Test signals can be used to measure your system for room correction, and also for general audio test purposes.
Warning: test signals are loud and might damage your equipment if played at high volume. Be sure that volume is low before selecting a test signal.
Apart from the “(With EQ)” versions, all these test signals bypass the rest of the DSP signal processing chain. So EQ, balance, width and other settings are ignored while the test signals are playing.
The test signals are:
- Off. When the test signal is set to “Off”, music is played normally. When a test signal is selected, the currently playing music is replaced with a generated signal.
- Left/Right channel identification signal.
- In the left channel: an ascending sweep, with Morse code “Left”.
- In the right channel: a descending sweep, with Morse code “Right”.
- Sweep. A logarithmic swept sine wave from 10Hz to Nyquist (22.05kHz, for a 44.1kHz sampling rate) over 45 seconds, at -12dBfs. Useful for room measurement.
- Sweep (short). A logarithmic swept sine wave from 10Hz to Nyquist over 20 seconds. Useful for room measurement when you don’t want to annoy everyone too much.
- Sweep (With EQ). The sweep, but with the EQ processing chain enabled. Can be used to verify that a correction filter is working properly.
- Pink noise. A filtered random noise with equal energy per octave. Based on a white noise at -12dBfs, but will occasionally peak higher. This is “mono”, i.e. the same signal in each channel.
- Pink noise (With EQ). Mono pink noise, but with the EQ processing chain enabled. Useful for adjusting left/right balance (you should hear a waterfall-like column of sound in the centre of th soundstage).
- Pink noise (stereo). Pink noise independently generated for each channel.
- Pink noise (stereo, with EQ). Pink noise (stereo), but with the EQ processing chain enabled.
- White noise peaking at -12dBfs. Random noise with flat frequency spectrum.
- Sine. A pure sine wave at -12dBfs.
- Quadrature. Left and right channels 90 degrees out of phase, pure sine wave at -12dBfs.
- Square. A bandlimited square wave at -12dBfs.
- Triangle. A bandlimited triangular wave at -12dBfs.
- Sawtooth. A bandlimited rising sawtooth at -12dBfs.
- Intermodulation test. A pair of sine tones, at 19kHz and 20kHz, combined to -12dBfs.
Test signals use the dither selected in the configuration file. Apart from quadrature, all signals are dual mono, with identical values in each channel (apart from any dither).
