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Introduction
Thank you for purchasing a Yamaha 6150, or 4220 XM Series Power Amplifier.
The XM Series of power amplifiers was developed from Yamaha’s wealth of experience in
building PA equipment and its tradition of careful attention to every detail of circuit design. These
power amplifiers feature high power and superb quality together with superior reliability and
stability, guaranteeing the highest possible audio performance.
Main features include
• Six amplifiers (four on the 4220) that can be used independently or in stereo pairs. Channel
pairs can also be bridged.
• Balanced XLR and Euroblock connector inputs, 5-way binding post outputs.
• Each channel features a switchable HPF, which filters frequencies below 80 Hz, a detented
attenuator, and SIGNAL and CLIP indicators.
• The input signal connected to channel A can easily be fed to the other channels using the
CH A TO ALL CH switch.
• Protection includes power on/off muting, DC detection, temperature, and protection
indicator.
• Variable-speed, low-noise cooling fan system ensures high reliability even under the most
demanding conditions.
This Owner’s Manual applies to the XM6150 6CH and XM4220 4CH power amplifier. In order
to take full advantage of your power amplifier and enjoy long and trouble-free operation, please
read this Owner’s Manual carefully before using your XM Series Power Amplifier.
WARNING: THIS APPARATUS MUST BE EARTHED

IMPORTANT

THE WIRES IN THIS MAINS LEAD ARE COLOURED IN
ACCORDANCE WITH THE FOLLOWING CODE:
GREEN-AND-YELLOW : EARTH
BLUE : NEUTRAL
BROWN : LIVE
As the colours of the wires in the mains lead of this apparatus may
not correspond with the coloured markings identifying the terminals in
your plug, proceed as follows:
The wire which is coloured GREEN and YELLOW must be
connected to the terminal in the plug which is marked by the letter E
or by the safety earth symbol or coloured GREEN and YELLOW.
The wire which is coloured BLUE must be connected to the terminal
which is marked with the letter N or coloured BLACK.
The wire which is coloured BROWN must be connected to the
terminal which is marked with the letter L or coloured RED.
* This applies only to products distributed by YAMAHA KEMBLE
MUSIC (U.K.) LTD.