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<span style="font-size: 14pt; font-family: Arial, sans-serif;"><a style=""><span style="background: rgb(250, 250, 250);"><font color="#ff0000"> </font></span><span style="color: black; background: rgb(250, 250, 250);"> </span></a><o:p style="color: rgb(0, 0, 0);"> </o:p></span></p>
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<span style="font-size:14.0pt;font-family:"Arial",sans-serif">LF Tinnitus ???<o:p> </o:p></span></p>
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<span style="font-size:14.0pt;font-family:"Arial",sans-serif">Since the subject of “ordinary tinnitus” (HF; say 5 kHz – 10 kHz) has appeared here as a topic, please humor me in allowing mention of the “World-Wide Hum” (WWH, sometimes Taos Hum, etc.) which is
a mysterious LF hum (like an idling diesel engine in the distance - perhaps 30 Hz to 100Hz – I hear 64 Hz), often 24/7/365, the exact nature and cause of which is largely unknown.<o:p> </o:p></span></p>
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<span style="font-size:14.0pt;font-family:"Arial",sans-serif">Few people hear this (perhaps 2%), but observations are confounded by real trucks, refrigerator units, failing power transformers, etc., as well as (conspiracy directed) entertaining suggestions
of government mind-control or underground invasion tunnel drilling, cell towers, etc.
<span style="mso-spacerun:yes"> </span>Few good audio engineers are hearers and participating investigators.
<span style="mso-spacerun:yes"> </span><o:p> </o:p></span></p>
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<span style="font-size:14.0pt;font-family:"Arial",sans-serif">This Hum is likely an individually generated (internal) artifact – not a real physical sound; a LF tinnitus.<span style="mso-spacerun:yes">
</span>Importantly and diagnostically, various “impulsive” INDIVIDUAL ACTIONS (vigorous head-shake, exhale, grunt) seem to interrupt the WWH for about ˝ a second, after which it is found to have ramped back up.<span style="mso-spacerun:yes">
</span>This ramp-back-up timing reminds an audio engineer of AGC, which in turn might suggest actions of protective muscles in the middle ear (supposition here).
<o:p> </o:p></span></p>
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<span style="font-size:14.0pt;font-family:"Arial",sans-serif"><o:p> </o:p></span></p>
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<span style="font-size:14.0pt;font-family:"Arial",sans-serif">For those interested, Dr. Glen MacPherson maintains an excellent website on the WWH:<o:p> </o:p></span></p>
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<span style="font-size:14.0pt;font-family:"Arial",sans-serif"><a href="https://hummap.wordpress.com/">https://hummap.wordpress.com/</a><o:p> </o:p></span></p>
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<span style="font-size:14.0pt;font-family:"Arial",sans-serif">and I have posted on my EN site Webnotes linked here:<o:p> </o:p></span></p>
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<span style="font-size:14.0pt;font-family:"Arial",sans-serif"><a href="http://electronotes.netfirms.com/ENWN56.pdf">http://electronotes.netfirms.com/ENWN56.pdf</a><o:p> </o:p></span></p>
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<span style="font-size:14.0pt;font-family:"Arial",sans-serif"><o:p> </o:p></span></p>
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<span style="font-size:14.0pt;font-family:"Arial",sans-serif">-<b>Bernie</b></span><b><span style="font-size:20.0pt"><o:p> </o:p></span></b></p>
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