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<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">I know there have been threads on both of these topics but I’m not sure I understand the final advice or the driving policy</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri"> behind current practice.</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">First the 1.2.1 image has lots of different script files.</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">Some are .pl</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri"> and others are .sh.</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">There are even a few .py.</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">I know what they are but there are also lots of files that are BASH scripts but don’t have a .sh extension.</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">Why in some cases do they have</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri"> extensions and in others they don’t?</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">Should they all have extensions?</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">Next the old audio thing again.</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">The</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri"> asterisk sounds folder seems to have .gsm at 8khz 8 bit sampling.</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">Comments in several .sh files indicate that in order to use CAT you need to have all f</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">iles formatted the same.</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">That is obvious but no harm in pointing it out.</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">However the files for the shutdown and reboot scripts are 8kh</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">z 16 bit wave files.</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">They play just fine through the radio nodes.</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">In fact I’ve heard 11</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">025 16 bit audio play fine as well.</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">Yes I can hear the difference in audio quality even over the radio between 8 and 16 bit.</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">More so with higher sampling rates.</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">So for some questions.</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">Where is the 8khz 8 bit limit coming from?</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">Is it really a limit or just best practice?</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">Forgetting the space issue is there any reason not to use a 16 bit 8khz or even slightly higher format?</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">Would ulaw or even wav be a better option for audio under local control?</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">The saytime script has a line to adjust the volume of the final audio output.</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">The comment basically reads that negative numbers are lower and to see the sox man page for details.</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">The script had 1.35 as the value.</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">Changing it to -1.35 resulted in</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">audio distorted and to loud to be useful at all.</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">Going above 2.0</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">seemed to be an upper limit</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri">.</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">Finally 0.0 resulted in silence.</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">So I came to the conclusion that 0.0 to 2.0 was the effective working range of options.</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">Is this some kind of multiplying factor based on original audio level?</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">I typically normalize audio to peak -1.5DB.</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">I do that before placing audio in the sound libraries.</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">Would it be better to just normalize to something lower</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri"> to keep audio in line with other sources of TX audio?</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">For audio outside my control would it be better to use a</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">sox process to normalize to the rest of my library?</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">What about just using sox to always normalize anything going out</FONT></SPAN><SPAN LANG="en-us"><FONT FACE="Calibri"> or is the volume change method in the script the best approach?</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">Any thoughts</FONT></SPAN><SPAN LANG="en-us"> <FONT FACE="Calibri">on these issues would be appreciated.</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"><FONT FACE="Calibri">73</FONT></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"></SPAN></P>
<P DIR=LTR><SPAN LANG="en-us"></SPAN></P>
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