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<p><font size="5">Hi, Pro audio! Happy Holidays from Bob.<br>
</font></p>
<p><font size="5">Naturally, I started a firestorm on facebook
asking a question about grounding in a headphone amplifier I'm
building. <br>
</font></p>
<p><font size="5">I made a mistake by forgetting to show the
connection between the 0 volt (transformer center tap) and
chassic ground... oops, so the conversation went downhill and
even after I revised my diagram some people were responding to
my first diagram with the error :-(<br>
</font></p>
<p><font size="5">I insisted (and still insist) that EMI/RFI
interference at the audio input is ameliorrated in Muncy's "rule
2": by connecting pin 1 to chassis directly at the audio input.
</font><font size="5">This is the centerpiece of Muncy's seminal
article "Noise Susceptibility in Analog and Digital Signal
Processing Systems"<br>
</font>
</p>
<p><font size="5">I know this from experience as well as theory,
having successfully installed a microphone preamplifier on the
101st floor of the World Trade Center in 1995 or so. <br>
</font></p>
<p><font size="5">Now on Facebook, a genuine expert in power supply
regulation design said "that will make the regulator unstable
cause it sees every ground current as an error".</font></p>
<p><font size="5">I'm not expert enough to either verify or refute
the above statement, but perhaps my response to his statement
could be to recommend connecting pin 1 to chassis through a
capacitor. <br>
</font></p>
<p><font size="5">Would the experts on this group please comment on
these thoughts? Thanks.</font></p>
<p><font size="5">I think that this reflector does not permit
attachments, so here is a link to my simple block diagram, which
is essentially a simplification of Muncy's Figure 1 in his paper
if you'd like to refer to the diagram:<br>
</font></p>
<p><font size="5"><a class="moz-txt-link-freetext" href="https://crush.digido.com/?u=pro_audio&p=muncy">https://crush.digido.com/?u=pro_audio&p=muncy</a><br>
</font></p>
<p><font size="5"><br>
</font></p>
<p><font size="5">Thanks in advance,</font></p>
<p><font size="5"><br>
</font></p>
<p><font size="5">Bob</font></p>
<br>
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<div class="moz-signature">-- <br>
<pre><font class="3D""" face="3D"Courier"">
If you want good sound on your album, come to
Bob Katz 407-831-0233 DIGITAL DOMAIN MASTERING STUDIO
Author: <b>Mastering Audio</b>
<a href="https://www.digido.com/">Digital Domain Website</a>
No trees were killed in the sending of this message. However a large number
of electrons were terribly inconvenienced.</font>
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