Wiring
Connect an ASIO audio card to the PC where the FIR wizard is running, with its proper connection
(USB, Firewire, etc.). Connect the (normally balanced) ASIO card output (XLR or TRS) to the balanced
input (XLR) of the DSP device (e.g the LPP Controller).
Connect the microphone output to the mic input (normally XLR) of the audio card and turn the
phantom power (if needed). If the mic has its own preamplifier, connect it to a line input of the audio
card. Finally, connect the DSP device to the loudspeaker system.
Therefore, in the FIR Wizard “Wiring and levels” page, select the ASIO audio card and the right
input/output channels. using the list box at the top of the screen,
Now, click the “Test” button to start the microphone test, making sure the loudspeaker amplifier
volume is low. Then, start rising the amplifier volume untill a strong but not annoying “sine sweep” is
heard. Click “Test” button again and adjust the microphone preamp gain until the measured signal
peak reach roughly the -6 dBFS value.
If during the microphone test some glitches occur, it is probably due to a latency issue of the sound
card. To solve the problem, open the sound card control panel clicking the “ASIO Control Panel”
button and try to choose an higher latency value (or, equivalently, a large buffering).
Click “Next” button and you are ready to measure the IR of the loudspeaker.
