Ecler DPA2500T User Manual

Also see for DPA2500T: Service manual

Contents

41. IMPORTANT NOTECongratulations! You are the owner of a carefully designed and manufactured equipment. We thank you fortrusting on us and choosing our amplifier DPA SPM (All purpose) (Switching Power Mosfet).In order to obtain maximum operativity and perfect functioning order, it is most important to carefully read allconsiderations taken into account in this manual before connecting this amplifier.We recommend our authorised Technical Services if any maintenance task should be needed so thatoptimum operation shall be achieved.1.1. PrecautionsThe DPA2500T/4000T consumes a maximum power of 4100VA / 6760VA, we therefore recommend amains wire not inferior to 4mm2 and a (circuit breaker) superior to 25A/230VAC (data for one amplifier).The amplifier should have an earth connection in good conditions (earth resistance, Rg=30Ω or less). Theenvironment must be dry and dustless. Do not expose the unit to rain or water splashes, and do not placeliquid containers or incandescent objects like candles on top of the unit. Do not obstruct the ventilationgrilles with any kind of material.In case there is some type of intervention and/or connection-disconnection of the amplifier, it is mostimportant to previously disconnect the mains power supply.Do not manipulate the output terminals to the loudspeakers when the amplifier is switched on, there arevoltages up to 400Vpp. The output cabling should be connected by a qualified technician. Otherwise only use pre-made flexible cables. There are no user serviceable parts inside the amplifier.2. INTRODUCTIONWith the PAM amplification series, ECLER introduced in early 90's a new concept to the world ofprofessional audio: The use of switching field effect transistors. The integration of these parts for audio applicationsrepresents a firm and spectacular enhancement comparing to conventional amplifiers. These advantages can beoutlined as follows:a) Lower internal resistance than bipolar transistors, which leads to less heating of the amplifier and morepowerful and controlled bass.Conventional Mosfets have a 4 to 7 times higher internal resistance than switching Mosfets.b) The extremely high speed of these devices gives a transparency to the upper frequencies till now onlyachieved by tube amplifiers. This fact also reduces TIM (transitory intermodulation) to very low levels.The SPM-Technology (Switching Power Mosfet) has been developed and patented by ECLER Laboratoriode Electro-Acústica, S.A.The DPA power amplifier line is yet another step forward in the evolution of the SPM technology.DPA amplifiers introduce innovations which probably make them one of the most reliable amplification linesof its class.SOA Contour following protectionThe SOA is the safe operating area of transistors. A good protection system should respect this area and itsshiftings, as the SOA changes as a function of the operating temperature. So, at 80°C it is considerably narrowerthan at 25°C, the start-up temperature. Some manufacturers decide to use protection systems which compromiseon the performance of the components. You get a fair protection, but the performance remains mediocre. Othersprefer to leave "dark" areas between the safe operating area and the activation of protection, which is very riskyindeed.The new SOA contour following protection systems built into the DPA amplifiers guarantees total protectionof the amplifier at any output power, load or operating temperature, as the intelligent electronic circuitry permanentlywatches for changes in the safety area, adapting itself to any situation.The best Damping in an amplifier of its class. In the DPA series, the typical output relays have beensubstituted with an electronic CROW BAR system. This device shunts to ground any signal in case of high voltageswhich could damage the connected speakers. Any kind of relay introduces a mechanical contact in the path of theaudio signal to the loudspeakers. This contact implies a certain degree of wearing and an important reduction of theamplifier's damping factor.