Quick Start

Go to a quiet space, put on a pair of headphones.
Launch What?
Press Space.
Press Right-Arrow if you heard a tone, Left-Arrow if not.
Repeat prior two steps until All done notice appears.
Press Save to copy the audiogram to a file.

Display

Indicator Square Green while a tone is playing
Gain The gain (or amplitude) of the current tone in dB.
Pitch The frequency (or pitch) of the current tone in Hz.
Step Shows the progress through the series test frequencies. The position in the series is not affected by clicking in the graph.

Keyboard

Space / Down-Arrow Play the next tone of the Test Sequence. Repeat the current tone on successive presses until the tone is accepted or rejected.
Up-Arrow Repeat the current tone.
Left-Arrow Reject the current tone. Increase the gain on the next Play, advance to the next frequency when maximum gain reached. Rejected tones are marked with a red dot.
Right-Arrow Accept the current tone. Advance to the next frequency at the lowest gain on the next Play. Accepted tones are marked with a blue dot and are saved for the audiogram.
Backspace Backup through the Test Sequence or tones placed with a click, whichever was the most recent. Removes the marker from the graph.

You can change your mind between accept or reject any time before playing the next tone in the sequence and you can repeat a tone any time before accept or reject. You can change your mind after playing the next tone or tones in the sequence with Backspace. You can also backup through the most recent series of tones placed with a mouse click with Backspace.

Mouse

Click in the graph to Play a tone at the indicated frequency and gain. Accept or reject the tone or continue in the Test Sequence using the keyboard as above. Use this to make adjustments in gains near the threshold of hearing for finer gain resolution than in the default Test Sequence.
Mouse clicks snap (are quantized) to the nearest 2 dB gain and .2 octave intervals, the same as the graph grid. With the default test parameters this is generally not the same as the points in the Test Sequence.

Controls

Name - Include Name in the title and filename of the audiogram.
Binaural, Left, Right - Select the output channel for the test.
Test Tone - Play a brief 1000 Hz tone at 0 dB.
Save - Save the audiogram shown in the graph to an image file.
Reset - Clear the graph and reset the Test Sequence to the beginning.
Exit - Exit What?

Menus

File->Quit Exit What?.

View->Show Waveform A little useless eye-candy.

Parameters->Edit Change the test parameters: start and end frequencies, number of frequency points per octave and number of gain points per 10 dB. The hearing loss range is fixed at 0 to 80 dB. Changes to test parameters are saved between launches.
Parameters->Show Show the test parameters, frequencies, and gains of the Test Sequence.
Parameters->Default Set the test parameters: 125 -> 16,000 Hz, 1 gain point per 10 dB, and 4 frequency points/octave.

Help - Self evident.

Tone Characteristics

Reference level - 0 dB gain is the full-scale digital level, sometimes called dBFS (dB full scale).
Waveform - Sine wave.
Sampling rate - 44,100 samples/second.

The Test Sequence

Tones characteristics (frequency and gain) are determined in two independent ways: 1) from a list of frequencies and gains or 2) as selected by a mouse click in the test graph. The list of frequencies and gains is known as the Test Sequence and can be viewed using Parameters->Show. The frequencies in the Test Sequence are quantized to specific values determined by the number of points per octave parameter. The order of frequencies is randomized at each launch of What? and at each Reset. The gains in the Test Sequence are quantized to specific values determined by the number of points per 10 dB parameter. They are presented in order of increasing gain until accepted.

Tones from the Test Sequence or placed by mouse clicks are combined in the audiogram. They are independent except when backing up with Backspace. What? has separate history lists for the Test Sequence and mouse clicks and backs up through the most recent list, either the Test Sequence list or the mouse-click list but not both.