diff --git a/mlair/model_modules/convolutional_networks.py b/mlair/model_modules/convolutional_networks.py
index 2d8fd9e2fe4292ef7989d932d9b7d4fc9fbe756d..329d19520d27898a9818b951bb7a4f35ef2c97a8 100644
--- a/mlair/model_modules/convolutional_networks.py
+++ b/mlair/model_modules/convolutional_networks.py
@@ -83,16 +83,16 @@ class CNN(AbstractModelClass):
         """
         x_input = keras.layers.Input(shape=self._input_shape)
         kernel = (self.kernel_size, 1)
-        x_in = keras.layers.Conv2D(filters=16, kernel_size=kernel,
+        x_in = keras.layers.Conv2D(filters=16, kernel_size=(73, 1),
                                    kernel_initializer=self.kernel_initializer,
                                    kernel_regularizer=self.kernel_regularizer)(x_input)
         x_in = self.activation()(x_in)
-        x_in = keras.layers.Conv2D(filters=32, kernel_size=kernel,
+        x_in = keras.layers.Conv2D(filters=32, kernel_size=(49, 1),
                                    kernel_initializer=self.kernel_initializer,
                                    kernel_regularizer=self.kernel_regularizer)(x_in)
         x_in = self.activation()(x_in)
-        x_in = keras.layers.MaxPooling2D(kernel, strides=(1, 1), padding='valid')(x_in)
-        x_in = keras.layers.Conv2D(filters=64, kernel_size=kernel,
+        x_in = keras.layers.MaxPooling2D((25, 1), strides=(1, 1), padding='valid')(x_in)
+        x_in = keras.layers.Conv2D(filters=64, kernel_size=(13, 1),
                                    kernel_initializer=self.kernel_initializer,
                                    kernel_regularizer=self.kernel_regularizer)(x_in)
         x_in = self.activation()(x_in)