[BC] Audio levels

[Richard Fry]

>To those experienced in the art and science of broadcast and telephony, dBm 
>has a well-understood meaning, the SI-unit committees in France be damned.
__________

To this poster, and others responding to my comments on this topic...

Each of us is entitled to a personal opinion, and no problem there.

However the official position of the National Institute of Standards and 
Technology (NIST) in the US supports/requires the use in the US of standard 
SI definitions (see http://physics.nist.gov/Pubs/SP811/sec02.html ).

Here is a partial quote from this source, from this URL: 
http://physics.nist.gov/Pubs/SP811/sec02.html .  Note that the Code of 
Federal Regulations includes those regulations applying to AM/FM/TV 
broadcast operations.

\\ Policy on the Use of the SI

In accordance with various Federal Acts, the Code of Federal Regulations, 
and Executive Order 12770 (see Preface), it is NIST policy that the SI shall 
be used in all NIST publications. (Footnote 1) When the field of application 
or the special needs of users of NIST publications require the use of other 
units, the values of quantities shall first be expressed in acceptable 
units, where it is to be understood that acceptable units include the units 
of the SI and those units recognized for use with the SI; the corresponding 
values expressed in the other units shall then follow in parentheses. (For 
precise definitions of the terms "units of the SI" and "acceptable units" as 
used in this Guide, see Sec. 5.4). Exceptions to this policy require the 
prior approval of the NIST Director. The following three sections - 2.1 
Essential data, 2.1.1 Tables and graphs, and 2.2 Descriptive information - 
elaborate upon this policy.

2.1 Essential data

Essential data express or interpret quantitative results. All such data 
shall be given in acceptable units. In those cases where the sole use of 
acceptable units would compromise good communication, or units other than 
acceptable units have been specified as a contractual requirement, values of 
quantities shall be given in acceptable units followed, in parentheses, by 
the values of the same quantities given in the other units.

Exceptions may sometimes be necessary for commercial devices, technical 
standards, or quantities having special legal significance; examples include 
commercial weights and measures devices and the related laws and 
regulations. However, even in such cases, values of quantities expressed in 
acceptable units should be used when possible with the same values expressed 
in other units following in parentheses. // ...

RF