Eminence Delta-12A 8 Ohm

Eminence Delta-12A 8 Ohm — Pro-Grade 12" Mid-Bass / Woofer Driver

The Eminence Delta-12A 8 Ohm is a 12-inch cone driver from the American Standard Series, engineered for high-output mid-bass or woofer use (with high-pass filter) in vented enclosures. It finds its place in lead and bass guitar combos, keyboard amplification, club sound systems, and stage monitors. Eminence manufactures the Delta-12A in Kentucky, pairing a 400 W RMS power rating with 98.3 dB sensitivity to give system builders a robust, articulate base for two-way PA cabinets or replacement-driver projects.

What Makes the Delta-12A Stand Out

At the core is a vented pole piece and a 2.5-inch (63.5 mm) voice coil wound with polyamide-imide coated aluminum wire on a Kapton® polyimide former. This design delivers the thermal margin required for continuous, high-power use. The pressed-steel basket, paper cone, and double-roll cloth surround create a field-serviceable assembly, making this model a long-standing reference for replacement woofers in popular cabinets like the JBL JRX212.

Power Handling & Sensitivity — Optimized for Loud Spaces

Combining power handling and sensitivity determines the SPL ceiling before amplifier headroom is exhausted. Delta-12A is rated for 400 W continuous (RMS) and 800 W program, with 98.3 dB measured sensitivity at 2.83 V / 1 m—allowing even modest amplifiers to achieve club-ready output.

• Power Handling (RMS): 400 W — supports everyday program material without thermal stress.
• For transient peaks, program power handling rises to 800 W.
• Sensitivity: 98.3 dB (2.83 V / 1 m) — efficient output eases amplifier demand.

Frequency Response & Thiele-Small Parameters — Cabinet Tuning Details

Frequency response and Thiele-Small parameters guide box designers in predicting driver performance. Eminence lists a 54–5,000 Hz usable range, resonant frequency (Fs) of 55 Hz, and total Q (Qts) of 0.43—ideal for a vented cabinet around 3.1 ft³ for F3 near 53 Hz, or a sealed 1 ft³ design for punchier, higher F3 response.

• Frequency Response: 54–5,000 Hz — handles low, midbass, and midrange roles in two-way systems.
• Resonant Frequency (Fs): 55 Hz — defines the low-frequency boundary before cabinet tuning dominates.
• For enclosure alignment, Vas / Qts: 81.3 L / 0.43 is essential data.
• Xmax: ±2.4 mm — marks the linear excursion threshold prior to increased distortion.

Construction & Mounting — Road-Ready Build

Material selection and mounting geometry determine resilience during touring and recone operations. A paper cone, double-roll cloth surround, ferrite magnet, and pressed-steel basket combine with dimensions of 305.6 mm outer diameter, 281.2 mm baffle cutout, and 135.9 mm mounting depth. These specs match standard 12-inch cabinet cutouts.

• Voice Coil: 2.5" (63.5 mm) aluminum wire on Kapton® polyimide former — dissipates heat during sustained output.
• Cone / Surround: Paper cone with double-roll cloth surround — delivers classic Eminence mid articulation.
• Durability and field replacement are ensured by a ferrite magnet in a pressed-steel basket.
• Mounting: 305.6 mm OD, 281.2 mm cutout, 135.9 mm depth, 8 mounting holes — fits standard 12" cabinets.
• Weight: ~5.2 kg — well-suited for both portable and installed applications.