Subwoofer Crossover/Controller

SBX Subwoofer Crossover/Controller

A new generation of high performance, high output super subwoofers for control room applications has been made possible by the development of the single rackspace SBX Subwoofer Crossover/Controller. Designed for ease of room alignment and absolute driver control and protection, while delivering true audiophile sound (.001 % THD, S/N > 105 dB and a 180kHz highpass bandwidth), the SBX provides seamless integration of any combination of our subwoofers, wide-range monitors and studio amplifiers. Deadly quiet and absolutely transparent in operation, the pure analog SBX is a no-compromise solution to the problems that often plague subwoofer installations. It is, perhaps, the only way to integrate monitor and sub with their environment in a fashion that eliminates the sense of "seperate" subwoofer and guarantees a pristine highpass signal. With the adjustable lowpass Q correcting for power response at the crossover point and fully sweepable phase control for system alignment compensating for room and/or baffle gain, the SBX can literally "move" the sub back from the monitoring position thru careful adjustment of these highly interactive controls. Internal parameters are set via drop-in boards tailored specifically to one of our subwoofers. For user-specified custom installations, "designer" boards may be commissioned.

Engage / Bypass
Useful during both setup and normal operation, this feature acts as a "straight wire" in the bypass position, removing the subwoofer from the system, and transparently adds in all features and settings when engaged.

Lowpass Frequency
Adjusts the 4th order lowpass frequency from 35 Hz to 200 Hz.

Lowpass Q
Working in conjunction with the Lowpass Frequency control, the Q adjusts "damping" of the crossover corner frequency, optimizing power response at the transition point.

This control uses a potentiometer and an all pass filter to scale the subwoofer's phase from 0 to 180 degrees. This can be one of the most useful tools in blending a sub into any system.

This switch simply inverts the signal polarity from 0 to 180 degrees. In combination with the Phase control it enables the user to find, by ear, the approximate phase setting that is correct for any given system. With measurement gear such as an RTA, the crossover point can be fine tuned to perfection.

Shelf Frequency
Setting the frequency at which the shelf is centered, this control is used in conjunction with the LF Shelf control to compensate for room gain and baffle reinforcement effect, allowing for greater latitude in subwoofer placement within the environment.

LF Shelf
This control applies the amount of boost or cut around the shelf frequency.

Lowpass Gain
A subwoofer volume control allowing for precise level matching with main speakers.

LF Limiting
This potentiometer resides inside the chassis and is set according to the gain structure of the amp driving the subwoofer. Adjusted either at the factory or by an approved field technician, it provides inaudible voltage limiting for situations where the system may be driven to potentialy damaging levels. When dialed completely clockwise, there is no limiting.

The SBX is provided with both XLR and RCA inputs and outputs to accommodate most systems. When fitted with optional Jensen input transformers, only balanced XLR inputs are available with both types of outputs active.

Jensen Tranformer Input Option
Certainly the best signal transformers available, the Jensens offer total transparency, maintaining the system's 3dB points of 2Hz and 180kHz, for those seeking the highest level of sound quality and complete isolation.

Four Layer Circuit Board
A rarity in audio electronics, the SBX circuit board is comprised of 4 independent layers of copper providing the shortest signal paths for ultimate clarity and performance. Another huge advantage is that one of the layers serves as a ground plane which provides excellent shielding for the sensitive small signals traveling on the board.

Subwoofers have always presented challenges in music systems due in large part to the inadequate crossovers and filters that control them. Often no more than an afterthought, they are frequently blamed for taking the "musicality" out of a system. While the benefits of adding a subwoofer to any system are great, many serious listeners and professionals avoid them in favor of preserving the merits of their main speakers. Now there is a true solution for anyone who wants all of the benefits of adding a subwoofer with none of the drawbacks.

SBX Subwoofer Crossover/Controller

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