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</o:shapelayout></xml><![endif]--></head><body lang=EN-US link=blue vlink=purple style='word-wrap:break-word'><div class=WordSection1><p class=MsoNormal><span style='font-size:14.0pt'>The Problem Of The Month this month was how to lower the volume on a childs toy.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt'>The speaker is driven from two pins of the processor. The DC resistance of the speaker is 9.3 Ohms.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt'>Several suggestions were made on how to reduce the volume. I will report here on the first few things I tried.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt'>I downloaded an app on my iPhone to measure loudness.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt'>The app was very specific in stating that the values measured were approximate.<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt'><o:p> </o:p></span></p><table class=MsoNormalTable border=0 cellspacing=0 cellpadding=0 width=515 style='width:386.0pt;margin-left:-.15pt;border-collapse:collapse'><tr style='height:14.25pt'><td width=227 nowrap valign=bottom style='width:170.0pt;border:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'> <o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border:solid windowtext 1.0pt;border-left:none;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>LAeq<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border:solid windowtext 1.0pt;border-left:none;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>Max<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border:solid windowtext 1.0pt;border-left:none;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>LCPeak<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border:solid windowtext 1.0pt;border-left:none;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>TWA<o:p></o:p></span></p></td></tr><tr style='height:14.25pt'><td width=227 nowrap valign=bottom style='width:170.0pt;border:solid windowtext 1.0pt;border-top:none;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>unmodified<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>85.90<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>91.20<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>102.40<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>52.00<o:p></o:p></span></p></td></tr><tr style='height:14.25pt'><td width=227 nowrap valign=bottom style='width:170.0pt;border:solid windowtext 1.0pt;border-top:none;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>22 ohm in series<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>80.00<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>86.60<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>96.60<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>46.20<o:p></o:p></span></p></td></tr><tr style='height:14.25pt'><td width=227 nowrap valign=bottom style='width:170.0pt;border:solid windowtext 1.0pt;border-top:none;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>47 ohm in series<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>74.00<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>80.70<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>90.80<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal align=center style='text-align:center'><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>xxx<o:p></o:p></span></p></td></tr><tr style='height:14.25pt'><td width=227 nowrap valign=bottom style='width:170.0pt;border:solid windowtext 1.0pt;border-top:none;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>47 uf in series<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>87.70<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>93.50<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>104.20<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>55.30<o:p></o:p></span></p></td></tr><tr style='height:14.25pt'><td width=227 nowrap valign=bottom style='width:170.0pt;border:solid windowtext 1.0pt;border-top:none;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>1 uf in series<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>76.30<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>83.10<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal align=right style='text-align:right'><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>95.40<o:p></o:p></span></p></td><td width=72 nowrap valign=bottom style='width:.75in;border-top:none;border-left:none;border-bottom:solid windowtext 1.0pt;border-right:solid windowtext 1.0pt;padding:0in 5.4pt 0in 5.4pt;height:14.25pt'><p class=MsoNormal align=center style='text-align:center'><span style='font-family:"Arial",sans-serif;color:black;mso-ligatures:none'>xxx<o:p></o:p></span></p></td></tr></table><p class=MsoNormal><span style='font-size:14.0pt'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt'>To my untrained ear, I found the 1 uf to be a good result. I did not notice a change in the tonal qualities, but I am untrained and old (so I don’t hear high frequencies).<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt'><o:p> </o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt'>---> Paul<o:p></o:p></span></p><p class=MsoNormal><span style='font-size:14.0pt'><o:p> </o:p></span></p></div></body></html>