diff --git a/pycbc/conversions.py b/pycbc/conversions.py
index 832ce926667..83799976fa2 100644
--- a/pycbc/conversions.py
+++ b/pycbc/conversions.py
@@ -662,7 +662,8 @@ def distance_from_chirp_distance_mchirp(chirp_distance, mchirp, ref_mass=1.4):
     return chirp_distance * (2.**(-1./5) * ref_mass / mchirp)**(-5./6)
 
 
-def _det_tc(detector_name, ra, dec, tc, ref_frame='geocentric'):
+_detector_cache = {}
+def det_tc(detector_name, ra, dec, tc, ref_frame='geocentric'):
     """Returns the coalescence time of a signal in the given detector.
 
     Parameters
@@ -686,26 +687,24 @@ def _det_tc(detector_name, ra, dec, tc, ref_frame='geocentric'):
     """
     if ref_frame == detector_name:
         return tc
-    detector = Detector(detector_name)
+    if detector_name not in _detector_cache:
+        _detector_cache[detector_name] = Detector(detector_name)
+    detector = _detector_cache[detector_name]
     if ref_frame == 'geocentric':
         return tc + detector.time_delay_from_earth_center(ra, dec, tc)
     else:
         other = Detector(ref_frame)
         return tc + detector.time_delay_from_detector(other, ra, dec, tc)
 
-det_tc = numpy.vectorize(_det_tc)
-
-def _optimal_orientation_from_detector(detector_name, tc):
+def optimal_orientation_from_detector(detector_name, tc):
     """ Low-level function to be called from _optimal_dec_from_detector
     and _optimal_ra_from_detector"""
 
     d = Detector(detector_name)
     ra, dec = d.optimal_orientation(tc)
-
     return ra, dec
 
-
-def _optimal_dec_from_detector(detector_name, tc):
+def optimal_dec_from_detector(detector_name, tc):
     """For a given detector and GPS time, return the optimal orientation
     (directly overhead of the detector) in declination.
 
@@ -722,13 +721,9 @@ def _optimal_dec_from_detector(detector_name, tc):
     float :
         The declination of the signal, in radians.
     """
-    return _optimal_orientation_from_detector(detector_name, tc)[1]
-
-
-optimal_dec_from_detector = numpy.vectorize(_optimal_dec_from_detector)
+    return optimal_orientation_from_detector(detector_name, tc)[1]
 
-
-def _optimal_ra_from_detector(detector_name, tc):
+def optimal_ra_from_detector(detector_name, tc):
     """For a given detector and GPS time, return the optimal orientation
     (directly overhead of the detector) in right ascension.
 
@@ -745,11 +740,7 @@ def _optimal_ra_from_detector(detector_name, tc):
     float :
         The declination of the signal, in radians.
     """
-    return _optimal_orientation_from_detector(detector_name, tc)[0]
-
-
-optimal_ra_from_detector = numpy.vectorize(_optimal_ra_from_detector)
-
+    return optimal_orientation_from_detector(detector_name, tc)[0]
 
 #
 # =============================================================================
diff --git a/pycbc/distributions/angular.py b/pycbc/distributions/angular.py
index b321368dec4..ae85be60143 100644
--- a/pycbc/distributions/angular.py
+++ b/pycbc/distributions/angular.py
@@ -89,6 +89,7 @@ def __init__(self, cyclic_domain=False, **params):
                     "got [{a},{b})".format(x=self._domain.min,
                     y=self._domain.max, a=bnds.min,
                     b=bnds.max))
+
             # update
             params[p] = bnds
         super(UniformAngle, self).__init__(**params)