diff --git a/README.md b/README.md
index c88a39f..ddcc0a8 100644
--- a/README.md
+++ b/README.md
@@ -122,7 +122,10 @@ Some everyday helpers:
 * [probability density function](https://en.wikipedia.org/wiki/Probability_density_function) of the [normal distribution](https://en.wikipedia.org/wiki/Normal_distribution)
 * [sinc function](https://en.wikipedia.org/wiki/Sinc_function)
 * [delta function](https://en.wikipedia.org/wiki/Dirac_delta_function)
-* [decibel function](https://en.wikipedia.org/wiki/Decibel)
+
+### [decibel.hh](decibel.hh)
+
+[Decibel](https://en.wikipedia.org/wiki/Decibel) calculation helpers.
 
 ### [resampler.hh](resampler.hh)
 
diff --git a/decibel.hh b/decibel.hh
new file mode 100644
index 0000000..256f041
--- /dev/null
+++ b/decibel.hh
@@ -0,0 +1,44 @@
+/*
+Decibel calculation helpers
+
+Copyright 2018 Ahmet Inan <inan@aicodix.de>
+*/
+
+#pragma once
+
+namespace DSP {
+
+template <typename TYPE>
+TYPE decibel(TYPE v)
+{
+#if 0
+	return TYPE(10) * log10(v);
+#else
+	static constexpr TYPE
+		// 2*1024*10/l(10)
+		scale = 8894.350989378597430295120259412072085389250678859091274024013479236L,
+		inv1 = TYPE(1) / TYPE(1),
+		inv3 = TYPE(1) / TYPE(3),
+		inv5 = TYPE(1) / TYPE(5),
+		inv7 = TYPE(1) / TYPE(7),
+		inv9 = TYPE(1) / TYPE(9),
+		inv11 = TYPE(1) / TYPE(11),
+		inv13 = TYPE(1) / TYPE(13);
+	TYPE x = v;
+	for (int i = 0; i < 10; ++i)
+		x = sqrt(x);
+	x = (x - TYPE(1)) / (x + TYPE(1));
+	TYPE xx = x * x;
+	return scale * x * (xx * (xx * (xx * (xx * (xx * (xx *
+		inv13 + inv11) + inv9) + inv7) + inv5) + inv3) + inv1);
+#endif
+}
+
+template <typename TYPE>
+TYPE idecibel(TYPE dB)
+{
+	return pow(TYPE(10), dB / TYPE(10));
+}
+
+}
+
diff --git a/utils.hh b/utils.hh
index f5165bb..8a004e5 100644
--- a/utils.hh
+++ b/utils.hh
@@ -40,31 +40,5 @@ TYPE delta(TYPE x)
 	return TYPE(0) == x ? TYPE(1) : TYPE(0);
 }
 
-template <typename TYPE>
-TYPE decibel(TYPE v)
-{
-#if 0
-	return TYPE(10) * log10(v);
-#else
-	static constexpr TYPE
-		// 2*1024*10/l(10)
-		scale = 8894.350989378597430295120259412072085389250678859091274024013479236L,
-		inv1 = TYPE(1) / TYPE(1),
-		inv3 = TYPE(1) / TYPE(3),
-		inv5 = TYPE(1) / TYPE(5),
-		inv7 = TYPE(1) / TYPE(7),
-		inv9 = TYPE(1) / TYPE(9),
-		inv11 = TYPE(1) / TYPE(11),
-		inv13 = TYPE(1) / TYPE(13);
-	TYPE x = v;
-	for (int i = 0; i < 10; ++i)
-		x = sqrt(x);
-	x = (x - TYPE(1)) / (x + TYPE(1));
-	TYPE xx = x * x;
-	return scale * x * (xx * (xx * (xx * (xx * (xx * (xx *
-		inv13 + inv11) + inv9) + inv7) + inv5) + inv3) + inv1);
-#endif
-}
-
 }