The Loudness filter can make the sound up to 5.5 dB louder, without causing higher peaks
(hence clipping) in the output. This filter is especially useful for FM, AM or internet
radio stations that want to sound loud - or actually: louder than their competitors.
Note that for certain types of sound, that are already very loud, this filter may slightly
degrade the sound quality. Therefore it should not be turned on for normal music listening.
But even at the highest setting, the amount of degradation is still clearly less than that
of many commercial FM stations, which use a similar filter, and the Loudness filter detects
most of these sounds and turns itself down a bit to reduce most ill effects.
The Loudness filter uses a relatively large amount of processing power. For values above
1.25 the processing power is larger than for values up to 1.25. A setting of 1 means that
the filter is turned off.
If CPU usage is set to High quality, an extra
filtering step is added to reduce the quality loss that this filter causes. This requires
a lot of extra processing power, and may not even run on slower Pentium 4 PCs. If the
input has a very high samplerate (above 60 kHz), this is also the case when
CPU usage is set to Normal quality.
Important: If you use the Loudness filter, and the Post Amp slider
is set at (or just below) 1, make sure that HARD LIMIT is
enabled to avoid distortion caused by clipping. If you use Stereo Tool to prepare an FM
signal, always turn HARD LIMIT on when using the
Loudness filter, regardless of the Post Amp slider
setting.
This option requires registration.
In the unregistered version of Stereo Tool, a short message "This sound is processed by Stereo Tool. Go to stereotool.com for more information"
will be played once every 24 hours.
The first time it is played is 24 hours after Stereo Tool is started,
so this should not interfere if you run Stereo Tool for less than 24 hours at a time.
