Eminence EMILEG121
Best box: 31.2 L sealed · Fc 141.4 Hz · F3 118.7 Hz
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Comparable 12.0" Drivers
Drivers with similar piston area, resonance and Qts — useful alternatives when the Eminence EMILEG121 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
- Limited linear excursion (Xmax: 0.8 mm); set a high-pass subsonic filter at 25–30 Hz when driven with high power.
Textbook Bass Reflex — not recommended (5.4 dB bass hump)
PORT BUILDABLE| Net Box Volume (Vb) | 25.0 Liters |
| Tuning Frequency (Fb) | 85.0 Hz |
| F3 (-3 dB Cutoff) | 139.8 Hz |
| F6 / F10 Extension | 131.1 Hz / 118.4 Hz |
| Port Inner Diameter | Ø 10.0 cm |
| Port Physical Length | 5.9 cm |
| First Pipe Resonance | 2923.0 Hz |
| Estimated MOL @ F3 | 113.3 dB SPL |
Sealed (Acoustic Suspension) — compromise
SUITS INFINITE / OPEN BAFFLEWith Qts 4.0 a Butterworth (Qtc 0.707) box would be many times Vas. A box equal to Vas reaches Qtc 5.657; for a flat response this driver is better used on an infinite (IB) or open baffle.
| Net Box Volume (Vb) | 31.2 Liters |
| System Q (Qtc) | 5.657 (above Butterworth: Qtc cannot fall below Qts (4.00)) |
| System Resonance (Fc) | 141.4 Hz |
| F3 (-3 dB Cutoff) | 118.7 Hz |
| F6 / F10 Extension | 111.8 Hz / 102.1 Hz |
| Air Spring Linearity | High (Zero port compression) |
Thiele/Small Parameters
| Resonance (Fs) | 100.0 Hz |
| Total Q (Qts) | 4.0 |
| Electrical Q (Qes) | 4.101 |
| Mechanical Q (Qms) | 163.0 |
| Equivalent Volume (Vas) | 31.2 Liters |
| Diaphragm Area (Sd) | 506.7 cm² |
| DC Resistance (Re) | 121.0 Ω |
| Efficiency Bandwidth Product (EBP) | 24.4 |
| Linear Excursion (Xmax) | 0.8 mm |
| Thermal Power (Pe) | 150.0 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 Eminence EMILEG121?
A simple ported box is not recommended for Eminence EMILEG121: the textbook alignment (25.0 liters tuned to 85.0 Hz) needs a 5.9 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 Eminence EMILEG121 be used in a sealed box?
Yes. In a sealed (acoustic suspension) enclosure of 31.2 liters with a Qtc of 5.657 (above Butterworth: Qtc cannot fall below Qts (4.00)), the system exhibits an F3 of 118.7 Hz.
What port dimensions should be used for Eminence EMILEG121 to avoid port chuffing?
A straight 10.0 cm port would need 5.9 cm of length, which does not fit a practical cabinet. Use a passive radiator or a folded/3D duct instead of a straight tube.
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