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POWER CONSUMPTION
There are three ways to define the power/current consumption of the
amplifier.
First, the peak current draw at full sine wave power output. Under this
condition the amplifier could thermally limit or blow the mains fuse, and is
an unrealistic ‘normal’ use condition. To design a mains distribution system
based on the current draw at full power would result in an over specified
system. No music programme material requires the full steady state
continuous power of an amplifier; this operating condition is only valid for
amplifier bench testing.
Second, the maximum expected average current under worst case
conditions, which corresponds to 1/3 of full power according to the FTC
standard. At this level the program material will be in a state of constant clip
and is the highest power level that can be obtained without completely
obliterating the program content.
Lastly, the "normal operating power", as defined by EN60065 as a
measurement level for approval and testing to this standard. The normal
operating power is measured using pink noise, with an average output
power equal to
1
/
8
of full power. The
1
/
8
power is the maximum volume music
can be replayed without continuous amplifier clipping, corresponding to a
headroom of 9dB's, which is very low for normal program material; 12 to
15dB’s is a more realistic figure.
If operating both channels of the amplifier into a sustained 2 ohm load,
protection circuits within the amplifier could be triggered due to thermal or
over current protection, and the amplifier will shut down. To reset the
amplifier, it must be switched "OFF" then back "ON".
Martin Audio – E1300 Amplifier
E
NGLISH
12
All material © 2007. Martin Audio Ltd. Subject to change without notice.
