[JohnM]

Sorry for the late reply on this. The current version of REW only works when using its own measurement sweep signal. The next version (which is coming to the end of its beta testing) includes a Real Time Analyser that allows you to make measurements using random or periodic pink noise test signals played through your system and can also generate periodic pink noise test signals as WAV files to be transferred to CD or other media for replay (periodic pink noise is superior to random pink noise for measurement purposes as it does not require the degree of averaging random pink noise needs to give useable results at low frequencies).