diff --git a/lisainstrument/hexagon.py b/lisainstrument/hexagon.py
index 22752179c2030b1d98bc797f7bdf51a9bc7c7333..17d0541bece6f14b7e663fa9970b7283245f0051 100644
--- a/lisainstrument/hexagon.py
+++ b/lisainstrument/hexagon.py
@@ -45,7 +45,8 @@ class Hexagon():
                  primary_laser_asd=100,
                  locked_laser_asd=60,
                  offset_freqs='default',
-                 central_freq=2.816E14):
+                 central_freq=2.816E14,
+                 laser_shape='white+infrared'):
 
         self.simulated = False
 
@@ -60,6 +61,7 @@ class Hexagon():
 
         self.primary_laser_asd = float(primary_laser_asd)
         self.locked_laser_asd = float(locked_laser_asd)
+        self.laser_shape = laser_shape
 
         self.central_freq = float(central_freq)
         if offset_freqs == 'default':
@@ -90,7 +92,7 @@ class Hexagon():
         logger.debug("Generating laser noise")
         self.laser_noises = np.empty((self.size, 3)) # (size, laser) [Hz]
         # Laser 1 has its own stability
-        self.laser_noises[:, 0] = noises.laser(self.fs, self.size, self.primary_laser_asd)
+        self.laser_noises[:, 0] = noises.laser(self.fs, self.size, self.primary_laser_asd, self.laser_shape)
         # Laser 2 replicated laser 1 with added locking noise
         self.laser_noises[:, 1] = self.laser_noises[:, 0] \
             + noises.white(self.fs, self.size, self.locked_laser_asd)