replace in opening quotations

node122.html

@@ -78,7 +78,7 @@ Section <A HREF="node108.html#sect7.network">7.3</A>.
 Using a variable, non-recirculating comb filter we
 take out odd harmonics, leaving only the even ones, which
 sound an octave higher.  As before, the spectral envelope of the sound is
-roughly preserved by the operation, so we can avoid the ``chipmunk" effect we
+roughly preserved by the operation, so we can avoid the "chipmunk" effect we
 would have got by using speed change to do the transposition.
 
 <P>
@@ -86,7 +86,7 @@ would have got by using speed change to do the transposition.
 <DIV ALIGN="CENTER"><A NAME="fig07.29"></A><A NAME="8278"></A>
 <TABLE>
 <CAPTION ALIGN="BOTTOM"><STRONG>Figure 7.29:</STRONG>
-An ``octave doubler" uses pitch information (obtained using
+An "octave doubler" uses pitch information (obtained using
 a <TT>fiddle~</TT> object) to tune a comb filter to remove the odd harmonics
 in an incoming sound.</CAPTION>
 <TR><TD><IMG