TOA Electronics TA 1400 - Manual (Page 11)

clip and is therefore the highest power level one can obtain without completely obliterating the
program.
Last, the "normal operating power", as defined by the safety standard IEC 65/ANSI/UL 6500 and
used by a majority of safety agencies. The normal operating power is measured using pink noise,
with an average output power equal to 1/8 of full power. The one eighth of the total power is as
loud as you can play music while making some attempt to avoid obvious clipping. It also
corresponds to headroom of 9dB, which is very low for normal audio program.
MAX OUTPUT POWER MAINS INPUT POWER
Power 1/3 Power 1/8 Power Idle
[W] note 1 note 2
TA 1400 8 ohms 2x 425 690 430 90
4 ohms 2x 700 1150 760 90
2 ohms 2x 1050 1925 1225 90
note 1 Average power with music as program source. The amplifier driven to clip level.
note 2 Normal music power with 9dB headroom, IEC standard power rating.
Table 1.
6.7.1 Calculation
The current draw can be calculated by dividing the mains input power by the mains voltage.
We recommend you to design the power distribution for at least the current at 1/8 power, and 1/3
power for heavy-duty demands like discos etc.
The heat power can be calculated as in the following example:
We consider headroom of at least 9dB and a 4 ohms load on an amplifier producing 700 watts per
channel. The 1/8 power per channel is accordingly; 700 / 8 = 87 watts, and total output; 2 x 87 =
175 watts.
The power consumption according to the chart above is then 1200 watts.
The heat power produced is the difference between the power consumption and output power;
1200 - 175 = 1025 watts per amplifier
.
7 CONNECTIONS
7.1 Input connections
7.1.1 Balanced inputs
XLR Input connectors are active balanced and wired according to the IEC 268, that is pin 2 hot, and
wired in the following way:
PIN 1
GROUND/SHIELD
PIN 2 HOT (+)
PIN 3 COLD (-)
Figure 4. XLR input connector
Figure 5. XLR balanced
Tannoy Limited
TA 1400 User Manual 11-06-02
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