Owner’s Manual M120
WARNING TO PREVENT THE RISK OF SHOCK OR FIRE. DO NOT USE THIS CORD WITH AN EXTENSION, RECEPTACLE OR ANY OTHER OUTLET UNLESS THE BLADES CAN BE FULLY CUT. PLEASE MATCH THE WIDE BLADE WITH THE WIDE SOCKET OPENING. TO PREVENT THE RISK OF SHOCK OR FIRE. DO NOT EXPOSE THIS APPLIANCE TO RAIN OR MOISTURE.
M120 Table of Contents Introduction ............................................................................................................................................................................ 2 Features .................................................................................................................................................................................. 3 Controls.....................................................................................................
M120 Introduction M120 Welcome! Thank you for choosing this Quest Commercial M-Series Mixer Amplifier! Quest Commercial Mixing Amplifiers are the ultimate solution for sound distribution systems in small to medium sized commercial premises, delivering the best and highest quality audio at an affordable price. These models have a constant voltage power amplifier allowing use at 25/70V or at low impedance of 4 or 8 Ohms. The M120 can deliver a power of 120 Watts.
M120 Features The M120 mixer amplifiers are complete all-in-one mixer amplifier solutions for commercial and industrial applications. These low-cost units offer all the necessary features in a simple format. • Three (3) microphone inputs and two (2) line inputs (terminal block, RCA and 3.5mm on the front panel). • Rated power output: 120 Watts. • A 2-band tone control helps correct the overall sonic response of the PA system.
M120 M-Series – Front Panel Presentation [Figure 1.1 Front panel diagram] 1. Input Channel Volume – These three knobs determine the level of the sound sources connected to the inputs. 2. Tone Control – These two knobs adjust the overall frequency response of the system. They allow up to 10dB of cut/boost on the 100Hz and 10kHz bands. 3. Master Volume Control – This knob determines the overall volume of the system. 4.
M120 M-Series – Back Panel Presentation [Figure 1.2 Rear panel diagram] 1. Power Cable. 2. Speaker output connector – This 5-contact terminal block connector allows the use of 25V or 70V constant voltage loudspeakers, as well as low impedance loudspeakers of 4 or 8 ohms. 3. MoH (Music on Hold) terminal - This 3-contact terminal block connector allows the mixer to be linked to a commercial telephone system to provide a music source when a call is put on hold.
M120 Installation CAUTION: Before you begin, make sure your mixer amplifier is unplugged from the power source, the power switch is in the "OFF" position, and all volume controls are set to minimum level (turned counterclockwise). Location: Take the unit out of its packaging (keep it for any return to the workshop). The M120 mixing amplifier can be installed in a standard 19” equipment rack or on a shelf.
M120 Installation Using a constant voltage system – continued The same principle applies to constant voltage audio systems. A transformer connected to the output of the amplifier increases the voltage and reduces the output current, allowing the use of long, smaller-diameter cables to link multiple speakers with step-down transformers. For economy, the 70V standard was adopted in the United States because electrical conduit is required on lines with voltages greater than 100V peak-to-peak.
M120 Installation Connecting sound sources Then connect the sound source to the terminal block input connectors on the back. If your console has balanced outputs, use balanced three-conductor connections and connectors (you can use unbalanced connections, but you'll get better sound quality and less noise if you use balanced connections). Set all input level controls (on the front) to minimum (“-MIN“). Then connect the mains lead to an earthed mains socket.
M120 Wiring Guide Wiring plans Choose the input connector and the appropriate cable for each source. We recommend the use of pre-assembled or professionally assembled 22-to-24-gauge balanced cables. Figure 2.1 shows the connection diagrams for the different connectors. RCA input connectors can also be used as unbalanced inputs.
M120 Wiring Guide Wiring plans – Continued Choose the output connector and the appropriate cable for each source. For the amplifier output connectors, we recommend the use of pre-assembled or professionally assembled speaker cables of high quality and of sufficient gauge. You can use pluggable terminal blocks for your output connectors. To prevent the possibility of shorting, wrap or insulate exposed speaker connectors.
M120 Wiring Guide Speaker connections are shown in Figure 2.2 [Figure 2.2 How to connect speakers] WARNING: Never use the low impedance (4Ω / 8Ω) and high impedance (25V, 70V) outputs simultaneously. [Figure 2.
M120 Operations Power On Press the power switch on the front to turn on the device. The Power indicator lights up, as well as the Protection indicator. The Protection indicator turns off after approximately five seconds (a click is then heard). Apply an input signal of approximately +4 dBu. Then set the input level control to the center position While the signal is audible, gradually increase the master level control (Master Volume) to on the desired sound level.
Operations Input Signals Gain Control. The Quest Commercial Mixer Amplifier can accept wide range and variable input signals thanks to the gain adjustment potentiometers. Adjust the gain potentiometer within a range of 44dB to accommodate different external equipment. Figure 3.2 shows the detail of input sensitivity. [Figure 3.2 Acceptable input sensitivity per channel] Priority Control The Quest Commercial Mixer Amplifier has a two-level priority mute function.
M120 Operations Using the Music on Hold (MoH) output to power a 2nd zone For use for 2 or more zones, the example below illustrates the installation that can be done when the unit is used in conjunction with a 2nd unit. The MOH connector of the first is used to power the second and so on.
Block Diagram 15 M120
Specifications Performance M120 Input Sensitivity for full output at maximum gain Balanced Microphone inputs -50dB ± 3dB Unbalanced & AUX inputs -30dB ± 3dB Telephone Paging -21dB ± 3dB Frequency Response at 1watt from speaker out tap, 80Hz ~18kHz +1.5/-3dB Tone Controls 100Hz,10kHz ±12dB ±3dB Signal to Noise Ratio at rated power output Less than 90dB Crosstalk at all control maximum -70dB at 1kHz Rated Output Power at THD 0.
