qes) | 0.3 |
| Mechanical Q (Qms) | 8.6 |
| Equivalent Volume (Vas) | 305.0 Liters |
| Diaphragm Area (Sd) | 1734.0 cm² |
| DC Resistance (Re) | 5.4 Ω |
| Efficiency Bandwidth Product (EBP) | 100.0 |
| Linear Excursion (Xmax) | 14.0 mm |
| Thermal Power (Pe) | 1600.0 W |
| Nominal Diameter | 21.0" |
| Catalog Source | Manufacturer Official Datasheet |
Shareable Acoustic Card for Forums & Social Media
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