Cloud Electronics CX2300 - Manual (Page 3)

1 Introduction
The Cloud CX2300 3 Way Stereo Active Crossover has been designed without
compromise to operate with very low levels of noise and distortion as part of a high
quality professional sound system. A high degree of security is provided by using fixed
frequency plug-in filter cards together with a tamper proof cover for the front panel. Once
the unit has been correctly installed, no unauthorised adjustments can be made thus
maintaining system integrity and reliability.
Balanced audio connections are used throughout via Neutrik 3 pin XLR type connectors
with gold plated pins. We suggest that balanced interface connections are used wherever
possible, even for very short interconnections to take advantage of the common mode
rejection and freedom from earth loops when wired correctly.
The control layout is very simple and logical with each frequency band having its own
stereo controls for gain, phase invert and mute. In addition, a 20Hz high pass filter can be
switched in or out of the signal path. All these controls and switches, including the power
switch are protected by the security cover supplied with every unit.
Plug-in fixed frequency filter cards determine the frequency characteristics of the CX2300
and these can be specified from the list detailed in section 6.01. To change the frequency
of any filter card, refer to the component list in section 6.01 which gives details of
resistors which should be fitted to the filter card to achieve a particular frequency.
Experienced installers who are fully conversant with the Active filters and
Crossovers skip to section 3 for installation details.
2 Active Filters and Crossovers
2.01 Why use an Active Filter/Crossover ?
Virtually all high quality speaker systems whether domestic or professional use two or
three drivers to cover the whole of the audio spectrum with each driver specially designed
to reproduce a finite frequency range. In most low to medium power speaker systems, a
single full range power amplifier would be used to feed a passive crossover to filter the
signals to the two or three speakers within the full range enclosure. There are several
disadvantages when using full range amplification and passive filters; any differences in
driver efficiency have to be corrected by adding power resistors which is both wasteful
and reduces driver damping; High order passive filters with good attenuation levels are
expensive and inefficient; Any distortion present in the power amplifier is heard across the
whole audio spectrum.
A well designed fully active system will overcome all of the above problems, the sound
quality will be improved and the system will be much easier to set up. In a typical active
sound system, the bass, middle and treble regions would each have their own speaker
drive units which would be wired directly to separate power amplifiers. The bass amplifier
would be the most powerful, the amplifier used for the mid range would be around half the
power of the bass amplifier and the treble amplifier would be around half to two thirds the
power of that of the mid range amplifier.
The active filter/crossover would be used to separate the two or three frequency bands at
line level immediately before the signal connects to the power amplifiers.
Some active filters have adjustable crossover frequency controls which can be useful
when testing the system to determine the most satisfactory frequency but care must be
taken to ensure that any final setting is within the speaker manufacturers specifications.