All of the test tones I've used generate pretty loud "white noise" when played individually, but I don't see any reason that they have to be directly reproducing "reference level" playback for a proper calibration process. Any test tone should include some instructions in recommended use - I have seen folks post that at least one calibration disc (possibly AVIA?) recommends calibrating to 85dB with their test tones, whereas the internal test tones in many receivers and processors (including the Outlaw gear I've used) are intended for use calibrating to 75dB. That way the designer can establish a tone that is "x" dB lower than reference level. It would certainly be much easier on the ears for the lengthy sustained full-spectrum tones to be scaled back from reference level (can you imagine trying to think coherently while listening to a 105dB test tone for the eight or more times required to work all the way through a 7.1 surround setup?), whereas DVD's or other source material tend to have shorter-duration moments that spike to reference level over a limited frequency range.