[App_rpt-users] Echolink connection announcement Volume

[Ken]

> The audio was setup using the prescribed method, without the "MK-1
calibrated ear."
> If we raised the rx level, and reduced the tx level, then we'd have 
> difficulty hearing the station id. I suspect the level of our custom 
> recordings is too high, an I was trying to avoid the brute force method of
redoing each one.
>
> Thanks,
> Bob
> kk6ecm
>

Record level is tricky in Asterisk.  When seen on any editing program, "full
scale" is -6 dB f.s. or 0.5 on the voltage scale. I suspect the reason for
this is that uLaw only produces about 14 bits when converted to linear and
that is what asterisk expects for full scale.  (I guess losing those two
bits is equivalent to dividing by four or 6 dB down).  Have a look at some
of the Allison GSM files by importing them into Audacity and you will see
the max level is 0.5.  Even this is too loud for most people (as newbie
postings have indicated many times). I think a reasonable level is 3 dB down
from full scale - in other words, minus 9 dB relative to full scale (!) or
about 0.3 on the voltage scale.  

Ref: http://images.ohnosec.org/app-rpt-audacity.pdf

Regards
Ken
KE2N