diff --git a/papers/format.md b/papers/format.md
index 1a8cd7219..5dd7d206a 100644
--- a/papers/format.md
+++ b/papers/format.md
@@ -32,6 +32,7 @@ these fields are 0 in format versions prior to 100 (0.6pre1).
 
 the format versions are:
 
+- 107: Furnace dev107
 - 106: Furnace dev106
 - 105: Furnace dev105
 - 104: Furnace dev104
@@ -850,6 +851,21 @@ size | description
  --- | **Game Boy extra flags** (>=106)
   1  | use software envelope
   1  | always init hard env on new note
+ --- | **ES5506 data** (>=107)
+  1  | filter mode
+     | - 0: HPK2_HPK2
+     | - 1: HPK2_LPK1
+     | - 2: LPK2_LPK2
+     | - 3: LPK2_LPK1
+  2  | K1
+  2  | K2
+  2  | envelope count
+  1  | left volume ramp
+  1  | right volume ramp
+  1  | K1 ramp
+  1  | K2 ramp
+  1  | K1 slow
+  1  | K2 slow
 ```
 
 # wavetable
diff --git a/src/engine/engine.h b/src/engine/engine.h
index 191414f5f..8e2c094da 100644
--- a/src/engine/engine.h
+++ b/src/engine/engine.h
@@ -46,8 +46,8 @@
 #define BUSY_BEGIN_SOFT softLocked=true; isBusy.lock();
 #define BUSY_END isBusy.unlock(); softLocked=false;
 
-#define DIV_VERSION "dev106"
-#define DIV_ENGINE_VERSION 106
+#define DIV_VERSION "dev107"
+#define DIV_ENGINE_VERSION 107
 
 // for imports
 #define DIV_VERSION_MOD 0xff01
diff --git a/src/engine/instrument.cpp b/src/engine/instrument.cpp
index 2836e6f95..1720bf56a 100644
--- a/src/engine/instrument.cpp
+++ b/src/engine/instrument.cpp
@@ -543,6 +543,18 @@ void DivInstrument::putInsData(SafeWriter* w) {
   w->writeC(gb.softEnv);
   w->writeC(gb.alwaysInit);
 
+  // ES5506
+  w->writeC(es5506.filter.mode);
+  w->writeS(es5506.filter.k1);
+  w->writeS(es5506.filter.k2);
+  w->writeS(es5506.envelope.ecount);
+  w->writeC(es5506.envelope.lVRamp);
+  w->writeC(es5506.envelope.rVRamp);
+  w->writeC(es5506.envelope.k1Ramp);
+  w->writeC(es5506.envelope.k2Ramp);
+  w->writeC(es5506.envelope.k1Slow);
+  w->writeC(es5506.envelope.k2Slow);
+
   blockEndSeek=w->tell();
   w->seek(blockStartSeek,SEEK_SET);
   w->writeI(blockEndSeek-blockStartSeek-4);
@@ -1111,6 +1123,20 @@ DivDataErrors DivInstrument::readInsData(SafeReader& reader, short version) {
     gb.alwaysInit=reader.readC();
   }
 
+  // ES5506
+  if (version>=107) {
+    es5506.filter.mode=(DivInstrumentES5506::Filter::FilterMode)reader.readC();
+    es5506.filter.k1=reader.readS();
+    es5506.filter.k2=reader.readS();
+    es5506.envelope.ecount=reader.readS();
+    es5506.envelope.lVRamp=reader.readC();
+    es5506.envelope.rVRamp=reader.readC();
+    es5506.envelope.k1Ramp=reader.readC();
+    es5506.envelope.k2Ramp=reader.readC();
+    es5506.envelope.k1Slow=reader.readC();
+    es5506.envelope.k2Slow=reader.readC();
+  }
+
   return DIV_DATA_SUCCESS;
 }
 
diff --git a/src/engine/instrument.h b/src/engine/instrument.h
index cfbed65a3..d3df4b631 100644
--- a/src/engine/instrument.h
+++ b/src/engine/instrument.h
@@ -468,7 +468,7 @@ struct DivInstrumentSoundUnit {
 struct DivInstrumentES5506 {
   struct Filter {
     enum FilterMode: unsigned char { // filter mode for pole 4,3
-      FILTER_MODE_HPK2_HPK2,
+      FILTER_MODE_HPK2_HPK2=0,
       FILTER_MODE_HPK2_LPK1,
       FILTER_MODE_LPK2_LPK2,
       FILTER_MODE_LPK2_LPK1,
@@ -494,12 +494,9 @@ struct DivInstrumentES5506 {
       k1Slow(false),
       k2Slow(false) {}
   };
-  signed int lVol, rVol;
   Filter filter;
   Envelope envelope;
-  DivInstrumentES5506():
-    lVol(0xffff),
-    rVol(0xffff) {}
+  DivInstrumentES5506() {}
 };
 
 struct DivInstrument {