diff --git a/deployment/exporters/acoustic_exporter.py b/deployment/exporters/acoustic_exporter.py
index 849dae5d..2adefe9a 100644
--- a/deployment/exporters/acoustic_exporter.py
+++ b/deployment/exporters/acoustic_exporter.py
@@ -4,6 +4,7 @@
 
 import onnx
 import onnxsim
+import onnxslim
 import torch
 import yaml
 
@@ -344,9 +345,11 @@ def _perform_spk_mix(self, spk_mix: Dict[str, float]):
         return spk_mix_embed
 
     def _optimize_fs2_aux_graph(self, fs2: onnx.ModelProto) -> onnx.ModelProto:
-        print(f'Running ONNX Simplifier on {self.fs2_aux_class_name}...')
-        fs2, check = onnxsim.simplify(fs2, include_subgraph=True)
-        assert check, 'Simplified ONNX model could not be validated'
+        # print(f'Running ONNX Simplifier on {self.fs2_aux_class_name}...')
+        # fs2, check = onnxsim.simplify(fs2, include_subgraph=True)
+        # assert check, 'Simplified ONNX model could not be validated'
+        print(f'Running OnnxSlim on {self.fs2_aux_class_name}...')
+        fs2 = onnxslim.slim(fs2)
         onnx_helper.model_reorder_io_list(
             fs2, 'input',
             target_name='languages', insert_after_name='tokens'
diff --git a/deployment/exporters/variance_exporter.py b/deployment/exporters/variance_exporter.py
index 82808ec0..d0003dea 100644
--- a/deployment/exporters/variance_exporter.py
+++ b/deployment/exporters/variance_exporter.py
@@ -4,6 +4,7 @@
 
 import onnx
 import onnxsim
+import onnxslim
 import torch
 import yaml
 
@@ -82,6 +83,8 @@ def __init__(
             if self.freeze_spk is not None:
                 self.model.register_buffer('frozen_spk_embed', self._perform_spk_mix(self.freeze_spk[1]))
 
+        self.use_melody_encoder = hparams['use_melody_encoder']
+
     def build_model(self) -> DiffSingerVarianceONNX:
         model = DiffSingerVarianceONNX(
             vocab_size=len(self.phoneme_dictionary),
@@ -649,9 +652,11 @@ def _optimize_linguistic_graph(self, linguistic: onnx.ModelProto) -> onnx.ModelP
                 'encoder_out': (1, 'n_tokens', hparams['hidden_size'])
             }
         )
-        print(f'Running ONNX Simplifier on {self.fs2_class_name}...')
-        linguistic, check = onnxsim.simplify(linguistic, include_subgraph=True)
-        assert check, 'Simplified ONNX model could not be validated'
+        # print(f'Running ONNX Simplifier on {self.fs2_class_name}...')
+        # linguistic, check = onnxsim.simplify(linguistic, include_subgraph=True)
+        # assert check, 'Simplified ONNX model could not be validated'
+        print(f'Running OnnxSlim on {self.fs2_class_name}...')
+        linguistic = onnxslim.slim(linguistic)
         onnx_helper.model_reorder_io_list(
             linguistic, 'input',
             target_name='languages', insert_after_name='tokens'
@@ -678,8 +683,11 @@ def _optimize_merge_pitch_predictor_graph(
         onnx_helper.model_override_io_shapes(
             pitch_pre, output_shapes={'pitch_cond': (1, 'n_frames', hparams['hidden_size'])}
         )
-        pitch_pre, check = onnxsim.simplify(pitch_pre, include_subgraph=True)
-        assert check, 'Simplified ONNX model could not be validated'
+        if self.use_melody_encoder:
+            pitch_pre = onnxslim.slim(pitch_pre)
+        else:
+            pitch_pre, check = onnxsim.simplify(pitch_pre, include_subgraph=True)
+            assert check, 'Simplified ONNX model could not be validated'
 
         onnx_helper.model_override_io_shapes(
             pitch_predictor, output_shapes={'pitch_pred': (1, 'n_frames')}
diff --git a/requirements-onnx.txt b/requirements-onnx.txt
index dda53148..4eea23b0 100644
--- a/requirements-onnx.txt
+++ b/requirements-onnx.txt
@@ -12,6 +12,7 @@ MonkeyType==23.3.0
 numpy<2.0.0
 onnx~=1.16.0
 onnxsim~=0.4.36
+onnxslim
 praat-parselmouth==0.4.3
 pyworld==0.3.4
 PyYAML
diff --git a/requirements.txt b/requirements.txt
index 8f79e238..6a96ee6d 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -12,6 +12,7 @@ MonkeyType==23.3.0
 numpy<2.0.0
 onnx~=1.16.0
 onnxsim~=0.4.36
+onnxslim
 praat-parselmouth==0.4.3
 pyworld==0.3.4
 PyYAML