diff --git a/Measurer.cpp b/Measurer.cpp
index 154b0df..3e00e23 100644
--- a/Measurer.cpp
+++ b/Measurer.cpp
@@ -9,12 +9,14 @@
 #include <qendian.h>
 
 #include <vector>
+#include <iostream>
+#include <sstream>
 #include <unistd.h>
 
 using namespace std;
 
-Measurer::Measurer(QAudioDeviceInfo input, QAudioDeviceInfo output, MeasureChannel channel)
-    : input(input), output(output), channel(channel)
+Measurer::Measurer(QAudioDeviceInfo input, QAudioDeviceInfo output, MeasureChannel channel, bool debug)
+    : input(input), output(output), channel(channel), debug(debug)
 {
 }
 
@@ -72,6 +74,15 @@ float Measurer::ProcessData(QByteArray data)
 		int t = qFromLittleEndian<qint16>(data.data() + i);
 		samples.push_back(t / 32767.0);
 	}
+	if (debug)
+	{
+		ostringstream oss;
+		for (int i = 0; i < (int)samples.size(); i++)
+		{
+			oss << samples[i] << " ";
+		}
+		cerr << "Samples read: " << oss.str() << "\n";
+	}
 	// cut off starting and ending silence
 	int left_pos = 0;
 	while (left_pos < (int)samples.size() && abs(samples[left_pos]) < 1e-4) left_pos++;
@@ -102,6 +113,11 @@ float Measurer::ProcessData(QByteArray data)
 		}
 	}
 	float desired = TONE_FREQUENCY * pow / SAMPLE_RATE;
+	if (debug)
+	{
+		cerr << "Measure: desired = " << desired << " argmax = " << argmax << " max = " 
+		     << max << " left_pos = " << left_pos << " right_pos = " << right_pos << "\n";
+	}
 	if (abs(desired - argmax) < 1e-3)
 	{
 		return max / pow;
diff --git a/Measurer.h b/Measurer.h
index 341a7c3..461e152 100644
--- a/Measurer.h
+++ b/Measurer.h
@@ -16,10 +16,11 @@ class Measurer
 
 	MeasureChannel channel;
 	QAudioDeviceInfo input, output;
+	bool debug;
 
 	float ProcessData(QByteArray data);
 public:
-	Measurer(QAudioDeviceInfo input, QAudioDeviceInfo output, MeasureChannel channel);
+	Measurer(QAudioDeviceInfo input, QAudioDeviceInfo output, MeasureChannel channel, bool debug);
 	float Measure(float duration);
 };
 
diff --git a/main.cpp b/main.cpp
index fc26698..291efc5 100644
--- a/main.cpp
+++ b/main.cpp
@@ -49,19 +49,27 @@ QAudioDeviceInfo GetOutputDevice(QString name)
 	throw (string)("Unable to find device " + name.toStdString());
 }
 
-void Measure(QString input_device_name, QString output_device_name, float duration)
+void Measure(QString input_device_name, QString output_device_name, float duration, bool debug)
 {
 	auto input = GetInputDevice(input_device_name);
 	auto output = GetOutputDevice(output_device_name);
-	Measurer left(input, output, MeasureChannel::Left);
+	Measurer left(input, output, MeasureChannel::Left, debug);
 	float left_result = left.Measure(duration);
-	Measurer right(input, output, MeasureChannel::Right);
+	Measurer right(input, output, MeasureChannel::Right, debug);
 	float right_result = right.Measure(duration);
+	if (debug)
+	{
+		cerr << "Measure complete, left_result = " << left_result << " right_result = " << right_result << "\n";
+	}
 	float k = 2 * right_result;
 	float v0v = left_result / k;
 	// assume r2 = 10K
 	float r1 = 10000 / v0v - 10000;
 	float t = 1.0 / (log(r1 / 10000) / 4300 + 1 / 298.0) - 273.0;
+	if (debug)
+	{
+	  cerr << "v0v = " << v0v << " r1 = " << r1 << " t = " << t << "\n";
+	}
 	cout.setf(ios::fixed | ios::showpoint);
 	cout.precision(4);
 	cout << t << "\n";
@@ -94,9 +102,11 @@ int main(int argc, char *argv[])
 		QCommandLineOption input_option(QStringList() << "i" << "input", "Name of device to receive input from", "input");
 		QCommandLineOption output_option(QStringList() << "o" << "output", "Name of device to send output to", "output");
 		QCommandLineOption duration_option(QStringList() << "d" << "duration", "How many seconds to record (uses twice this time)", "duration");
+		QCommandLineOption debug_option("debug", "Turn on additional logging");
 		parser.addOption(input_option);
 		parser.addOption(output_option);
 		parser.addOption(duration_option);
+		parser.addOption(debug_option);
 		parser.process(a);
 		if (!parser.isSet(input_option))
 		{
@@ -115,7 +125,9 @@ int main(int argc, char *argv[])
 		{
 			duration = parser.value(duration_option).toFloat();
 		}
-		Measure(input_device_name, output_device_name, duration);
+		bool debug = false;
+		if (parser.isSet(debug_option)) debug = true;
+		Measure(input_device_name, output_device_name, duration, debug);
 		return 0;
 	}
 	else
@@ -123,5 +135,5 @@ int main(int argc, char *argv[])
 		parser.process(a);
 		parser.showHelp(0);
 	}
-	return a.exec();
+	return 0;
 }