diff --git a/sdrbase/util/db.cpp b/sdrbase/util/db.cpp
index eada6a8c3..8dadedd1d 100644
--- a/sdrbase/util/db.cpp
+++ b/sdrbase/util/db.cpp
@@ -17,7 +17,7 @@
 #include "util/db.h"
 #include <cmath>
 
-Real CalcDb::dbPower(Real magsq)
+Real CalcDb::dbPower(Real magsq, Real floordB)
 {
 	if (magsq > 0)
 	{
@@ -25,6 +25,6 @@ Real CalcDb::dbPower(Real magsq)
 	}
 	else
 	{
-		return 0;
+		return floordB;
 	}
 }
diff --git a/sdrbase/util/db.h b/sdrbase/util/db.h
index 3446c678c..f5c746a24 100644
--- a/sdrbase/util/db.h
+++ b/sdrbase/util/db.h
@@ -22,7 +22,7 @@
 class CalcDb
 {
 public:
-	static Real dbPower(Real magsq);
+	static Real dbPower(Real magsq, Real floordB = -100.0f);
 };
 
 #endif /* INCLUDE_UTIL_DB_H_ */