diff --git a/tests/test_encoder.py b/tests/test_encoder.py
index 711ad195..46266f29 100644
--- a/tests/test_encoder.py
+++ b/tests/test_encoder.py
@@ -4,7 +4,7 @@ import unittest
 import torch as T
 from tests import get_tests_input_path
 
-from mozilla_voice_tts.speaker_encoder.loss import GE2ELoss
+from mozilla_voice_tts.speaker_encoder.losses import GE2ELoss, AngleProtoLoss
 from mozilla_voice_tts.speaker_encoder.model import SpeakerEncoder
 from mozilla_voice_tts.utils.io import load_config
 
@@ -59,6 +59,7 @@ class GE2ELossTests(unittest.TestCase):
         dummy_input = T.ones(4, 5, 64)  # num_speaker x num_utterance x dim
         loss = GE2ELoss(loss_method="softmax")
         output = loss.forward(dummy_input)
+        assert output.item() >= 0.0
         # check speaker loss with orthogonal d-vectors
         dummy_input = T.empty(3, 64)
         dummy_input = T.nn.init.orthogonal(dummy_input)
@@ -73,6 +74,34 @@ class GE2ELossTests(unittest.TestCase):
         output = loss.forward(dummy_input)
         assert output.item() < 0.005
 
+class AngleProtoLossTests(unittest.TestCase):
+    # pylint: disable=R0201
+    def test_in_out(self):
+        # check random input
+        dummy_input = T.rand(4, 5, 64)  # num_speaker x num_utterance x dim
+        loss = AngleProtoLoss()
+        output = loss.forward(dummy_input)
+        assert output.item() >= 0.0
+
+        # check all zeros
+        dummy_input = T.ones(4, 5, 64)  # num_speaker x num_utterance x dim
+        loss = AngleProtoLoss()
+        output = loss.forward(dummy_input)
+        assert output.item() >= 0.0
+
+        # check speaker loss with orthogonal d-vectors
+        dummy_input = T.empty(3, 64)
+        dummy_input = T.nn.init.orthogonal(dummy_input)
+        dummy_input = T.cat(
+            [
+                dummy_input[0].repeat(5, 1, 1).transpose(0, 1),
+                dummy_input[1].repeat(5, 1, 1).transpose(0, 1),
+                dummy_input[2].repeat(5, 1, 1).transpose(0, 1),
+            ]
+        )  # num_speaker x num_utterance x dim
+        loss = AngleProtoLoss()
+        output = loss.forward(dummy_input)
+        assert output.item() < 0.005
 
 # class LoaderTest(unittest.TestCase):
 #     def test_output(self):