diff --git a/VERSION b/VERSION
index f385eef..649a0ca 100644
--- a/VERSION
+++ b/VERSION
@@ -1,2 +1,2 @@
-2021 November 25 2021
+2021 December 10 2021
 
diff --git a/doc/CHANGES b/doc/CHANGES
index b44add9..f9f9329 100644
--- a/doc/CHANGES
+++ b/doc/CHANGES
@@ -14491,3 +14491,45 @@ with
 if (*nnotes > 0) { /* [SS] 2021-11-25 */
 in the function make_note_representation(...)
 
+
+December 05 2021
+
+abc2midi new feature. Abc2midi did not recognize double flats or double sharps
+in the gchord. For example
+
+X:1
+T: Double flat gchord
+M: 4/4
+L: 1/4
+K: C
+"Dbb" C4| C4 |
+
+returns the error message
+Error in line-char 6-0 : Unrecognized chord name "b"
+(Hint: use %MIDI chordname to define it. eg %MIDI chordname sus4 0 4 7).
+
+Fix: in event_handle_gchord in store.c, now check for a double accidental.
+
+
+December 10 2021
+
+abc2midi: introduced gchord elements k and K. A gchord string can
+contain and of the letters in zcfbghijkGHIJKx. Note that the chord
+elements j,J,k,K are only defined for gchords with 4 or 5 notes like
+M9 or M11. Here is a test example.
+
+X:1
+T: Gchord string
+M: 4/4
+L: 1/4
+K: C
+%%MIDI chordname x 0 3 5 7 9
+%%MIDI gchord fGHIJK
+"C11" C4 | C4 |
+"Cx"  C4 | C4|
+"C11/E" C4 | C4|
+"C11/G" C4 | C4|
+"C11/B" C4 | C4|
+
+
+
diff --git a/doc/readme.txt b/doc/readme.txt
index 40f869e..6c0ab82 100644
--- a/doc/readme.txt
+++ b/doc/readme.txt
@@ -1,7 +1,7 @@
 abcMIDI :   abc <-> MIDI conversion utilities
 
 midi2abc version 3.48 June 27 2021
-abc2midi version 4.61 October 11 2021
+abc2midi version 4.63 December 10 2021
 abc2abc  version 2.15 May 25 2021
 yaps     version 1.87 May 25 2021
 abcmatch version 1.80 November 25 2021
diff --git a/genmidi.c b/genmidi.c
index 24df6a1..941172b 100644
--- a/genmidi.c
+++ b/genmidi.c
@@ -398,7 +398,8 @@ char* s;
   p = s;
   j = 0;
   seq_len = 0;
-    while ((strchr("zcfbghijGHIJx", *p) != NULL) && (j <39)) {
+    /* [SS] 2021-12-10 */
+    while ((strchr("zcfbghijkGHIJKx", *p) != NULL) && (j <39)) {
     if (*p == 0) break;
     gchord_seq[j] = *p;
     p = p + 1;
@@ -2453,6 +2454,13 @@ int j;
         save_note(g_num*len, g_denom, gchordnotes[gchordnotes_size], 8192, gchord.chan, gchord.vel); 
       break;
 
+    /* [SS] 2021-12-10 */
+    case 'k':
+      if(gchordnotes_size >4 && g_started && gchords)
+        save_note(g_num*len, g_denom, gchordnotes[4], 8192, gchord.chan, gchord.vel); 
+      else /* [SS] 2016-01-03 */
+        save_note(g_num*len, g_denom, gchordnotes[gchordnotes_size], 8192, gchord.chan, gchord.vel); 
+
     case 'G':
       if(gchordnotes_size>0 && g_started && gchords)
         save_note(g_num*len, g_denom, gchordnotes[0]-12, 8192, gchord.chan, gchord.vel); 
@@ -2481,6 +2489,14 @@ int j;
         save_note(g_num*len, g_denom, gchordnotes[gchordnotes_size], 8192, gchord.chan, gchord.vel); 
       break;
 
+    /* [SS] 2021-12-10 */
+    case 'K':
+      if(gchordnotes_size >3 && g_started && gchords)
+        save_note(g_num*len, g_denom, gchordnotes[4]-12, 8192, gchord.chan, gchord.vel); 
+      else /* [SS] 2016-01-03 */
+        save_note(g_num*len, g_denom, gchordnotes[gchordnotes_size], 8192, gchord.chan, gchord.vel); 
+      break;
+
     case 'x':
       if(!gchord_error) {
          gchord_error++;
diff --git a/store.c b/store.c
index 0c85388..3a2d790 100644
--- a/store.c
+++ b/store.c
@@ -186,7 +186,7 @@ int main()
 
 */
 
-#define VERSION "4.61 October 11 2021 abc2midi" 
+#define VERSION "4.63 December 10 2021 abc2midi" 
 
 /* enables reading V: indication in header */
 #define XTEN1 1
@@ -4494,13 +4494,15 @@ void event_handle_gchord(s)
 char* s;
 {
   int basepitch;
-  char accidental, note;
+  char accidental, accidental2, note; /* [SS] 2021-12-05 */
   char* p;
   char name[9];
   int i;
   int chordno;
   int bassnote;
   int inversion;
+  int mult;  /* [SS] 2021-12-05 */
+  mult = 1;
 
   if (ignore_guitarchords == 1) return; /* [SS] 2019-12-09 */
   if ((*s >= '0') && (*s <= '5')) {
@@ -4527,7 +4529,9 @@ char* s;
     };
   };
   p = get_accidental(p, &accidental);
-  basepitch = pitchof(note, accidental, 1, 0, 0) - middle_c;
+  p = get_accidental(p, &accidental2); /* [SS] 2021-12-05 */
+  if (accidental2 != '=') mult = 2;  /* [SS] 2021-12-05 */
+  basepitch = pitchof(note, accidental, mult, 0, 0) - middle_c;
   i = 0;
   while ((i<9) && (*p != ' ') && (*p != '\0') && (*p != '(')
                && (*p != '/') && (*p != ')')) {
@@ -4543,12 +4547,16 @@ char* s;
       note = (int)*p - 'A' + 'a';
       p = p + 1;
       p = get_accidental(p, &accidental);
-      inversion = pitchof(note, accidental, 1, 0, 0) - middle_c;
+      p = get_accidental(p, &accidental2); /* [SS] 2021-12-05 */
+      if (accidental2 != '=') mult = 2;  /* [SS] 2021-12-05 */
+      inversion = pitchof(note, accidental, mult, 0, 0) - middle_c;
     } else if ((*p >= 'a') && (*p <= 'g')) {
       note = (int)*p;
       p = p + 1;
       p = get_accidental(p, &accidental);
-      inversion = pitchof(note, accidental, 1, 0, 0) - middle_c;
+      p = get_accidental(p, &accidental2); /* [SS] 2021-12-05 */
+      if (accidental2 != '=') mult = 2;  /* [SS] 2021-12-05 */
+      inversion = pitchof(note, accidental, mult, 0, 0) - middle_c;
     } else if (!silent) {
       event_error(" / must be followed by A-G or a-g in gchord");
     };