diff --git a/show/dance2012/subterms/song15.n3 b/show/dance2012/subterms/song15.n3
--- a/show/dance2012/subterms/song15.n3
+++ b/show/dance2012/subterms/song15.n3
@@ -1,26 +1,41 @@
-<http://light9.bigasterisk.com/show/dance2012/song15> <http://light9.bigasterisk.com/subterm> <http://light9.bigasterisk.com/show/dance2012/song15/subterm/front> .
-<http://light9.bigasterisk.com/show/dance2012/song15> <http://light9.bigasterisk.com/subterm> <http://light9.bigasterisk.com/show/dance2012/song15/subterm/song15start> .
-<http://light9.bigasterisk.com/show/dance2012/song15> <http://light9.bigasterisk.com/subterm> <http://light9.bigasterisk.com/show/dance2012/song15/subterm/strobe> .
-<http://light9.bigasterisk.com/show/dance2012/song15> <http://light9.bigasterisk.com/subterm> <http://light9.bigasterisk.com/show/dance2012/song15/subterm/chasecolors> .
-<http://light9.bigasterisk.com/show/dance2012/song15> <http://light9.bigasterisk.com/subterm> <http://light9.bigasterisk.com/show/dance2012/song15/subterm/center> .
-<http://light9.bigasterisk.com/show/dance2012/song15/subterm/strobe> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://light9.bigasterisk.com/Subterm> .
-<http://light9.bigasterisk.com/show/dance2012/song15/subterm/strobe> <http://www.w3.org/2000/01/rdf-schema#label> "strobe" .
-<http://light9.bigasterisk.com/show/dance2012/song15/subterm/strobe> <http://light9.bigasterisk.com/expression> "strobe(t)*chan(\"strobebright\")*(nsin(t*3)>.9)" .
-<http://light9.bigasterisk.com/show/dance2012/song15/subterm/strobe> <http://light9.bigasterisk.com/sub> <http://light9.bigasterisk.com/sub/strobe> .
+<http://light9.bigasterisk.com/show/dance2012/song15/subterm/center> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://light9.bigasterisk.com/Subterm> .
+<http://light9.bigasterisk.com/show/dance2012/song15/subterm/center> <http://www.w3.org/2000/01/rdf-schema#label> "center" .
+<http://light9.bigasterisk.com/show/dance2012/song15/subterm/center> <http://light9.bigasterisk.com/sub> <http://light9.bigasterisk.com/sub/center> .
+<http://light9.bigasterisk.com/show/dance2012/song15/subterm/center> <http://light9.bigasterisk.com/expression> "center(t)" .
 <http://light9.bigasterisk.com/show/dance2012/song15/subterm/chasecolors> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://light9.bigasterisk.com/Subterm> .
 <http://light9.bigasterisk.com/show/dance2012/song15/subterm/chasecolors> <http://www.w3.org/2000/01/rdf-schema#label> "chasecolors" .
+<http://light9.bigasterisk.com/show/dance2012/song15/subterm/chasecolors> <http://light9.bigasterisk.com/sub> <http://light9.bigasterisk.com/sub/chasecolors> .
 <http://light9.bigasterisk.com/show/dance2012/song15/subterm/chasecolors> <http://light9.bigasterisk.com/expression> "chase(t, names=colors, ontime=.3) * chasecolors(t)" .
-<http://light9.bigasterisk.com/show/dance2012/song15/subterm/chasecolors> <http://light9.bigasterisk.com/sub> <http://light9.bigasterisk.com/sub/chasecolors> .
+<http://light9.bigasterisk.com/show/dance2012/song15/subterm/stroberate> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://light9.bigasterisk.com/Subterm> .
+<http://light9.bigasterisk.com/show/dance2012/song15/subterm/stroberate> <http://www.w3.org/2000/01/rdf-schema#label> "stroberate" .
+<http://light9.bigasterisk.com/show/dance2012/song15/subterm/stroberate> <http://light9.bigasterisk.com/sub> <http://light9.bigasterisk.com/sub/stroberate> .
+<http://light9.bigasterisk.com/show/dance2012/song15/subterm/stroberate> <http://light9.bigasterisk.com/expression> "chan('strobespeed')*.97" .
+<http://light9.bigasterisk.com/show/dance2012/song15/subterm/strobe> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://light9.bigasterisk.com/Subterm> .
+<http://light9.bigasterisk.com/show/dance2012/song15/subterm/strobe> <http://www.w3.org/2000/01/rdf-schema#label> "strobe" .
+<http://light9.bigasterisk.com/show/dance2012/song15/subterm/strobe> <http://light9.bigasterisk.com/sub> <http://light9.bigasterisk.com/sub/strobe> .
+<http://light9.bigasterisk.com/show/dance2012/song15/subterm/strobe> <http://light9.bigasterisk.com/expression> "strobe(t)*chan(\"strobebright\")" .
+<http://light9.bigasterisk.com/show/dance2012/song15> <http://light9.bigasterisk.com/subterm> <http://light9.bigasterisk.com/show/dance2012/song15/subterm/center> .
+<http://light9.bigasterisk.com/show/dance2012/song15> <http://light9.bigasterisk.com/subterm> <http://light9.bigasterisk.com/show/dance2012/song15/subterm/chasecolors> .
+<http://light9.bigasterisk.com/show/dance2012/song15> <http://light9.bigasterisk.com/subterm> <http://light9.bigasterisk.com/show/dance2012/song15/subterm/stroberate> .
+<http://light9.bigasterisk.com/show/dance2012/song15> <http://light9.bigasterisk.com/subterm> <http://light9.bigasterisk.com/show/dance2012/song15/subterm/strobe> .
+<http://light9.bigasterisk.com/show/dance2012/song15> <http://light9.bigasterisk.com/subterm> <http://light9.bigasterisk.com/show/dance2012/song15/subterm/front> .
+<http://light9.bigasterisk.com/show/dance2012/song15> <http://light9.bigasterisk.com/subterm> <http://light9.bigasterisk.com/show/dance2012/song15/subterm/song15start> .
+<http://light9.bigasterisk.com/show/dance2012/song15> <http://light9.bigasterisk.com/subterm> <http://light9.bigasterisk.com/show/dance2012/song15/subterm/backctr> .
+<http://light9.bigasterisk.com/show/dance2012/song15> <http://light9.bigasterisk.com/subterm> <http://light9.bigasterisk.com/show/dance2012/song15/subterm/timewarp> .
 <http://light9.bigasterisk.com/show/dance2012/song15/subterm/front> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://light9.bigasterisk.com/Subterm> .
 <http://light9.bigasterisk.com/show/dance2012/song15/subterm/front> <http://www.w3.org/2000/01/rdf-schema#label> "front" .
+<http://light9.bigasterisk.com/show/dance2012/song15/subterm/front> <http://light9.bigasterisk.com/sub> <http://light9.bigasterisk.com/sub/front> .
 <http://light9.bigasterisk.com/show/dance2012/song15/subterm/front> <http://light9.bigasterisk.com/expression> "front(t)" .
-<http://light9.bigasterisk.com/show/dance2012/song15/subterm/front> <http://light9.bigasterisk.com/sub> <http://light9.bigasterisk.com/sub/front> .
 <http://light9.bigasterisk.com/show/dance2012/song15/subterm/song15start> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://light9.bigasterisk.com/Subterm> .
 <http://light9.bigasterisk.com/show/dance2012/song15/subterm/song15start> <http://www.w3.org/2000/01/rdf-schema#label> "song15start" .
+<http://light9.bigasterisk.com/show/dance2012/song15/subterm/song15start> <http://light9.bigasterisk.com/sub> <http://light9.bigasterisk.com/sub/song15start> .
 <http://light9.bigasterisk.com/show/dance2012/song15/subterm/song15start> <http://light9.bigasterisk.com/expression> "song15start(t)" .
-<http://light9.bigasterisk.com/show/dance2012/song15/subterm/song15start> <http://light9.bigasterisk.com/sub> <http://light9.bigasterisk.com/sub/song15start> .
-<http://light9.bigasterisk.com/show/dance2012/song15/subterm/center> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://light9.bigasterisk.com/Subterm> .
-<http://light9.bigasterisk.com/show/dance2012/song15/subterm/center> <http://www.w3.org/2000/01/rdf-schema#label> "center" .
-<http://light9.bigasterisk.com/show/dance2012/song15/subterm/center> <http://light9.bigasterisk.com/expression> "center(t)" .
-<http://light9.bigasterisk.com/show/dance2012/song15/subterm/center> <http://light9.bigasterisk.com/sub> <http://light9.bigasterisk.com/sub/center> .
+<http://light9.bigasterisk.com/show/dance2012/song15/subterm/backctr> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://light9.bigasterisk.com/Subterm> .
+<http://light9.bigasterisk.com/show/dance2012/song15/subterm/backctr> <http://www.w3.org/2000/01/rdf-schema#label> "backctr" .
+<http://light9.bigasterisk.com/show/dance2012/song15/subterm/backctr> <http://light9.bigasterisk.com/sub> <http://light9.bigasterisk.com/sub/backctr> .
+<http://light9.bigasterisk.com/show/dance2012/song15/subterm/backctr> <http://light9.bigasterisk.com/expression> "backctr(t)" .
+<http://light9.bigasterisk.com/show/dance2012/song15/subterm/timewarp> <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://light9.bigasterisk.com/Subterm> .
+<http://light9.bigasterisk.com/show/dance2012/song15/subterm/timewarp> <http://www.w3.org/2000/01/rdf-schema#label> "timewarp" .
+<http://light9.bigasterisk.com/show/dance2012/song15/subterm/timewarp> <http://light9.bigasterisk.com/sub> <http://light9.bigasterisk.com/sub/timewarp> .
+<http://light9.bigasterisk.com/show/dance2012/song15/subterm/timewarp> <http://light9.bigasterisk.com/expression> "chan('green')*(0 < timewarp(t) < 25) + chan('orange') * .5 * (.25 < timewarp(t) < .5) + chan('blue') * " .