American Bass KING-1211
Best box: 10.9 L sealed · Fc 59.4 Hz · F3 58.3 Hz
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Comparable 12.0" Drivers
Drivers with similar piston area, resonance and Qts — useful alternatives when the American Bass KING-1211 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
- Straight vent would be 470.9 cm long: not physically buildable as a simple tube. Use a passive radiator, a folded slot port or model a 3D folded duct in Load Forge Studio.
Textbook Bass Reflex — not recommended
PORT NOT BUILDABLE| Net Box Volume (Vb) | 9.8 Liters |
| Tuning Frequency (Fb) | 33.5 Hz |
| F3 (-3 dB Cutoff) | 42.6 Hz |
| F6 / F10 Extension | 30.5 Hz / 25.6 Hz |
| Port Inner Diameter | Ø 15.0 cm |
| Port Physical Length | 470.9 cm |
| First Pipe Resonance | 37.0 Hz |
| Estimated MOL @ F3 | 117.9 dB SPL |
Recommended Sealed (Acoustic Suspension)
MAX TRANSIENT DAMPING| Net Box Volume (Vb) | 10.9 Liters |
| System Q (Qtc) | 0.707 (Butterworth) |
| System Resonance (Fc) | 59.4 Hz |
| F3 (-3 dB Cutoff) | 58.3 Hz |
| F6 / F10 Extension | 44.7 Hz / 34.0 Hz |
| Air Spring Linearity | High (Zero port compression) |
Thiele/Small Parameters
| Resonance (Fs) | 47.3 Hz |
| Total Q (Qts) | 0.56 |
| Electrical Q (Qes) | 0.626 |
| Mechanical Q (Qms) | 5.33 |
| Equivalent Volume (Vas) | 6.5 Liters |
| Diaphragm Area (Sd) | 498.0 cm² |
| DC Resistance (Re) | 1.6 Ω |
| Efficiency Bandwidth Product (EBP) | 75.6 |
| Linear Excursion (Xmax) | 22.5 mm |
| Thermal Power (Pe) | 6500.0 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 American Bass KING-1211?
A simple ported box is not recommended for American Bass KING-1211: the textbook alignment (9.8 liters tuned to 33.5 Hz) needs a 470.9 cm port, and no nearby retune stays buildable without a bass hump. A sealed box, a passive radiator or a folded duct is the practical choice.
Can American Bass KING-1211 be used in a sealed box?
Yes. In a sealed (acoustic suspension) enclosure of 10.9 liters with a Qtc of 0.707 (Butterworth), the system exhibits an F3 of 58.3 Hz.
What port dimensions should be used for American Bass KING-1211 to avoid port chuffing?
A straight 15.0 cm port would need 470.9 cm of length, which does not fit a practical cabinet. Use a passive radiator or a folded/3D duct instead of a straight tube.
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.
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