FOG INFORMATION 1. IMPORTANT NOTICE: DG NOY MODIFY THIS UNIT This product, wham installed as indicated in the instructions contained in this manual, meets FCC requirements. Modifications not expressly approved by Yamaha may void your authority, granted by the FCC, to use the product, 2. IMPORTANT: When connecting this product to accessories and for another product use only high quality shielded cables, Cables supplied with this product MUST be used. Follow all installation instructions.
Thank you for purchasing the Yamaha P4050 Power Amplifier. The P4050 is a fine example of the experience and skill Yamaha has developed for the production of superior audio and PA equipment. It is not only highly reliable and stable, but also very compact and light. The amplifier offers three output modes — 2-channel, 3-channel and 4-channel amplification — which are selected by simple switch operation.
PRECAUTIONS Avoid Excessive Heat, Humidity, Dust and Vibration Keep the unit away from locations where it is likely 1o be exposed to high temperatures or humidity — such as near radiators, stoves, etc. Also avoid locations which are subject to excessive deist accumulation or vibration which could cause mechanical damage. Amplifier Ventilation The power amplifier is equipped with cooling fans. It is important 1o ensure that proper air flow can be maintained.
OPERATION M FRONT PANEL Handle @ POWER Switch & Indicator Pressing this switch turns the power ON, and pressing again turns the power OFF. The indicator lights when the power is ON, THERMAL Indicator ‘When the heat sink temperature exceeds 80 deg C, the cooling fan will operate at high speed and the thermal indicator will light, If the indicator remains lit for a long time, check for cooling problems such as blocked air vents. For proper ventilation details, refer to the “Installation Details” on page 8.
@ INPUT Terminals (screw type) These screw terminals can be used for balanced and unbalanced input signal connection. t—_ A/D G I@@@ Ho! Cold {3 Ground ® INPUT Connectors (TRS Phone type) These balanced TRS connectors accept balanced and unbalanced input signals. Tip=hot, Ring=cold, Sleeve=ground.
CONNECTIONS Combining the INPUT MODE and OUTPUT MODE switch settings, the amplifier offers the following six application setups, + 4 inputs/4 outputs « I input/4 outputs * 3 inputs/3 outputs 1 input/3 cutouts » 2 inputs/ 2 outputs » 1 input/2 outputs Amplifier with 4 inputs and 4 cutouts Amplifier with 1 input and 4 outputs INPUT ATT. AMP. CUTOUT INPUT ATT. AMP.
Amplifier with 3 inputs and 3 outputs Amplifier with 1 input and 3 outputs INPUT ATT. AMP, OUTPUT !NUT ATT. AMP, OUTPUT adl AL To INPUT terminals To INPUT terminals Mixer or per-amp output [ e [ Mixer or pregame outputted answered e [— Speaker Speaker Speaker o R AsL 50w 0w 140w Amplifier with 2 inputs and 2 outputs Amplifier with 1 input and 2 outputs INPUT ATT, AMP, OUTPUT INPUT ATT.
INSTALLATION DETAILS Make sure that the amplifier has adequate ventilation. The unit is equipped with a twin fan cooling system. For this reason the airflow 1o the front and side panels should not be blocked. B Permanent Rack Mounting ‘When high-powered amplifiers are rack mounted, the heat generated from each amplifier can build up inside the rack causing excessive temperatures. This is especially true if there is no rear opening in the rack mount enclosure.
CAUTION FOR SPEAKER CONNECTION 1. Turn off the POWER switch. 2. Remove the cover attachment screws and remove the protective cover from the speaker terminals, * The protective cover is equipped with British model and general model. Coyer attachment scows Protective cover 3. After removing approx.
CLEANING THE FILTER ELEMENTS To ensure adequate cooling air intake, the filter element must be cleaned when it has become clogged. The following points describe the cleaning procedure: 1. Make sure the power to the amplifier is OFF. 2. Remove the power plug from the AC mains socket. 3. Remove the filter elements, and wash in plain water, If the filter elements are exceptionally dirty, detergent (washing-up liquid) may be used. 4. Dry the filter elements thoroughly.
SPECIFICATIONS POWER OUTPUT LEVEL 4 CHy . 5OW + S0W 4 50W + S0W; RL = 8 ohms, kM2, THD = 0.1 % TOW £ 70W + 70W + 70W; RL = 4 ohms, kH2, THD = 0.1 % 2CH: 140W + 140W; Rl = 8 ohms, kHz, THD = 0.
