Compact, highly versatile enclosure
12"LF + 12" coaxial with 2.5" HF
70H x 50V degree directivity, optional 90x55 and 120x60
2-way biamp enclosure, passive MF/HF
LF extension with M118, M218, SB115i


The RMS-Acoustics C12XL is a coaxial loudspeaker system designed to deliver superior output levels that exceed conventional premium 2-way systems, with superior pattern control, directional consistency and a precise transient response that only a coaxial loudspeaker can provide. This is accomplished by the addition of a second 12” low frequency loudspeaker, mounted in a separate, optimally sized and vented enclosure within the same cabinet. The result is a true full range loudspeaker in a versatile and highly compact size.

The C12XL features an advanced high frequency waveguide that also acts as a phasing plug for the 12” cone loudspeaker. The horn is quite large for its size, yielding consistent pattern control and a low crossover point. The phasing plug improves the response of the cone loudspeaker, minimizing the equalization and phase correction needed, thus aiding the transition between sources over the crossover band.

The enclosure of the C12XL features a 40° trapezoidal angle to allow close mountings to walls or ceilings, with little to no impact on sightlines. Its tailorable pattern control, easy mounting and array ability with RMS-Acoustics array brackets allow a simple, cost effective method to tailor a sound reinforcement solution to achieve the best possible acoustical results in almost any space. Optimized nonlinear venting improves the low frequency impedance compared to conventional enclosures, while maintaining better mechanical cone control when low frequency extension is required. The result is tight, punchy bass and a low frequency extension not achievable by traditional 2-way enclosures.

The C12XL cabinet is crafted from premium multi-ply birch with a finely textured polyurethane finish that is impact and UV resistant. A powder-coated, punched and laser cut steel grille protects the cabinet internal from the elements. Full weather protection and custom color finishes are also available. The weatherized option provides and IP54 rating.

The optimum processed amplifier solution for the RMS-Acoustics C12XL are the RMS-ACOUSTICS series of processed and network managed amplifiers, also the Linea Research C and M series amplifiers, with proprietary presets provided by RMS-ACOUSTICS.


Frequency Range (-10dB) ^1 38 Hz - 20 kHz
Frequency Response (+/-3dB) 50 Hz - 18 kHz
System Sensitivity (1w, 1m)^2 101dB Measured on LF band, average SPL over 300 to 2 kHz region. HF Sensitivity significantly higher
Maximum SPL Continuous (1m) 131dB
Maximum SPL Peak (1m) 137dB
Long Term Power Rating (AES)^4 LF


1000W (2800W Peak), 2 hr, 700W 100Hr

700W   (2800W Peak), 2 hr, 500W 100Hr

Long Term Power Rating (IEC)^3 LF


700W, 2800W (Continuous, Peak)

700W, 2800W (Continuous, Peak)

Nominal Coverage Pattern 120° x 60°

70° x 50°

90° x 55°

90° x 80°           All are rotatable in 45° angular increments

System Crossover 1200 Hz Proprietary FIR overlay, 300 Hz MF/HF electronic IIR w/ all pass and FIR phase correction
Transducer SPKR-12-0007







LF, Passive MF/HF

LF Driver - 12” cone loudspeaker with 3.5” voice coil, shorting ring and high performance convective cooling technology


MF/HF Coaxial Driver - 12” Neodymium loudspeaker with 3” LF voice coil, 2.5” HF voice coil


HF Driver Replacement - 1.4” exit Neodymium compression driver with 2.5” voice coil, shorting ring and advanced phase plug geometry


Impedance - 8 Ohm,  8 Ohm

Input Connectors Dual Neutrik NL4MP Connectors
Enclosure Materials 15 and 18mm Birch Hardwood Ply 1.3mm layers
Grille Materials Cold Rolled steel, Epoxy powder coat, Acoustically transparent black foam backing
Finishes Black finish (Standard) Polyurethane textured spray
Additional Finishes available - See Options Below
Suspension and Mounting Proprietary internal, captive rigging, M10 mounting locations, Rear 4 Bolt pattern
Dimensions 14.0” W x 14” D x 31” H  (356 mm x 356 mm x 788 mm)
Weight 75 Lb (31.4 kg) Net 84 Lb (38.2 kg) Shipping
Finish Options -X1 (Weatherized), -X2 (Weatherized), -W (White), -C (RAL Custom Color) Upcharge applies
Optional Accessories & Rigging Hardware C12XL-HU Horizontal U Bracket specific to C12XL
WM-L RMS-Acoustics wall mount large with lateral orientation and vertical tilt
C12-AF Two box array frame for C12/C12XL
Free field, semi anechoic conditions.  To compare with half space measurements, add 6dB to maximum output specifications.
1. Full Space, 4pi conditions
2. Measured Maximum SPL, based on power compression observation of 3dB
3. IEC Shaped pink noise with 6dB Crest Factor
4. AES Standard AES2-2012, one decade pink noise with 6dB Crest factor within device’s applicable operating band, free air. Standard AES 2 hr rating are specific for low frequency transducers.