How to measure loudspeaker frequency response uncalibrated?

To measure the frequency response of a loudspeaker, no level calibration has to be performed. Load the setup named LoudspeakerMeas from the Setups Toolbar (usually situated at the lower right corner, can be found from View->Setups Toolbar). Perform a measurement (Measurement->Start Measurement) with a microphone connected to the input (left channel) and the loudspeaker connected to the output (left channel).