In article ,
Serge Auckland wrote:
As an aside, in radio, digital metering is still done on conventional
BBC style PPMs, which under-read by anything between 1-4dB depending on
the programme content.(some will say even up to 7dB) I and others have
tried persuading radio stations to use a true-peak meter, even if it is
calibrated with the familiar BBC 1-7 scale. The universal reaction was
that the signal was too quiet, and everyone prefered to go back to a
meter they were familiar with, even if it didn't tell the truth, and
rely on the 10dB headroom between the +8dBu UK peak operating level and
the +18dBu maximum to accomodate any unseen peaks. US practice is even
less precise as they still use VU meters and rely on the 20dB headroom
between 0VU (+4dBu) and their +24dBu=0dBFS.

The great beauty of the analogue PPM is that it gives a good indication of
perceived loudness as well as the electrical value. It's the Holy Grail to
find something which does this better - but it hasn't happened yet.

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Dave Plowman London SW
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