diff --git a/src/lgdo/types/array.py b/src/lgdo/types/array.py
index 2dc3627b..cdf1436d 100644
--- a/src/lgdo/types/array.py
+++ b/src/lgdo/types/array.py
@@ -6,7 +6,7 @@
 from __future__ import annotations
 
 import logging
-from collections.abc import Iterator
+from collections.abc import Collection, Iterator
 from typing import Any
 
 import awkward as ak
@@ -126,19 +126,27 @@ def trim_capacity(self) -> None:
         "Set capacity to be minimum needed to support Array size"
         self.reserve_capacity(np.prod(self.shape))
 
-    def resize(self, new_size: int, trim=False) -> None:
+    def resize(self, new_size: int | Collection[int], trim=False) -> None:
         """Set size of Array in rows. Only change capacity if it must be
         increased to accommodate new rows; in this case double capacity.
-        If trim is True, capacity will be set to match size."""
+        If trim is True, capacity will be set to match size. If new_size
+        is an int, do not change size of inner dimensions.
 
-        self._size = new_size
+        If new_size is a collection, internal memory will be re-allocated, so
+        this should be done only rarely!"""
 
-        if trim and new_size != self.get_capacity:
-            self.reserve_capacity(new_size)
+        if isinstance(new_size, Collection):
+            self._size = new_size[0]
+            self._nda.resize(new_size)
+        else:
+            self._size = new_size
+
+            if trim and new_size != self.get_capacity:
+                self.reserve_capacity(new_size)
 
-        # If capacity is not big enough, set to next power of 2 big enough
-        if new_size > self.get_capacity():
-            self.reserve_capacity(int(2 ** (np.ceil(np.log2(new_size)))))
+            # If capacity is not big enough, set to next power of 2 big enough
+            if new_size > self.get_capacity():
+                self.reserve_capacity(int(2 ** (np.ceil(np.log2(new_size)))))
 
     def append(self, value: np.ndarray) -> None:
         "Append value to end of array (with copy)"
diff --git a/src/lgdo/types/waveformtable.py b/src/lgdo/types/waveformtable.py
index 4fffeeb4..ffc3b5ca 100644
--- a/src/lgdo/types/waveformtable.py
+++ b/src/lgdo/types/waveformtable.py
@@ -112,12 +112,10 @@ def __init__(
         if not isinstance(t0, Array):
             shape = (size,)
             t0_dtype = t0.dtype if hasattr(t0, "dtype") else np.float32
-            nda = (
-                t0 if isinstance(t0, np.ndarray) else np.full(shape, t0, dtype=t0_dtype)
-            )
-            if nda.shape != shape:
-                nda.resize(shape, refcheck=True)
-            t0 = Array(nda=nda)
+            if isinstance(t0, np.ndarray):
+                t0 = Array(nda=t0, shape=shape, dtype=t0_dtype)
+            else:
+                t0 = Array(fill_val=t0, shape=shape, dtype=t0_dtype)
 
         if t0_units is not None:
             t0.attrs["units"] = f"{t0_units}"
@@ -125,12 +123,11 @@ def __init__(
         if not isinstance(dt, Array):
             shape = (size,)
             dt_dtype = dt.dtype if hasattr(dt, "dtype") else np.float32
-            nda = (
-                dt if isinstance(dt, np.ndarray) else np.full(shape, dt, dtype=dt_dtype)
-            )
-            if nda.shape != shape:
-                nda.resize(shape, refcheck=True)
-            dt = Array(nda=nda)
+            if isinstance(dt, np.ndarray):
+                dt = Array(nda=dt, shape=shape, dtype=dt_dtype)
+            else:
+                dt = Array(fill_val=dt, shape=shape, dtype=dt_dtype)
+
         if dt_units is not None:
             dt.attrs["units"] = f"{dt_units}"
 
@@ -174,14 +171,15 @@ def __init__(
                         if hasattr(values, "dtype")
                         else np.dtype(np.float64)
                     )
-                nda = (
-                    values
-                    if isinstance(values, np.ndarray)
-                    else np.zeros(shape, dtype=dtype)
-                )
-                if nda.shape != shape:
-                    nda.resize(shape, refcheck=True)
-                values = ArrayOfEqualSizedArrays(dims=(1, 1), nda=nda)
+                if isinstance(values, np.ndarray):
+                    values = ArrayOfEqualSizedArrays(
+                        dims=(1, 1), nda=values, shape=shape, dtype=dtype
+                    )
+                else:
+                    values = ArrayOfEqualSizedArrays(
+                        dims=(1, 1), fill_val=0, shape=shape, dtype=dtype
+                    )
+
         if values_units is not None:
             values.attrs["units"] = f"{values_units}"
 
@@ -215,7 +213,7 @@ def wf_len(self, wf_len) -> None:
             return
         shape = self.values.nda.shape
         shape = (shape[0], wf_len)
-        self.values.nda.resize(shape, refcheck=True)
+        self.values.resize(shape)
 
     def resize_wf_len(self, new_len: int) -> None:
         """Alias for `wf_len.setter`, for when we want to make it clear in
diff --git a/tests/types/test_waveformtable.py b/tests/types/test_waveformtable.py
index f81e40ce..a9df1566 100644
--- a/tests/types/test_waveformtable.py
+++ b/tests/types/test_waveformtable.py
@@ -25,6 +25,15 @@ def test_init():
     assert (wft.values.nda == np.zeros(shape=(10, 1000))).all()
     assert wft.values.nda.dtype == np.float64
 
+    wft = WaveformTable(
+        size=10, dt=np.zeros(5), t0=np.zeros(5), values=np.zeros((5, 50))
+    )
+    assert (wft.t0.nda == np.zeros(10)).all()
+    assert (wft.dt.nda == np.zeros(10)).all()
+    assert isinstance(wft.values, lgdo.ArrayOfEqualSizedArrays)
+    assert (wft.values.nda == np.zeros(shape=(10, 50))).all()
+    assert wft.values.nda.dtype == np.float64
+
     wft = WaveformTable(
         values=lgdo.ArrayOfEqualSizedArrays(shape=(10, 1000), fill_val=69)
     )
@@ -85,3 +94,7 @@ def test_init():
 
     wft = WaveformTable(t0=[1, 1, 1], dt=[2, 2, 2], wf_len=1000, dtype=np.float32)
     assert wft.values.nda.dtype == np.float32
+
+    wft = WaveformTable(10, wf_len=20)
+    wft.wf_len = 30
+    assert wft.wf_len == 30