replace in opening quotations

node38.html

@@ -101,7 +101,7 @@ samples and use seconds instead, converting to samples (and shifting by
 one) only just before the <TT>tabread4~</TT> object.
 The wavetable holds one second of sound, and we'll assume here that the
 nominal chunk size will not exceed 0.1 second, so that we can safely let
-the read point range from 0 to 0.9; the ``real" chunk size will vary, and
+the read point range from 0 to 0.9; the "real" chunk size will vary, and
 can become quite large, because of the moving read pointer.
 
 <P>
@@ -110,7 +110,7 @@ control sets the frequency of a phasor of amplitude 0.9, and therefore the
 precession must be multiplied by 0.9 to set the frequency of the phasor (so
 that, for a precession of one for instance, the amplitude and frequency of
 the read point are both 0.9, so that the slope, equal to amplitude over
-frequency, is one).  The output of this is named ``read-pt" as before, and
+frequency, is one).  The output of this is named "read-pt" as before, and
 is used by both copies of the wavetable reader.
 
 <P>