Input B Input AIn C In A 32 32 32 32In BIn DInput CInput D+ - + - + - + -Input B Input AIn C In A2323 2323In BIn DInput CInput D+-+-+-+-3 INSTALLATIONUSER MANUALQ - P O W E R S E R I E SP. 3Q - P O W E RS E R I E S3.4 CoolingUnder normal operation of the power amp, overheating should never be aproblem. The air is taken in from the front and out through the back. It is ofcourse essential that while the power amp is running air is able to circulatearound it freely.The efficiency of the cooling will depend on the immediate environment (e. g.an enclosed rack, direct sunlight) and on whether the front filter is clogged. Ifthe amp is installed in a case the open area at the back of the case must be atleast 40 cm². This area should be in line with the amp.If this can not be achived a forced ventilation system has to be used.3.5 Wiring3.5. Input ConnectorsXLR: Pin = GroundPin 2 = Hot (inphase, +)Pin 3 = Cold (out of phase, -)Euroblock connector: Pin = Hot (inphase, +)Pin 2 = GroundPin 3 = Cold (out of phase, -)Make sure to always use high-quality symmetrical (balanced) shielded cable toensure maximum audio quality.Please do not simultaneously attach two independent signal sources to the XLRand Euroblock input connectors of the same channel. This could lead to volumeand audio quality loss and could damage the connected signal sources.3.5.2 Output ConnectorsThe two SPEAKON connectors are connected to the channel A to D power ampli-fier outputs. The pin configuration of the SPEAKON-connectors is as follows:Top Right: Pin + Channel A signal +Pin - Channel A signal -Pin 2+ Channel B signal +Pin 2- Channel B signal -Top Left: Pin + Channel C signal +Pin - Channel C signal -Pin 2+ Channel D signal +Pin 2- Channel D signal -