Re: free Orban loudness meter app now available

In article <4801bab5.350759390@[EMAIL PROTECTED]
>, 
nospam@[EMAIL PROTECTED]
 says...
>
>
>On Sat, 12 Apr 2008 23:38:59 -0800, Robert Orban
><donotreply@[EMAIL PROTECTED]
> wrote:
>
>>>OK. here is what I get.
>>>
>>>Generate a tone at -18dB in Audition, and it shows -14dB on 
both 
>>VU
>>>and PPM, with VU gain set to 10dB. Is that what you would 
expect?
>>
>>I would expect a sinewave peaking at 0 dBfs to indicate 0 on the 
>>loudness meter's PPM and absolute peak meter. I would also 
expect 
>>the VU meter to read 0 dB when its gain is set for +10 dB. Because 
>>this is admittedly confusing, the next release will be modified so 
that 
>>when the VU gain is set to 0 dB, the VU meter agrees with the 
>>PPM and absolute peak when fed with a sinewave.
>
>No, I definitely see a 4dB discrepancy between peak sine wave 
level
>and the indications on PPM and VU (+10). The meters read higher 
than
>the actual signal level. The sound card is an M-Audio Audiophile 
2496
>if that is any help.
>
>See this screen shot for the situation  CBS loudness gain is +18, VU
>meter gain is +10.
>
>http://81.174.169.10/odds/orbanppm.gif

I will investigate this.

My first guess is that the 4 dB you are seeing is actually 3.922 dB [20 
log10 (2/pi)], which is the difference between the peak and average 
value of a sinewave. If I recall correctly, Audition allows you to scale 
levels according to the peak or average value of a sinewave, so this 
is what I would investigate.