Yamaha XM4220 Stereo System User Manual


 
4
Controls and Functions
Front Panel
1 POWER switch and indicator
This is the main POWER switch. Press to turn on the
amplifier. Press it again to turn off. The POWER
indicator lights up when the amplifier it turned on.
2 PROTECTION indicator
When the protection system is active, the PROTEC-
TION indicator lights up and the speakers are auto-
matically disconnected from the amplifier’s outputs.
The protection system activates in the following
situations:
When the amplifier is turned on
The protection system activates for approximately
three seconds when the amplifier is turned on. After
three seconds, the protection system deactivates
automatically and the amplifier is ready for normal
operation.
If a DC voltage is detected at the amplifier’s
outputs
The protection system activates if a DC voltage is
detected at the amplifier’s outputs. Once the DC
voltage problem is corrected, the protection system
deactivates automatically and the amplifier is ready
for normal operation.
If the amplifier overheats
If the amplifier overheats, the protection system
activates. In this case, you should turn off the ampli-
fier and allow it time to cool down. When it has
cooled down, the protection system deactivates
automatically and the amplifier can be turned on again
ready for normal operation. See the Precautions
section of this Owner’s Manual for ways to prevent
the amplifier overheating.
3 CLIP indicator
A channel’s CLIP indicator lights up when its output
distortion exceeds 1% (i.e., clipping). Output signal
clipping is typically caused by excessive input signal
levels.
4 SIGNAL indicator
A channel’s SIGNAL indicator lights up when its
output exceeds 2 V rms, which is equivalent to 1/2
watt into 8 ohms, or 1 watt into 4 ohms.
1
2
3
4
* The illustration shows model XM6150.