diff --git a/12.tidal b/12.tidal
new file mode 100644
index 0000000..9fc4f9f
--- /dev/null
+++ b/12.tidal
@@ -0,0 +1,12 @@
+d1
+	$n "d4 d5 g4 d5 a4 d5 a5"
+	#s "midi"
+
+d2
+	$n "g5 ~ a5 d6"
+	#s "midi"
+
+d3
+	$chop "<4 8 16>"
+	$n "a5*2"
+	#s "midi"
diff --git a/13.tidal b/13.tidal
new file mode 100644
index 0000000..36520e9
--- /dev/null
+++ b/13.tidal
@@ -0,0 +1,12 @@
+d1
+	$n "gs g gf cs"
+	#s "midi"
+
+d2
+	$chop "15"
+	$ stack [
+		s "dr2*2 ~",
+		s "dr2:4",
+		s "dr2:9*2",
+		s "~ sd*4 sd*8"
+	]