diff --git a/lib/src/enharmonic.dart b/lib/src/enharmonic.dart
index 5f2eb38f..467cf7b5 100644
--- a/lib/src/enharmonic.dart
+++ b/lib/src/enharmonic.dart
@@ -9,11 +9,7 @@ abstract class Enharmonic<T extends MusicItem>
   final int semitones;
 
   /// Creates a new [Enharmonic].
-  const Enharmonic(this.semitones)
-      : assert(
-          semitones > 0 && semitones <= chromaticDivisions,
-          'Semitones must be in chromatic divisions range',
-        );
+  const Enharmonic(this.semitones);
 
   /// Returns the items sharing the same [semitones].
   Set<T> get items;
diff --git a/lib/src/note/enharmonic_note.dart b/lib/src/note/enharmonic_note.dart
index 52886cd7..50c0acb1 100644
--- a/lib/src/note/enharmonic_note.dart
+++ b/lib/src/note/enharmonic_note.dart
@@ -1,7 +1,11 @@
 part of '../../music_notes.dart';
 
 class EnharmonicNote extends Enharmonic<Note> {
-  const EnharmonicNote(super.semitones);
+  const EnharmonicNote(super.semitones)
+      : assert(
+          semitones > 0 && semitones <= chromaticDivisions,
+          'Semitones must be in chromatic divisions range',
+        );
 
   static const c = EnharmonicNote(1);
   static const cSharp = EnharmonicNote(2);
diff --git a/test/src/interval/enharmonic_interval_test.dart b/test/src/interval/enharmonic_interval_test.dart
index a9c1ecde..6fa2d9b8 100644
--- a/test/src/interval/enharmonic_interval_test.dart
+++ b/test/src/interval/enharmonic_interval_test.dart
@@ -66,6 +66,11 @@ void main() {
             const Interval.imperfect(7, ImperfectQuality.major),
             const Interval.perfect(8, PerfectQuality.diminished),
           });
+          expect(const EnharmonicInterval(13).items, {
+            const Interval.imperfect(7, ImperfectQuality.augmented),
+            const Interval.perfect(8, PerfectQuality.perfect),
+            const Interval.imperfect(9, ImperfectQuality.diminished),
+          });
         },
       );
     });
diff --git a/test/src/note/enharmonic_note_test.dart b/test/src/note/enharmonic_note_test.dart
index 9dc21566..d74acf84 100644
--- a/test/src/note/enharmonic_note_test.dart
+++ b/test/src/note/enharmonic_note_test.dart
@@ -5,6 +5,16 @@ import 'package:test/test.dart';
 
 void main() {
   group('EnharmonicNote', () {
+    group('constructor', () {
+      test(
+        'should throw an assertion error when arguments are incorrect',
+        () {
+          expect(() => EnharmonicNote(-2), throwsA(isA<AssertionError>()));
+          expect(() => EnharmonicNote(13), throwsA(isA<AssertionError>()));
+        },
+      );
+    });
+
     group('.items', () {
       test('should return the correct Notes for this EnharmonicNote', () {
         expect(EnharmonicNote.c.items, {