MPA-4250 ORDERCODE D6122
Congratulations! You have bought a great, innovative product from DAP Audio. The DAP Audio MPA- Series bring excitement to any venue. Whether you want simple plug-&-play action or a sophisticated show, this product provides the effect you need. You can rely on DAP Audio, for more excellent audio products. We design and manufacture professional audio equipment for the entertainment industry. New products are being launched regularly. We work hard to keep you, our customer, satisfied.
DAP Audio DAP Audio MPA-4250 Product Guide Warning................................................................................................................................................................ Safety-instructions........................................................................................................................................... Operating Determinations......................................................................................................................
WARNING CAUTION! Keep this system away from rain and moisture! FOR YOUR OWN SAFETY, PLEASE READ THIS USER MANUAL CAREFULLY BEFORE YOUR INITIAL START-UP! SAFETY INSTRUCTIONS Every person involved with the installation, operation and maintenance of this system have to: be qualified follow the instructions of this manual CAUTION! Be careful with your operations.
Make sure that the amplifier is turned down, before turning the power on or off. So you can avoid supersonic frequencies, which could damage your speakers. Don't put your equipment next to TV, radio, etc., because of interference or distortion. If you connect other parts of the system, be careful of ground loops. The best way to avoid ground loops is connecting the electrical system ground to one central point ("star" system). In this case the mixer can act as a central point.
Description of the device Features The MPA-4250 is a professional high power Public Adress Amplifier: • 4 independent channels • 4 sets of bas treble and volume controls • 4 LED level meters with protection indicator • 4 balanced inputs for Mic/ line and input sensitivity control • Telephone paging function, Phoenix type terminal block input type • Low impedance 4Ω, 8Ω and high impedance 25V/ 70V/ 100V output • Output power: 250W(RMS) x 4 • Selectable input types: COMBO (TRS & XLR) and terminal type • Switc
9. Aux 1. Use to adjust the aux 1 input level. 10. Power LED. Indicates that the amplifier is turned on. 11. AC Power Switch. This is the main Power switch. Press to turn the amplifier on. 12. Chime button. Activates the Chime circuit. If pressed in, the chime can be started by using the priority contact at the backside (31). At the same time all inputs except input 1 will be muted. 13. Siren button. Pressing this button will start the siren. 14. Input. Use to adjust the input volume level for input 1-4.
26. 25V terminal. Connect this terminal to the + terminal of your 25V speaker(s). In case of using several speakers make sure all speakers are wired in parallel. The total power rating of the 25V-speakers for each channel should never exceed 250W. 27. 8 Ω terminal. Connect this terminal to the + terminal of your 8 Ω speaker(s). In case of using several speakers make sure that the total speaker load is 8 Ω. The total power rating for each channel of the low impedance speakers should be at least 250W. 28.
Operation Installation Remove all packing materials from the MPA-4250. Check that all foam and plastic padding is removed. Secure the equipment into a 19" rack. Connect all cables. Connecting Power / Circuit Size Requirements. The actual current draw, the amplifier demands from the AC mains, depends on many factors (its load, output level or the crest factor of its program material).
Example 2: using the 4Ω output with four 4Ω speakers Fig. 4 Example 3: using the 8Ω output with two 4Ω speakers. Fig. 5 In a low impedance system, the total speakerload should always match the amplifier impedance This to avoid overloading the amplifier. The total speaker power should be at least the power of the amplifier to avoid damage to the speakers. High impedance outputs If using either the 25V, the 70V outputs or the 100V outputs, note that all speakers should be wired in parallel.
Connection Cables Take care of the connector cables, always holding them by the connectors and avoiding knots and twists when coiling them: This gives the advantage of increasing their life and reliability, which is always to your advantage. Periodically check that your cables are in good condition, that they are correctly wired and that all their contacts are in good condition: a great number of problems (faulty contacts, ground hum, discharges, etc.
Fig. 8 Maintenance The DAP Audio MPA-series requires almost no maintenance. However, you should keep the unit clean. Disconnect the mains power supply, and then wipe the cover with a damp cloth. Do not immerse in liquid. Do not use alcohol or solvents. Keep connections clean. Disconnect electric power, and then wipe the audio connections with a damp cloth. Make sure connections are thoroughly dry before linking equipment or supplying electric power.
Product Specifications Model: Power supply: Fuse: Inputs 1 – 4: Frequency response: Tone control: Total harmonic distortion: Signal / noise ratio: Priority for MIC 1: Outputs for speakers: Outputs for speakers: Output power: Input impedance: Indicator: Dimensions : Weight : DAP Audio MPA-4250 230 VAC 230V: 8AT 115V: 15AT Sensitivity: Mic: -55dB balanced Line: -16dB balanced High filter: 150Hz (-3dB) Phantom: 48V Telephone paging function sensitivity: 120mV Mic: 60Hz – 12kHz (-3dB) Line: 30Hz – 18kHz (-3dB
Appendix 1: Block diagram MPA-4250 Fig.
2008 Dap Audio.
