diff --git a/lasp/lasp_measurement.py b/lasp/lasp_measurement.py
index be65350..2bb1ee4 100644
--- a/lasp/lasp_measurement.py
+++ b/lasp/lasp_measurement.py
@@ -16,17 +16,17 @@ is assumed to be acoustic data.
 'sensitivity': (Optionally) the stored sensitivity of the record channels.
                This can be a single value, or a list of sensitivities for
                each channel. Both representations are allowed.
-'qtys' : (Optionally): list of quantities that is recorded for each channel', if
-this array is not found. Quantities are defaulted to 'Number / Full scale'
+'qtys' : (Optionally): list of quantities that is recorded for each channel',
+if this array is not found. Quantities are defaulted to 'Number / Full scale'
 
 - Datasets:
 
 'audio': 3-dimensional array of blocks of audio data. The first axis is the
-block index, the second axis the sample number and the third axis is the channel
-number. The data type is either int16, int32 or float64 / float32. If raw data
-is stored as integer values (int16, int32), the actual values should be
-pre-scaled by its maximum positive number (2**(nb-1) - 1), such that the
-corresponding 'number' lies between -1.0 and 1.0. 
+block index, the second axis the sample number and the third axis is the
+channel number. The data type is either int16, int32 or float64 / float32. If
+raw data is stored as integer values (int16, int32), the actual values should
+be pre-scaled by its maximum positive number (2**(nb-1) - 1), such that the
+corresponding 'number' lies between -1.0 and 1.0.
 
 'video': 4-dimensional array of video frames. The first index is the frame
          number, the second the x-value of the pixel and the third is the
@@ -68,6 +68,7 @@ def getSampWidth(dtype):
     else:
         raise ValueError('Invalid data type: %s' % dtype)
 
+
 def scaleBlockSens(block, sens):
     """Scale a block of raw data to return raw acoustic pressure data.
 
@@ -155,8 +156,8 @@ class IterRawData:
             stop_offset = self.blocksize
         # print(f'block: {block}, starto: {start_offset}, stopo {stop_offset}')
 
-        self.i +=1
-        return self.fa[block,start_offset:stop_offset,:][:,self.channels]
+        self.i += 1
+        return self.fa[block, start_offset:stop_offset, :][:, self.channels]
 
 
 class IterData(IterRawData):
diff --git a/lasp/lasp_octavefilter.py b/lasp/lasp_octavefilter.py
index 5f29fde..b2f3a6b 100644
--- a/lasp/lasp_octavefilter.py
+++ b/lasp/lasp_octavefilter.py
@@ -315,5 +315,3 @@ class SosOctaveFilterBank(SosFilterBank):
         """
         self.designer = OctaveBankDesigner(fs)
         SosFilterBank.__init__(self, fs, xmin, xmax)
-
-
diff --git a/lasp/tools/tools.py b/lasp/tools/tools.py
index 41b9d91..752ed7b 100644
--- a/lasp/tools/tools.py
+++ b/lasp/tools/tools.py
@@ -114,8 +114,8 @@ def smoothSpectralData(freq, M, sw: SmoothingWidth,
         raise Warning('Check if \'Noct\' is entered correctly')
     assert len(freq) == len(M), 'f and M should have equal length'
 
-    if st == SmoothingType.ps:
-        assert np.min(M) >= 0, 'absolute magnitude M cannot be negative'
+#    if st == SmoothingType.ps:
+#        assert np.min(M) >= 0, 'absolute magnitude M cannot be negative'
     if st == SmoothingType.levels and isinstance(M.dtype, complex):
         raise RuntimeError('Decibel input should be real-valued')
 
@@ -167,7 +167,7 @@ def smoothSpectralData(freq, M, sw: SmoothingWidth,
         # Calculate window
         g = np.zeros(xu-xl)
         for n, xi in enumerate(range(xl, xu)):
-            fi = f[xi]  # current frequency
+            fi = freq[xi]  # current frequency
             g[n] = np.sqrt( 1/ ((1+((fi/fc - fc/fi)*(1.507*Noct))**6)) )
         g /= np.sum(g)  # normalize: integral=1