diff --git a/sbi/inference/posteriors/ensemble_posterior.py b/sbi/inference/posteriors/ensemble_posterior.py
index 295f2085e..342028056 100644
--- a/sbi/inference/posteriors/ensemble_posterior.py
+++ b/sbi/inference/posteriors/ensemble_posterior.py
@@ -242,7 +242,9 @@ def set_default_x(self, x: Tensor) -> "NeuralPosterior":
             `EnsemblePosterior` that will use a default `x` when not explicitly
             passed.
         """
-        self._x = x.to(self._device)
+        self._x =  process_x(
+            x, x_shape=None, allow_iid_x=self.potential_fn.allow_iid_x
+        ).to(self._device)
 
         for posterior in self.posteriors:
             posterior.set_default_x(x)