my $last_k = 'NIL';
my $last_n = 'NIL';
foreach my $c (sort @chords) {
  (my $k, my $n) = split(/;/, $c);
  if ($last_k eq $k) {
    if ($last_n ne $n) {
      my $out = sprintf("Two names: '%-16s', '%-16s' for ", $last_n, $n);
      print $out . "        " . &notenames($k) . "\n";
      $duplicates++;
    } 
  }
  ($last_k, $last_n) = ($k, $n);
}
print "$duplicates multiple chord names\n";