diff --git a/specparam/objs/data.py b/specparam/objs/data.py
index 4006d1ab..7823542f 100644
--- a/specparam/objs/data.py
+++ b/specparam/objs/data.py
@@ -379,3 +379,64 @@ def add_data(self, freqs, spectrogram, freq_range=None):
         if np.any(self.freqs):
             self._reset_time_results()
         super().add_data(freqs, spectrogram, freq_range)
+
+
+class BaseData3D(BaseData2DT):
+    """Base object for managing data for spectral parameterization - for 3D data."""
+
+    def __init__(self):
+
+        BaseData2DT.__init__(self)
+
+        self.spectrograms = None
+
+
+    @property
+    def has_data(self):
+        """Redefine has_data marker to reflect the spectrograms attribute."""
+
+        return bool(np.any(self.spectrograms))
+
+
+    @property
+    def n_time_windows(self):
+        """How many time windows are included in the model object."""
+
+        return self.spectrograms[0].shape[1] if self.has_data else 0
+
+
+    @property
+    def n_events(self):
+        """How many events are included in the model object."""
+
+        return len(self.spectrograms)
+
+
+    def add_data(self, freqs, spectrograms, freq_range=None):
+        """Add data (frequencies and spectrograms) to the current object.
+
+        Parameters
+        ----------
+        freqs : 1d array
+            Frequency values for the power spectra, in linear space.
+        spectrograms : 3d array or list of 2d array
+            Matrix of power values, in linear space.
+            If a list of 2d arrays, each should be have the same shape of [n_freqs, n_time_windows].
+            If a 3d array, should have shape [n_events, n_freqs, n_time_windows].
+        freq_range : list of [float, float], optional
+            Frequency range to restrict power spectra to. If not provided, keeps the entire range.
+        """
+
+        # If given a list of spectrograms, convert to 3d array
+        if isinstance(spectrograms, list):
+            spectrograms = np.array(spectrograms)
+
+        # If is a 3d array, add to object as spectrograms
+        if spectrograms.ndim == 3:
+
+            self.freqs, self.spectrograms, self.freq_range, self.freq_res = \
+                self._prepare_data(freqs, spectrograms, freq_range, 3)
+
+        # Otherwise, pass through 2d array to underlying object method
+        else:
+            super().add_data(freqs, spectrograms, freq_range)
diff --git a/specparam/tests/objs/test_data.py b/specparam/tests/objs/test_data.py
index 58adc205..63e887f6 100644
--- a/specparam/tests/objs/test_data.py
+++ b/specparam/tests/objs/test_data.py
@@ -93,3 +93,23 @@ def test_base_data2dt_add_data():
     assert tdata2dt.has_data
     assert np.all(tdata2dt.spectrogram)
     assert tdata2dt.n_time_windows
+
+## 3D Data Object
+
+def test_base_data3d():
+
+    tdata3d = BaseData3D()
+    assert tdata3d
+    assert isinstance(tdata3d, BaseData)
+    assert isinstance(tdata3d, BaseData2D)
+    assert isinstance(tdata3d, BaseData2DT)
+    assert isinstance(tdata3d, BaseData3D)
+
+def test_base_data3d_add_data():
+
+    tdata3d = BaseData3D()
+    freqs, pows = np.array([1, 2, 3]), np.array([[10, 10, 10], [20, 20, 20]]).T
+    tdata3d.add_data(freqs, np.array([pows, pows]))
+    assert tdata3d.has_data
+    assert np.all(tdata3d.spectrograms)
+    assert tdata3d.n_events