Basic instructions on using the applications
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The metering applications that use PortAudio (paqt_meter,
paqt_bendy_meter, pa_logger )  might require you to adjust the gain
carefully on the audio input to your computer.  It is likely, especially
if you are using an analogue audio input, that there are one or more
gain controls that will affect the level of the signal that is received
by the application.  If the gains controls are set incorrectly then the
meter readings will be incorrect.

A simple way to check the input level alignment is to use paqt_meter
in its PPM mode.  paqt_meter uses the ITU-R BS.1770 subjective loudness
algorithm by default, but, if you click your mouse in the window and then
press the "p" key on your keyboard, it will become a PPM.  

Note that the PPM has 4 different modes of operation: Mono, "AB" (stereo),
"M6", and "M3".  To select these modes you press the "m", "a", "6", or
"3" key respectively.  For alignment purposes you should use mono or AB.
Do NOT press "s" to get stereo - "s" is for "slow", not for "stereo".
A summary of the keyboard controls can be seen if you hover the mouse
in the meter window for a couple of seconds.

If you use a stereo 1kHz sine wave at 0dBu ( 0.775V RMS ) then you should adjust
the gain controls on your mixer device so that the meter reads PPM 4 on both
channels.

To change paqt_meter back to BS.1770 loudness, press the "l" key.
The meter should now read -18 LKFS.  If you used a mono 1Hz sine wave,
instead of stereo, the meter should now read -21 LKFS.

Paqt_aoc is largely signal level independent.  However, using paqt_meter,
or any other meter, to ensure that your signal is comfortably between
the noise floor and clipping is recommended.  


F_meter, since it reads from files, is not affected by these controls.