Re: Question on using mp3gain (Db WHAT?)

> 
> I've always been a little puzzled by how RMS is expressed 
> anyway. For instance, SoundForge expresses RMS as a negative 
> number, with 0 being the theoretical maximum loudness. A 
> track that MP3Gain lists as having an RMS of 94 might equate 
> to an RMS value of -16.5 db in SoundForge.
> 

Many things that report loudness in dB are sloppy about exactly WHAT
they're reporting.  Decibels is, after all, just a measure of the
relationship of one value to another.  So, are we talking dBv, dBm,
dBu???

When you see negative numbers, they usually reference Db relative to
"unity gain" -- In the digital world, this would mean a signal value of
all (binary) ones.  In VU terms, this is usually dBm (dB referenced to a
milliwatt, and OLD reference) that most typically refers to the signal
references to about 0.77 volts.  You'll also see dBu or dBv, which are
normally used to mean the same thing.

Peter