The Speaker Equalization calibration sequence in SoundCheck includes limit steps as a fail safe to prevent damage to the speaker during the calibration process. If one of these limits fails, an error message is generated. Let’s take a look at the most common message and how to work around it.
What does the “NO SIGNAL DETECTED” warning mean?
This error message is a little misleading because before you saw it displayed on your screen, you probably heard a brief 1 kHz signal playing out of your source speaker. The 1 kHz signal is used to calculate the gain of the output signal path (combined gain of the audio interface, audio power amplifier and source speaker). The error is generated when the gain value is below 10 dB. In most cases, this value will be exceeded and the error will not be encountered but if you do encounter the error, the calibration sequence can be modified.
Warning: Calibration sequences by default have "Read Only" properties. Default calibration sequences should never be overwritten! When modifying a calibration sequence, always create a new instance by using File > Save As, so the default sequence remains intact.
To modify the sequence, open the Speaker Equalization sequence through File > Open > Sequences > Calibration > Calibration - Output > Speaker Equalization.sqc
Create a new copy of the sequence through File > Save As, and give a unique name to this sequence copy. “Speaker Equalization 5db Sensitivity”, for example and save it to the same location as the original sequence.
Next, open Step 7, Lim - Test for Signal. By default, this step applies a 10dB lower limit at 1kHz. Adjust this level until the speaker’s output is above the limit level, while also keeping the limit level high enough for SoundCheck to distinguish between the test signal and background noise. For example, this limit could be changed to 5dB at 1kHz.
Once you edit and save the sequence, run it from the Calibration editor as you would with any other Calibration sequence. The modified sequence will appear and can be selected in the Calibration Sequence dropdown list along with the other default sequences.
Note: If you would like to determine the actual gain of your output signal path, you can run the attached (link below) sequence. The sequence is compatible with all versions of SoundCheck going back to SoundCheck 17.
Download the sequence to your local machine and use the File > Open function to load it (it is not designed to be run from the calibration editor). After the sequence is run, the value "Level Check Average" shown on the final display is the gain of the signal path.
The sequence uses the Reference Mic input signal path and the Direct Out 1 output signal path. In Calibration, Direct Out1 should be assigned to whatever Hardware Output Channel is connected to your amplifier and source speaker (or powered speaker).