6
6. NOMENCLATURE AND FUNCTIONS
[Front]
1. Power switch [ON/OFF]
Power is switched on and off with each depression
of this switch.
2. Power indicator [POWER]
Lights blue when the power is switched on.
3. Input level controls
[CH 1 (BRIDGE 1), CH 2, CH 3 (BRIDGE 2), CH 4]
Adjust the input level of each channel.
4. Ventilation panel (Air Vent)
A filter is located inside the ventilation panel.
To clean the filter, remove the ventilation panel.
(See p. 13; Cleaning the Filter.)
5. Indicators [INPUT, OUTPUT, PEAK, PROTECT]
The indicators are as follows from left to right:
• Input indicator [INPUT]
Lights green regardless of the input level control
setting when an input signal level exceeds about
–20 dB.
• Output indicator [OUTPUT]
Lights yellow when an output level exceeds
about 1 W at an 8
Ω
load (DA-550F) or 20
Ω
load (DA-500FH).
• Peak indicator [PEAK]
Lights red when an output signal clips (distortion
occurs).
• Protection indicator [PROTECT]
Lights red when the protection circuitry is
activated. (See p. 12; Protection Operation List.)
When the power is switched on, this indicator
lights for about 2 seconds and then extinguishes.
When a bridge connection is made
(DA-550F only)
• When Channels 1 and 2 are bridge-
connected (BRIDGE 1 ON/OFF switch (10)
is set to ON), the CH 1/BRIDGE 1 level
control adjusts the input levels of Channels 1
and 2. In this event, the CH 2 level control
cannot be used.
• When Channels 3 and 4 are bridge-
connected (BRIDGE 2 ON/OFF switch (10)
is set to ON), the CH 3/BRIDGE 2 level
control adjusts the input levels of Channels 3
and 4. In this event, the CH 4 level control
cannot be used.
1
2
3
4
5
DA-550F
1
2
3
4
5
DA-500FH
