diff --git a/lib/fil6521.f90 b/lib/fil6521.f90
index 6e78e63ab..ef4b5435f 100644
--- a/lib/fil6521.f90
+++ b/lib/fil6521.f90
@@ -19,14 +19,15 @@ subroutine fil6521(c1,n1,c2,n2)
   complex c2(n1/NDOWN)
 
 ! Filter coefficients:
-  real a(-NH:NH)
+  real a(-NH:NH+NTAPS/3)
   data a/                                                                &
        -0.011958606980,-0.013888627387,-0.015601306443,-0.010602249570,  &
         0.003804023436, 0.028320058273, 0.060903935217, 0.096841904411,  &
         0.129639871228, 0.152644580853, 0.160917511283, 0.152644580853,  &
         0.129639871228, 0.096841904411, 0.060903935217, 0.028320058273,  &
         0.003804023436,-0.010602249570,-0.015601306443,-0.013888627387,  &
-       -0.011958606980/
+        -0.011958606980,1.43370769e-019,2.64031087e-006,6.25548654e+028, &
+        2.44565251e+020,4.74227538e+030,10497312.0e0000,7.74079654e-039/
 
   n2=(n1-NTAPS+NDOWN)/NDOWN
   k0=NH-NDOWN+1