The THX® certified Monolith SUB15 subwoofer delivers deep bass with low distortion. Dropping below 16Hz, the Monolith SUB15 unleashes significant volume with the ability to convey and articulate the subtle nuances of your music or movies.
THX Ultra Certified
THX engineers have performed hundreds of different tests to ensure the best possible audio performance. These tests ensure that the speaker can reach high volumes without creating audible distortion or artifacts. THX Certified Ultra products are intended for large rooms, up to 85m³ in volume.
The 15" (38.1cm) driver used was developed with a design focused on achieving high efficiency, high precision, good dynamics and linearity, while minimizing distortion. It is housed in an HDF cabinet with massive internal bracing. It is equipped with three vents, which can be filled with foam plugs if necessary for a completely sealed operation.
The 1000W integrated amplifier is built around a Texas Instruments 48bit architecture (with 28bit filter coefficients) and DSP. Each amplifier's transfer function, output power limiting and thermal protection are monitored to the millisecond. The high-performance Class D amplifier modules are based on a proven topology that has been continuously improved over the last 4 years. The amplifier has a large power reserve for accurate and deep bass, whether for a home theater or HiFi system.
The subwoofer in detail
Body and internal reinforcements : The use of HDF (High Density Fiberboard) instead of MDF results in a sonically inert cabinet. The internal bracing was intelligently placed to increase the overall strength of the cabinet and limit unwanted panel vibration, which could cause sound discoloration and distortion. The strength of the cabinet and the bracing combine to ensure massive bass, not resonance.
Vents and grids : The Monolith SUB15 uses three 88.5mm vents with internal and external flares. These multiple ports are used to ensure high sound pressure at low frequencies (fb=21Hz). The double flares are used to reduce asymmetric distortion. The vents can also be plugged with the supplied plugs. The "floating" grille is made from rigid MDF and is offset from the cabinet to maximize airflow from the woofer and vents.
Every part of the driver has been developed to deliver high output, low distortion and accurate bass. Its unique diaphragm combines paper and fiberglass, taking advantage of the benefits of each material for high durability and impressive linear excursion capability. The result is a diaphragm capable of achieving optimal movement at any frequency it can be asked to produce.
1. Lower suspension : Finite Element Analysis (FEA) modeling and Klippel laser-based optimizations were used to design a diaphragm capable of impressive linear excursion. The lower and upper suspensions are designed in conjunction with the engine structure. The lower suspension is essential to maintain very low distortion levels at high excursions, which is essential to achieve high SPLs at low frequencies.
2. Spider and air vents : The spider is made from several layers of NOMEX® and installed by hand, ensuring low mass but high strength and durability. The advantages of the air vents are twofold: on the one hand, they allow air flow to effectively cool the voice coil, and on the other hand, they reduce asymmetrical compliance due to air compression under the diaphragm and the spider, which would manifest itself in unwanted distortions.
3. Membrane suspension : Again, FEA modeling and Klippel optimization are used to create the large membrane suspension. This suspension is made from a unique formulation of NBR (Nitrile Butadiene Rubber). This material was developed after months of prototyping to ensure the highest levels of excursion without sacrificing linearity or distortion.
4. Motor structure : The motor is made of CNC machined low carbon steel in an assembly to concentrate the magnetic flux. Rings are used to cancel eddy currents to further stabilize the magnetic flux and greatly reduce distortion. Precision winding, made of aluminum (which has lower thermal compression than copper) allows the coil to remain cool. The design of the motor and suspension is extremely important to ensure perfect control of the speaker's movement over a very wide range of input signals, for a high output level and minimal distortion.