Questions-answers regarding the use of the ODEON measuring system.

A: The ODEON measuring system is very flexible. Only elementary equipment is needed for an initial measurement: A microphone and a loudspeaker, connected to the built-in sound card of a portable PC. However, the better is the quality of the measuring equipment the highest is the accuracy of the results. Built-in sound cards often use low-quality filters which introduce distortion and additional background level in the recorded response. USB audio interfaces of moderate prices, indented for gaming or music recordings, can work pretty well. Power supply directly from the USB port is preferable, for increased portability. A flat frequency response microphone and loudspeaker can help to obtain enough signal to noise ratio for as many as possible octave bands. If someone wishes to experiment with some other stimuli than the sweep signals used by ODEON -gunshots, balloon/paper bag popping- only a mobile recorder is necessary. The impulse response can be recorded as a .wav file and be post-processed afterwards in ODEON.

Q: When I try to lunch the measure impulse response tool an error message appears: "In Prepare error - closing convolver!".

A: The measuring system in ODEON requires that both an input and output audio device are available. Some sound cards make their devices unavailable to Windows (Vista, 7, 8) if no cable is connected. Connecting the microphone to the microphone input on the sound card (or any 3.5 millimeter jack) solves the problem. You can then go into the Measurement setup (Options>Program Setup>Measurement Setup) and choose the correct microphone (and playback device too) from the audio devices tab.