diff --git a/src/WavWriter/WavWriter.cpp b/src/WavWriter/WavWriter.cpp
new file mode 100644
index 0000000..3a06c9f
--- /dev/null
+++ b/src/WavWriter/WavWriter.cpp
@@ -0,0 +1,69 @@
+/*
+ * Filename:    WavWriter.cpp
+ *
+ * Description:
+ *
+ *
+ * Version:     
+ * Created:     Mon Mar  9 19:31:28 2020
+ * Revision:    None
+ * Author:      Rachel Fae Fox (foxiepaws),fox@foxiepa.ws
+ *
+ */
+#include "WavWriter.h"
+#include <cstdarg>
+
+WavWriter::WavWriter(char* filename, uint srate, uint chan, uint bps) {
+    file = fopen(filename, "w");
+    sr = srate;
+    ch = chan;
+    bd = bps;
+    length = 0; 
+    byterate = sr * ch * (bd/8);
+    blockalign = ch * (bd/8); 
+    
+    // initialise the first 40 bytes for the header later.
+    for (int x = 0; x < 40; x++) {
+	fputc(0x00,file);
+    }
+}
+void WavWriter::writeHeader() {
+    rewind(file);
+    fprintf(file,"RIFF");
+    writeBytes((char*) &riffsize,4);
+    fprintf(file,"WAVEfmt ");
+    writeBytes((char*) &fmtsize,4);
+    writeBytes((char*) &type,2);
+    writeBytes((char*) &ch,2);
+    writeBytes((char*) &sr,4);
+    writeBytes((char*) &byterate,4);
+    writeBytes((char*) &blockalign,2);
+    writeBytes((char*) &bd, 2);
+    fprintf(file,"data");
+    writeBytes((char*) &datasize, 4);
+}
+void WavWriter::finalise() {
+    datasize = length;
+    riffsize = 20 + fmtsize + datasize;
+    writeHeader();
+    fclose(file);
+}
+
+void WavWriter::write(...) {
+    va_list args;
+    va_start(args, ch);
+    for (int i=0;i < ch;i++) {
+	uint32_t v = va_arg(args,int);
+	writeBytes((char*) &v,(bd/8));
+    }
+    va_end(args);
+}
+
+void WavWriter::writeBytes(char* bytes, uint count) {
+    for (int i = 0; i < count ; i++) {
+	length++;
+	putc(bytes[i],file);
+    }
+}
+
+WavWriter::~WavWriter(){}
diff --git a/src/WavWriter/WavWriter.h b/src/WavWriter/WavWriter.h
new file mode 100644
index 0000000..97c6f4d
--- /dev/null
+++ b/src/WavWriter/WavWriter.h
@@ -0,0 +1,63 @@
+/*
+ * Filename:    WavWriter.h
+ *
+ * Description:
+ *
+ *
+ * Version:     
+ * Created:     Mon Mar  9 18:00:11 2020
+ * Revision:    None
+ * Author:      Rachel Fae Fox (foxiepaws),fox@foxiepa.ws
+ *
+ */
+#include <cstdint>
+#include <cstdio>
+
+// standard wave files have a 32bit size limit.
+#define WAVMAX (0xffffff - 20)
+
+typedef unsigned int uint;
+class WavWriter {
+
+    uint32_t length = 0; 
+    uint32_t sr; // sample rate (gstool(samplerate))
+    uint16_t bd; // bit depth   (gstool(bitdepth))
+    uint16_t ch; // channels    (gstool(channels))
+    uint32_t datasize;
+    uint32_t fmtsize = 16;
+    uint16_t type = 1;
+    uint32_t riffsize;
+    uint32_t byterate;
+    uint16_t blockalign;
+    FILE* file;
+    
+    // helpers
+    bool fit() { return (WAVMAX-fmtsize) > (length + byterate); } // see if one more sample will fit
+    void writeBytes(char* bytes, uint count);
+    
+ public:
+    // gstool
+    /* BEGIN GSTOOL GENERATED BLOCK */
+    // getters
+    uint32_t samplerate() { return sr; }
+    uint16_t bitdepth() { return bd; }
+    uint16_t channels() { return ch; }
+    // setters
+    void samplerate(uint32_t v) { sr = v; }
+    void bitdepth(uint16_t v) { bd = v; }
+    void channels(uint16_t v) { ch = v; }
+    /* END GSTOOL GENERATED BLOCK */ 
+
+    WavWriter() {}
+    ~WavWriter();
+    WavWriter(char* filename, uint srate, uint chan, uint bps);
+    void finalise();
+    void writeHeader();
+    void write(...); 
+};
+
+
+/* Local Variables: */
+/* mode: c++ */
+/* flycheck-clang-language-standard: "c++11" */
+/* End: */
diff --git a/src/wavtest.cpp b/src/wavtest.cpp
new file mode 100644
index 0000000..ad7cb68
--- /dev/null
+++ b/src/wavtest.cpp
@@ -0,0 +1,51 @@
+/*
+ * Filename:    wavtest.cpp
+ *
+ * Description:
+ *
+ *
+ * Version:     
+ * Created:     Mon Mar  9 23:06:08 2020
+ * Revision:    None
+ * Author:      Rachel Fae Fox (foxiepaws),fox@foxiepa.ws
+ *
+ */
+
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <math.h>
+#include "FM/Engine.h"
+#include "WavWriter/WavWriter.h"
+
+int16_t toint16(double i) {
+    double temp = i *= 32767;
+    return floor(temp);
+}
+int main(int argc, char** argv){
+    FM::Engine<2> *f = new FM::Engine<2>();
+    f->getOperator(0)->setAll(2.0,0.0,0.0);
+    f->getOperator(0)->getEnvelope()->setAttackTime(1.0);
+    f->getOperator(0)->getEnvelope()->setDecayTime(0.5);
+    f->getOperator(0)->getEnvelope()->setMaxLevel(1.0);
+    f->getOperator(0)->getEnvelope()->setModMode(true); // play until reset.
+    f->getOperator(1)->getEnvelope()->setReleaseTime(2.5); 
+    f->getOperator(1)->setAll(1.0,0.0,0.0);
+    f->setGainMatrix(0,0,0.0); // op1 fbl    = 0
+    f->setGainMatrix(0,1,1.0); // op1 -> op2 = 1
+    f->setGainMatrix(1,0,0.0); // op2 -> op1 = 0
+    f->setGainMatrix(1,2,1.0); // op2 -> out = 1
+    f->freq = 440;
+    f->gate = true;
+    double   seconds    = 20;
+    // init a new writer
+    WavWriter *w = new WavWriter("wavtest.wav",44100,2,16);
+    for (int s = 0; s < 44100*seconds; s++) {
+	std::pair<double,double> st = (*f)();
+	w->write(toint16(st.first/4.0), toint16(st.second/4.0));
+    }
+    w->finalise();
+    return 0;
+}
+
+