JL Audio CR-1 crossover Active Subwoofer Crossover

Copied from the owners manual

PRODUCT OVERVIEW

CR-1 acts an
audiophile-grade “bridge”, seamlessly connecting a two-channel audio system
with a top-flight, powered subwoofer system. Powerful features and a pristine,
all-analog signal path make it a key component in optimizing an audio system’s
spatial and spectral performance. To minimize distortion and noise, CR-1
employs top-grade component parts in its all-analog audio circuitry: 1%
precision resistors, JFET-input audio-grade op-amps, polypropylene film-and-foil
capacitors and metallized-polypropylene film capacitors, to name just a few.
This attention to component quality makes CR-1 a worthy partner to the finest
audio preamplifiers and amplifiers.

CR-1’s input-output
design makes it equally adaptable to studio, mastering suite or audiophile,
two-channel playback environments. Inputs and outputs are provided for balanced
(XLR or 1/4-inch TRS) and unbalanced (RCA) sources. Independent buffering of
balanced and unbalanced outputs is employed, to reduce the likelihood of noise.
JL Audio’s differential input technology effectively rejects common-mode hum
and noise on the unbalanced inputs.

From the CR-1’s
stereo inputs, you can derive either a single “mono” (Left + Right) subwoofer
signal, or separate signals, for separate left and right subwoofers. A
front-panel switch allows you to select between these modes.

The CR-1’s crossover
functionality is built around two banks of high precision, low-pass and
high-pass Linkwitz-Riley filters. These can be set as 12 dB/octave (moderate
cutoff slope) or 24 dB/octave (steeper cutoff slope), via a front-panel switch.
For each filter pair, the cutoff frequency is fully variable from 30 Hz – 150
Hz via rotary controls. Behind these knobs, multiplying DACs with monolithic
ratio matching are employed to adjust the analog circuit’s filter frequencies.
This digitally–controlled, analog filter circuitry allows for high precision in
making frequency adjustments and facilitates precise matching between the left
and right channels for the ultimate in crossover fidelity and transparency. The
CR-1 offers 167 individual cutoff frequency choices between the 30 Hz and 150
Hz limits, in 0.70 Hz steps.

Another of CR-1’s
unique and powerful features is the ability to alter the damping behavior of
each filter bank. Properly used, the CR-1’s damping controls can improve the
acoustic summing through the crossover region, compensating for each speaker
system’s frequency response and the way they acoustically interact.

At the center of the
CR-1’s front panel, a convenient balance control permits fine level adjustment
of the subwoofer and satellite speakers, relative to one another. This is
useful for tweaking the sub/satellite balance to compensate for listening
conditions or program material, while always being able to easily return to the
reference setting. Each of the CR-1’s output channels can also be independently
muted via front-panel switches to aid in system setup and troubleshooting.

To facilitate sharing
your subwoofer(s) between a home theater system and a dedicated 2-channel
system, the CR-1 has a special bypass feature, accessible via a front-panel
switch. When this bypass is engaged, the CR-1 will pass signals connected to
its dedicated managed bass inputs, completely bypassing the CR- 1’s crossover
circuitry and level controls. This allows you to use your room’s subwoofers for
both 2-channel audio (via the CR-1’s bass management) and multichannel audio
(via your pre-pro or receiver’s bass management).

As you can see
from this brief introduction, the CR-1 packs a lot of useful technology and
functionality. Please read the following sections thoroughly to properly
connect and set up your CR-1.

Noted one small flaw on the top left of case. Shown in photo.