user manual

Laney
44
Indroduction
The CA range of amplifiers use a new power output topology. This enables a design which has all the high
efficiency benefits of a class D type digital topology but without the usual draw backs of poor distortion and
difficult to control EMC problems. The CA design uses microprocessor-controlled high frequency switching of state
of the art output power FETs.
Most switching amplifiers work at frequencies of around 200kHz. The CA runs at varying rates depending on the
input signal from 600kHz to 1.2Mhz. This has many benefits both to efficiency and sonic performance.
The heart of the design uses thick film technology for high reliability and consistency. The power supply is a
conventional massive oversized toroidal design avoiding the problems of instant transient power delivery and
unreliability associated with many switch mode designs.
Due to the very high efficiency (typically 85-90%), noisy unreliable, fans are eliminated in favor of an aluminium
chassis and side mounted heat-sink extrusions.
The amplifier has the unique ability to look like a near perfect "audio modulated" power supply. This gives big
advantages when driving difficult loads where impedance's vary over the frequency spectrum the CA amplifier is
unaffected and drives the loads much more perfectly giving a dramatically improved performance to many
speaker systems.
The amplifiers also contain microprocessor controlled soft clipping and user switchable limiter* circuitry.
*(Factory fitted option only together with VCA control - Part Number LMT3000)
Speakon(TM) connectors are used for the outputs and a combination of electronically balanced XLR/Jack inputs.
The input gain is internally selectable by jumper links from +4dBu to 0dbu or to 26dB gain. (See later for
description) There are also input level controls on the fascia panel to attenuate down from the preset levels with
associated five band LED level displays.
The rear panel features bridge /mono mode switching and a signal earth lift.
The amplifier avoids the use of conventional unreliable fuses and uses automatically resetting devices for the
internal electronics and a front panel mounted manual re-settable overload cutout.
Protection circuitry covers over and under voltage operation, short /open circuit load conditions, DC Voltage and
excessive input signals.
Soft start circuitry is included to reduce switch on surges from the mains power. Automatic output muting is
included to avoid extraneous noise appearing at the speakers at turn on and turn off from the amplifier or other
units in the sound system.
Much work has been carried out to ensure EMC compliance is well within European and US standards for present
and future standards.
Three models are currently available:
CA600
CA1500
CA3000
Applications include, use as recording studio monitor and stereo broadcast amplifier, Professional PA amplifier,
and Esoteric hi-fi amplifier etc.
To gain maximum benefit from your amplifier please read and understand the instructions in this handbook. The
amplifiers have been created to meet any condition you may use them for. Enjoy.
CA MANUAL