diff --git a/src/scgenerator/spectra.py b/src/scgenerator/spectra.py
index f044761..a5bd938 100644
--- a/src/scgenerator/spectra.py
+++ b/src/scgenerator/spectra.py
@@ -56,6 +56,7 @@ class Spectrum(np.ndarray):
         obj.ifft = ifft
         obj.l = 2 * np.pi * units.c / obj.w
         obj.l_order = np.argsort(obj.l)
+        obj.spectrum_factor = (obj.t[1] - obj.t[0]) / np.sqrt(2 * np.pi)
 
         if not (len(obj.w) == len(obj.t) == len(obj.l) == obj.shape[-1]):
             raise ValueError(
@@ -75,6 +76,7 @@ class Spectrum(np.ndarray):
         self.l = getattr(obj, "l", None)
         self.w_order = getattr(obj, "w_order", None)
         self.l_order = getattr(obj, "l_order", None)
+        self.spectrum_factor = getattr(obj, "spectrum_factor", None)
         self.ifft = getattr(obj, "ifft", None)
 
     def __getitem__(self, key) -> "Spectrum":
@@ -90,15 +92,11 @@ class Spectrum(np.ndarray):
 
     @property
     def wl_int(self):
-        return units.to_WL(math.abs2(self), self.l)[..., self.l_order]
-
-    @property
-    def freq_int(self):
-        return math.abs2(self.freq_amp)
+        return units.to_WL(math.abs2(self * self.spectrum_factor), self.l)[..., self.l_order]
 
     @property
     def afreq_int(self):
-        return math.abs2(self.freq_amp)
+        return math.abs2(self.afreq_amp)
 
     @property
     def time_int(self):
@@ -117,13 +115,9 @@ class Spectrum(np.ndarray):
             / np.abs(self)
         )[..., self.l_order]
 
-    @property
-    def freq_amp(self):
-        return self[..., self.w_order[::-1]]
-
     @property
     def afreq_amp(self):
-        return self[..., self.w_order[::-1]]
+        return self[..., self.w_order[::-1]] * self.spectrum_factor
 
     @property
     def time_amp(self):
@@ -132,7 +126,7 @@ class Spectrum(np.ndarray):
     @property
     def wl_max(self):
         if self.ndim == 1:
-            return self.l[np.argmax(self.wl_int, axis=-1)]
+            return self.wl_disp[np.argmax(self.wl_int, axis=-1)]
         return np.array([s.wl_max for s in self])
 
     @property
@@ -149,6 +143,9 @@ class Spectrum(np.ndarray):
     def measure(self) -> tuple[float, float, float]:
         return pulse.measure_field(self.t, self.time_amp)
 
+    freq_int = afreq_int
+    freq_amp = afreq_amp
+
 
 class Propagation(Generic[ParamsOrNone]):
     io: PropagationIOHandler