Martin Audio Wavefront W8CT, Инструкция по применению

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See MA4.2 Power Amplifier User's Guide for detailed operating instructions.
Cooling System
The Martin Audio MA4.2 amplifier runs very cool due to a special patented copper
cooling system. The amplifier’s bi-polar output devices are mounted directly onto a
copper heat sink (copper conducts heat twice as efficiently as aluminium) and
maximum heat dissipation is achieved by turbulent airflow over the heatsink’s
geometric fins.
The MA4.2 amplifier features two proportional speed cooling fans which take in air
from the front of the amplifier and exhaust from the rear. A horizontal pressure
chamber between the heatsink and the cooling fans ensures that there is little
difference in the operating temperatures of each output device. In contrast, a
conventional tunnel design can result in a temperature variance of up to 40° between
output devices.
Switch Mode Power Supply
The MA4.2’s switch mode power supply (SMPS) is the modern solution to the
problems of size and weight. Switch mode power supplies are not new - they are
found in computers and televisions. However, the demands of high power audio are
very different to these applications. The MA4.2 overcomes the size and weight
constraints of conventional power supplies whilst at the same time avoiding the
pitfalls of typical switch mode designs.
The low output impedance of the SMPS means that rail voltages do not sag under
heavy load conditions. Additionally, the rail capacitors are being recharged at a much
faster rate than those in a conventional power supply. The result is an exceptional fast
transient low frequency performance at all power levels.
Efficiency is also maximised. With much smaller transformers than a conventional
supply, there is much less loss due to transformer resistance and much less power
wasted as heat in the power supply.
Regulation of the SMPS means that the power amplifier will produce the same power
output, even if the AC line voltage drops by 20%.
Minimum Load Switches (MLS™)
Because the SMPS is regulated, the maximum power available for the output stages
can be adjusted without increased heat dissipation or efficiency loss. This allows the
user to match the output power with the loudspeaker impedance.
All material © 2007. Martin Audio Ltd. Subject to change without notice.