[LAD] audio meters nostalgia

Fons Adriaensen fons at kokkinizita.net
Sun Apr 13 20:24:29 UTC 2008

On Sun, Apr 13, 2008 at 10:04:51PM +0200, Florian Schmidt wrote:

> On Saturday 12 April 2008, Fons Adriaensen wrote:
> > The PPM is a pseudo-peak meter. It will indicate 80% of
> > the steady-state value for a 10ms burst, and fall by 24db
> > in 2.8s. Each scale division (1..7) represents 4dB. It is
> > calibrated to indicate '7' (+12 dB on the EBU scale) for
> > 0dB FS.
> Excuse my ignorance, but what's a steady-state value?

The value it would show for a continuous signal of constant
amplitude. So for a 10 millisecs burst the meter will 
indicate 2 dB below the true amplitude. This defines the
rise time.


Laboratorio di Acustica ed Elettroacustica
Parma, Italia

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