diff --git a/dist/hornverifier b/dist/hornverifier
index ff0b173c..e5a4f859 100755
Binary files a/dist/hornverifier and b/dist/hornverifier differ
diff --git a/dist/roverd b/dist/roverd
index 891b1c45..1efe4b4a 100755
Binary files a/dist/roverd and b/dist/roverd differ
diff --git a/dist/servoverifier b/dist/servoverifier
index 35426b97..71f6a841 100755
Binary files a/dist/servoverifier and b/dist/servoverifier differ
diff --git a/pi/roverd/cmd/hornverifier/main.go b/pi/roverd/cmd/hornverifier/main.go
index 32e0bd06..a9f45802 100644
--- a/pi/roverd/cmd/hornverifier/main.go
+++ b/pi/roverd/cmd/hornverifier/main.go
@@ -144,7 +144,7 @@ func synthChord(writer *bufio.Writer, freqs []float64, rate, channels int, durat
 			env := envelope(sampleIndex, attackFrames, steadyFrames, releaseFrames)
 			sample := 0.0
 			for j := range freqs {
-				sample += math.Sin(phase[j])
+				sample += sawFromPhase(phase[j])
 				phase[j] += increment[j]
 				if phase[j] > twoPi {
 					phase[j] -= twoPi
@@ -181,3 +181,7 @@ func envelope(sampleIndex, attackFrames, steadyFrames, releaseFrames int) float6
 	}
 	return 1.0
 }
+
+func sawFromPhase(phase float64) float64 {
+	return 2.0*(phase/twoPi) - 1.0
+}