10711 PREPARING FOR CALIBRATIONThis chapter explains very important tips to ensure a smooth and safe calibration process, as well asimportant recommendations for microphone placement in order to perform high qualitymeasurements.11.1 VERY IMPORTANT TIPSImportant Notes:• Active Crossovers need to be calibrated prior to Optimizer, Level, or Delay Adjustments.• Master 48 kHz clock modes should be used for measurement. (Factory default for themicrophone input.)Avoiding feedback loops:• Always MUTE the processor as the first step of the calibration procedure. Muting the outputs does not affect thecalibration signal.• Be careful with feedback issues when you change the routing you could make dangerous feedback loops betweenthe microphone and the loudspeakers.Avoiding warning messages during calibration:• Disable the subwoofer’s built-in filters: a narrow bandwidth can disturb the measurement.• Adjust levels between amplifier/active speakers before calibration to avoid dangerous level jumps.11.2 CHECKLIST BEFORE YOU STARTPlease go through the following checklist to make sure you are ready to start the calibration process:• You’ve read carefully the whole chapter about the SDP-75’s Essential Tools and Settings that you’ll be usingthroughout the calibration process.• The speaker layout (including multi-amplified speakers) has been specified in the SDP-75 Speaker/RoomSetup Tool.• The routing of the speakers/drivers has been verified by playing pink noise with the SDP-75 Speaker/RoomSetup Tool.• All the speakers (including the subwoofers) are installed in their final positions and orientations, and connectedto their amplifiers in the proper polarity.• The measurement microphone is switched OFF, placed securely on a mic stand or camera tripod, andconnected to the SDP-75 MIC input.• The MIC input is selected as a source for a 5 pin XLR microphone, or ANALOG BAL IN 1+2 (MIC 4 XLR) for a 4XLR microphone• You have access to the Advanced Settings user interface via a screen directly connected to the SDP-75, orthrough a VNC client.
