diff --git a/CMakeLists.txt b/CMakeLists.txt
index 6f15763..7042db5 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -19,7 +19,7 @@ include(FetchContent)
 FetchContent_Declare(
         absl
         GIT_REPOSITORY https://github.com/abseil/abseil-cpp.git
-        GIT_TAG d38452e1ee03523a208362186fd42248ff2609f6
+        GIT_TAG 20250512.1
 )
 FetchContent_MakeAvailable(absl)
 
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_ambient_l.cc b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_ambient_l.cc
index 6451605..66b45d7 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_ambient_l.cc
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_ambient_l.cc
@@ -8,14 +8,14 @@
 
 #include "binaural_filters_1_oa_ambient_l.h"
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
 // clang-format off
-std::vector<unsigned char> BinauralFilters1OAAmbientL() {
-  return {
+std::span<const unsigned char> BinauralFilters1OAAmbientL() {
+  static const unsigned char kDataArray[] = {
       0x52, 0x49, 0x46, 0x46, 0x24, 0x00, 0x01, 0x00, 0x57, 0x41, 0x56, 0x45,
       0x66, 0x6d, 0x74, 0x20, 0x10, 0x00, 0x00, 0x00, 0x01, 0x00, 0x04, 0x00,
       0x80, 0xbb, 0x00, 0x00, 0x00, 0xdc, 0x05, 0x00, 0x08, 0x00, 0x10, 0x00,
@@ -5482,6 +5482,7 @@ std::vector<unsigned char> BinauralFilters1OAAmbientL() {
       0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0xff, 0xff,
       0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
   };
+  return kDataArray;
 }
 // clang-format on
 
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_ambient_l.h b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_ambient_l.h
index 9860167..c3e344c 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_ambient_l.h
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_ambient_l.h
@@ -9,12 +9,12 @@
 #ifndef BINAURAL_FILTERS_1_OA_AMBIENT_L_H_
 #define BINAURAL_FILTERS_1_OA_AMBIENT_L_H_
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
-std::vector<unsigned char> BinauralFilters1OAAmbientL();
+std::span<const unsigned char> BinauralFilters1OAAmbientL();
 
 }  // namespace filter_files
 }  // namespace obr
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_ambient_r.cc b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_ambient_r.cc
index 494cb97..74ad942 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_ambient_r.cc
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_ambient_r.cc
@@ -8,14 +8,14 @@
 
 #include "binaural_filters_1_oa_ambient_r.h"
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
 // clang-format off
-std::vector<unsigned char> BinauralFilters1OAAmbientR() {
-  return {
+std::span<const unsigned char> BinauralFilters1OAAmbientR() {
+  static const unsigned char kDataArray[] = {
       0x52, 0x49, 0x46, 0x46, 0x24, 0x00, 0x01, 0x00, 0x57, 0x41, 0x56, 0x45,
       0x66, 0x6d, 0x74, 0x20, 0x10, 0x00, 0x00, 0x00, 0x01, 0x00, 0x04, 0x00,
       0x80, 0xbb, 0x00, 0x00, 0x00, 0xdc, 0x05, 0x00, 0x08, 0x00, 0x10, 0x00,
@@ -5482,6 +5482,7 @@ std::vector<unsigned char> BinauralFilters1OAAmbientR() {
       0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff,
       0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00,
   };
+  return kDataArray;
 }
 // clang-format on
 
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_ambient_r.h b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_ambient_r.h
index a302d45..83217fb 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_ambient_r.h
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_ambient_r.h
@@ -9,12 +9,12 @@
 #ifndef BINAURAL_FILTERS_1_OA_AMBIENT_R_H_
 #define BINAURAL_FILTERS_1_OA_AMBIENT_R_H_
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
-std::vector<unsigned char> BinauralFilters1OAAmbientR();
+std::span<const unsigned char> BinauralFilters1OAAmbientR();
 
 }  // namespace filter_files
 }  // namespace obr
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_direct_l.cc b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_direct_l.cc
index 4b4c322..7930a24 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_direct_l.cc
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_direct_l.cc
@@ -8,14 +8,14 @@
 
 #include "binaural_filters_1_oa_direct_l.h"
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
 // clang-format off
-std::vector<unsigned char> BinauralFilters1OADirectL() {
-  return {
+std::span<const unsigned char> BinauralFilters1OADirectL() {
+  static const unsigned char kDataArray[] = {
       0x52, 0x49, 0x46, 0x46, 0x24, 0x08, 0x00, 0x00, 0x57, 0x41, 0x56, 0x45,
       0x66, 0x6d, 0x74, 0x20, 0x10, 0x00, 0x00, 0x00, 0x01, 0x00, 0x04, 0x00,
       0x80, 0xbb, 0x00, 0x00, 0x00, 0xdc, 0x05, 0x00, 0x08, 0x00, 0x10, 0x00,
@@ -192,6 +192,7 @@ std::vector<unsigned char> BinauralFilters1OADirectL() {
       0xfe, 0xff, 0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0xfe, 0xff, 0x00, 0x00,
       0xff, 0xff, 0x00, 0x00,
   };
+  return kDataArray;
 }
 // clang-format on
 
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_direct_l.h b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_direct_l.h
index b1fa30a..cf51331 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_direct_l.h
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_direct_l.h
@@ -9,12 +9,12 @@
 #ifndef BINAURAL_FILTERS_1_OA_DIRECT_L_H_
 #define BINAURAL_FILTERS_1_OA_DIRECT_L_H_
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
-std::vector<unsigned char> BinauralFilters1OADirectL();
+std::span<const unsigned char> BinauralFilters1OADirectL();
 
 }  // namespace filter_files
 }  // namespace obr
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_direct_r.cc b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_direct_r.cc
index d8f4829..2acdef7 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_direct_r.cc
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_direct_r.cc
@@ -8,14 +8,14 @@
 
 #include "binaural_filters_1_oa_direct_r.h"
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
 // clang-format off
-std::vector<unsigned char> BinauralFilters1OADirectR() {
-  return {
+std::span<const unsigned char> BinauralFilters1OADirectR() {
+  static const unsigned char kDataArray[] = {
       0x52, 0x49, 0x46, 0x46, 0x24, 0x08, 0x00, 0x00, 0x57, 0x41, 0x56, 0x45,
       0x66, 0x6d, 0x74, 0x20, 0x10, 0x00, 0x00, 0x00, 0x01, 0x00, 0x04, 0x00,
       0x80, 0xbb, 0x00, 0x00, 0x00, 0xdc, 0x05, 0x00, 0x08, 0x00, 0x10, 0x00,
@@ -192,6 +192,7 @@ std::vector<unsigned char> BinauralFilters1OADirectR() {
       0xfe, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0xfe, 0xff, 0xff, 0xff,
       0xff, 0xff, 0x00, 0x00,
   };
+  return kDataArray;
 }
 // clang-format on
 
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_direct_r.h b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_direct_r.h
index 42e1559..5e4a688 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_direct_r.h
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_direct_r.h
@@ -9,12 +9,12 @@
 #ifndef BINAURAL_FILTERS_1_OA_DIRECT_R_H_
 #define BINAURAL_FILTERS_1_OA_DIRECT_R_H_
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
-std::vector<unsigned char> BinauralFilters1OADirectR();
+std::span<const unsigned char> BinauralFilters1OADirectR();
 
 }  // namespace filter_files
 }  // namespace obr
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_reverberant_l.cc b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_reverberant_l.cc
index b73c93f..9ae9ef6 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_reverberant_l.cc
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_reverberant_l.cc
@@ -8,14 +8,14 @@
 
 #include "binaural_filters_1_oa_reverberant_l.h"
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
 // clang-format off
-std::vector<unsigned char> BinauralFilters1OAReverberantL() {
-  return {
+std::span<const unsigned char> BinauralFilters1OAReverberantL() {
+  static const unsigned char kDataArray[] = {
       0x52, 0x49, 0x46, 0x46, 0x24, 0x00, 0x01, 0x00, 0x57, 0x41, 0x56, 0x45,
       0x66, 0x6d, 0x74, 0x20, 0x10, 0x00, 0x00, 0x00, 0x01, 0x00, 0x04, 0x00,
       0x80, 0xbb, 0x00, 0x00, 0x00, 0xdc, 0x05, 0x00, 0x08, 0x00, 0x10, 0x00,
@@ -5482,6 +5482,7 @@ std::vector<unsigned char> BinauralFilters1OAReverberantL() {
       0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0xff, 0xff,
       0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
   };
+  return kDataArray;
 }
 // clang-format on
 
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_reverberant_l.h b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_reverberant_l.h
index 974c6a2..fc431e6 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_reverberant_l.h
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_reverberant_l.h
@@ -9,12 +9,12 @@
 #ifndef BINAURAL_FILTERS_1_OA_REVERBERANT_L_H_
 #define BINAURAL_FILTERS_1_OA_REVERBERANT_L_H_
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
-std::vector<unsigned char> BinauralFilters1OAReverberantL();
+std::span<const unsigned char> BinauralFilters1OAReverberantL();
 
 }  // namespace filter_files
 }  // namespace obr
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_reverberant_r.cc b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_reverberant_r.cc
index ae488cf..80cc0f5 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_reverberant_r.cc
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_reverberant_r.cc
@@ -8,14 +8,14 @@
 
 #include "binaural_filters_1_oa_reverberant_r.h"
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
 // clang-format off
-std::vector<unsigned char> BinauralFilters1OAReverberantR() {
-  return {
+std::span<const unsigned char> BinauralFilters1OAReverberantR() {
+  static const unsigned char kDataArray[] = {
       0x52, 0x49, 0x46, 0x46, 0x24, 0x00, 0x01, 0x00, 0x57, 0x41, 0x56, 0x45,
       0x66, 0x6d, 0x74, 0x20, 0x10, 0x00, 0x00, 0x00, 0x01, 0x00, 0x04, 0x00,
       0x80, 0xbb, 0x00, 0x00, 0x00, 0xdc, 0x05, 0x00, 0x08, 0x00, 0x10, 0x00,
@@ -5482,6 +5482,7 @@ std::vector<unsigned char> BinauralFilters1OAReverberantR() {
       0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff,
       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00,
   };
+  return kDataArray;
 }
 // clang-format on
 
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_reverberant_r.h b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_reverberant_r.h
index 78a7c4a..4b80af7 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_reverberant_r.h
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_1_oa_reverberant_r.h
@@ -9,12 +9,12 @@
 #ifndef BINAURAL_FILTERS_1_OA_REVERBERANT_R_H_
 #define BINAURAL_FILTERS_1_OA_REVERBERANT_R_H_
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
-std::vector<unsigned char> BinauralFilters1OAReverberantR();
+std::span<const unsigned char> BinauralFilters1OAReverberantR();
 
 }  // namespace filter_files
 }  // namespace obr
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_ambient_l.cc b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_ambient_l.cc
index fadbf00..21cf327 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_ambient_l.cc
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_ambient_l.cc
@@ -8,14 +8,14 @@
 
 #include "binaural_filters_2_oa_ambient_l.h"
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
 // clang-format off
-std::vector<unsigned char> BinauralFilters2OAAmbientL() {
-  return {
+std::span<const unsigned char> BinauralFilters2OAAmbientL() {
+  static const unsigned char kDataArray[] = {
       0x52, 0x49, 0x46, 0x46, 0x24, 0x40, 0x02, 0x00, 0x57, 0x41, 0x56, 0x45,
       0x66, 0x6d, 0x74, 0x20, 0x10, 0x00, 0x00, 0x00, 0x01, 0x00, 0x09, 0x00,
       0x80, 0xbb, 0x00, 0x00, 0x00, 0x2f, 0x0d, 0x00, 0x12, 0x00, 0x10, 0x00,
@@ -12309,6 +12309,7 @@ std::vector<unsigned char> BinauralFilters2OAAmbientL() {
       0xff, 0xff, 0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0xff, 0xff, 0x00, 0x00,
       0xff, 0xff, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff,
   };
+  return kDataArray;
 }
 // clang-format on
 
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_ambient_l.h b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_ambient_l.h
index 2d280ba..8bf16cd 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_ambient_l.h
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_ambient_l.h
@@ -9,12 +9,12 @@
 #ifndef BINAURAL_FILTERS_2_OA_AMBIENT_L_H_
 #define BINAURAL_FILTERS_2_OA_AMBIENT_L_H_
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
-std::vector<unsigned char> BinauralFilters2OAAmbientL();
+std::span<const unsigned char> BinauralFilters2OAAmbientL();
 
 }  // namespace filter_files
 }  // namespace obr
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_ambient_r.cc b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_ambient_r.cc
index 1981d62..d093e42 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_ambient_r.cc
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_ambient_r.cc
@@ -8,14 +8,14 @@
 
 #include "binaural_filters_2_oa_ambient_r.h"
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
 // clang-format off
-std::vector<unsigned char> BinauralFilters2OAAmbientR() {
-  return {
+std::span<const unsigned char> BinauralFilters2OAAmbientR() {
+  static const unsigned char kDataArray[] = {
       0x52, 0x49, 0x46, 0x46, 0x24, 0x40, 0x02, 0x00, 0x57, 0x41, 0x56, 0x45,
       0x66, 0x6d, 0x74, 0x20, 0x10, 0x00, 0x00, 0x00, 0x01, 0x00, 0x09, 0x00,
       0x80, 0xbb, 0x00, 0x00, 0x00, 0x2f, 0x0d, 0x00, 0x12, 0x00, 0x10, 0x00,
@@ -12309,6 +12309,7 @@ std::vector<unsigned char> BinauralFilters2OAAmbientR() {
       0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
       0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00,
   };
+  return kDataArray;
 }
 // clang-format on
 
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_ambient_r.h b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_ambient_r.h
index bcfd465..f51877a 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_ambient_r.h
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_ambient_r.h
@@ -9,12 +9,12 @@
 #ifndef BINAURAL_FILTERS_2_OA_AMBIENT_R_H_
 #define BINAURAL_FILTERS_2_OA_AMBIENT_R_H_
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
-std::vector<unsigned char> BinauralFilters2OAAmbientR();
+std::span<const unsigned char> BinauralFilters2OAAmbientR();
 
 }  // namespace filter_files
 }  // namespace obr
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_direct_l.cc b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_direct_l.cc
index fd83fd4..a4cfb91 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_direct_l.cc
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_direct_l.cc
@@ -8,14 +8,14 @@
 
 #include "binaural_filters_2_oa_direct_l.h"
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
 // clang-format off
-std::vector<unsigned char> BinauralFilters2OADirectL() {
-  return {
+std::span<const unsigned char> BinauralFilters2OADirectL() {
+  static const unsigned char kDataArray[] = {
       0x52, 0x49, 0x46, 0x46, 0x24, 0x12, 0x00, 0x00, 0x57, 0x41, 0x56, 0x45,
       0x66, 0x6d, 0x74, 0x20, 0x10, 0x00, 0x00, 0x00, 0x01, 0x00, 0x09, 0x00,
       0x80, 0xbb, 0x00, 0x00, 0x00, 0x2f, 0x0d, 0x00, 0x12, 0x00, 0x10, 0x00,
@@ -405,6 +405,7 @@ std::vector<unsigned char> BinauralFilters2OADirectL() {
       0x01, 0x00, 0xfd, 0xff, 0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0xff, 0xff,
       0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff,
   };
+  return kDataArray;
 }
 // clang-format on
 
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_direct_l.h b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_direct_l.h
index b6eef64..5ae8ac7 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_direct_l.h
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_direct_l.h
@@ -9,12 +9,12 @@
 #ifndef BINAURAL_FILTERS_2_OA_DIRECT_L_H_
 #define BINAURAL_FILTERS_2_OA_DIRECT_L_H_
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
-std::vector<unsigned char> BinauralFilters2OADirectL();
+std::span<const unsigned char> BinauralFilters2OADirectL();
 
 }  // namespace filter_files
 }  // namespace obr
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_direct_r.cc b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_direct_r.cc
index d520695..afbaeb7 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_direct_r.cc
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_direct_r.cc
@@ -8,14 +8,14 @@
 
 #include "binaural_filters_2_oa_direct_r.h"
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
 // clang-format off
-std::vector<unsigned char> BinauralFilters2OADirectR() {
-  return {
+std::span<const unsigned char> BinauralFilters2OADirectR() {
+  static const unsigned char kDataArray[] = {
       0x52, 0x49, 0x46, 0x46, 0x24, 0x12, 0x00, 0x00, 0x57, 0x41, 0x56, 0x45,
       0x66, 0x6d, 0x74, 0x20, 0x10, 0x00, 0x00, 0x00, 0x01, 0x00, 0x09, 0x00,
       0x80, 0xbb, 0x00, 0x00, 0x00, 0x2f, 0x0d, 0x00, 0x12, 0x00, 0x10, 0x00,
@@ -405,6 +405,7 @@ std::vector<unsigned char> BinauralFilters2OADirectR() {
       0x01, 0x00, 0xfd, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00,
       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff,
   };
+  return kDataArray;
 }
 // clang-format on
 
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_direct_r.h b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_direct_r.h
index 382af8c..c334349 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_direct_r.h
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_direct_r.h
@@ -9,12 +9,12 @@
 #ifndef BINAURAL_FILTERS_2_OA_DIRECT_R_H_
 #define BINAURAL_FILTERS_2_OA_DIRECT_R_H_
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
-std::vector<unsigned char> BinauralFilters2OADirectR();
+std::span<const unsigned char> BinauralFilters2OADirectR();
 
 }  // namespace filter_files
 }  // namespace obr
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_reverberant_l.cc b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_reverberant_l.cc
index 7e16481..bbeb5db 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_reverberant_l.cc
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_reverberant_l.cc
@@ -8,14 +8,14 @@
 
 #include "binaural_filters_2_oa_reverberant_l.h"
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
 // clang-format off
-std::vector<unsigned char> BinauralFilters2OAReverberantL() {
-  return {
+std::span<const unsigned char> BinauralFilters2OAReverberantL() {
+  static const unsigned char kDataArray[] = {
       0x52, 0x49, 0x46, 0x46, 0x24, 0x40, 0x02, 0x00, 0x57, 0x41, 0x56, 0x45,
       0x66, 0x6d, 0x74, 0x20, 0x10, 0x00, 0x00, 0x00, 0x01, 0x00, 0x09, 0x00,
       0x80, 0xbb, 0x00, 0x00, 0x00, 0x2f, 0x0d, 0x00, 0x12, 0x00, 0x10, 0x00,
@@ -12309,6 +12309,7 @@ std::vector<unsigned char> BinauralFilters2OAReverberantL() {
       0xff, 0xff, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00,
       0xff, 0xff, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff,
   };
+  return kDataArray;
 }
 // clang-format on
 
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_reverberant_l.h b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_reverberant_l.h
index 47fb177..add5fb6 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_reverberant_l.h
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_reverberant_l.h
@@ -9,12 +9,12 @@
 #ifndef BINAURAL_FILTERS_2_OA_REVERBERANT_L_H_
 #define BINAURAL_FILTERS_2_OA_REVERBERANT_L_H_
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
-std::vector<unsigned char> BinauralFilters2OAReverberantL();
+std::span<const unsigned char> BinauralFilters2OAReverberantL();
 
 }  // namespace filter_files
 }  // namespace obr
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_reverberant_r.cc b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_reverberant_r.cc
index 07f9af0..7544c6f 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_reverberant_r.cc
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_reverberant_r.cc
@@ -8,14 +8,14 @@
 
 #include "binaural_filters_2_oa_reverberant_r.h"
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
 // clang-format off
-std::vector<unsigned char> BinauralFilters2OAReverberantR() {
-  return {
+std::span<const unsigned char> BinauralFilters2OAReverberantR() {
+  static const unsigned char kDataArray[] = {
       0x52, 0x49, 0x46, 0x46, 0x24, 0x40, 0x02, 0x00, 0x57, 0x41, 0x56, 0x45,
       0x66, 0x6d, 0x74, 0x20, 0x10, 0x00, 0x00, 0x00, 0x01, 0x00, 0x09, 0x00,
       0x80, 0xbb, 0x00, 0x00, 0x00, 0x2f, 0x0d, 0x00, 0x12, 0x00, 0x10, 0x00,
@@ -12309,6 +12309,7 @@ std::vector<unsigned char> BinauralFilters2OAReverberantR() {
       0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
       0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00,
   };
+  return kDataArray;
 }
 // clang-format on
 
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_reverberant_r.h b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_reverberant_r.h
index b2d91a3..81d10e6 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_reverberant_r.h
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_2_oa_reverberant_r.h
@@ -9,12 +9,12 @@
 #ifndef BINAURAL_FILTERS_2_OA_REVERBERANT_R_H_
 #define BINAURAL_FILTERS_2_OA_REVERBERANT_R_H_
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
-std::vector<unsigned char> BinauralFilters2OAReverberantR();
+std::span<const unsigned char> BinauralFilters2OAReverberantR();
 
 }  // namespace filter_files
 }  // namespace obr
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_ambient_l.cc b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_ambient_l.cc
index 176b2d3..e07d92c 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_ambient_l.cc
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_ambient_l.cc
@@ -8,14 +8,14 @@
 
 #include "binaural_filters_3_oa_ambient_l.h"
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
 // clang-format off
-std::vector<unsigned char> BinauralFilters3OAAmbientL() {
-  return {
+std::span<const unsigned char> BinauralFilters3OAAmbientL() {
+  static const unsigned char kDataArray[] = {
       0x52, 0x49, 0x46, 0x46, 0x24, 0x00, 0x04, 0x00, 0x57, 0x41, 0x56, 0x45,
       0x66, 0x6d, 0x74, 0x20, 0x10, 0x00, 0x00, 0x00, 0x01, 0x00, 0x10, 0x00,
       0x80, 0xbb, 0x00, 0x00, 0x00, 0x70, 0x17, 0x00, 0x20, 0x00, 0x10, 0x00,
@@ -21866,6 +21866,7 @@ std::vector<unsigned char> BinauralFilters3OAAmbientL() {
       0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
       0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00,
   };
+  return kDataArray;
 }
 // clang-format on
 
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_ambient_l.h b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_ambient_l.h
index c5aab70..78dccad 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_ambient_l.h
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_ambient_l.h
@@ -9,12 +9,12 @@
 #ifndef BINAURAL_FILTERS_3_OA_AMBIENT_L_H_
 #define BINAURAL_FILTERS_3_OA_AMBIENT_L_H_
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
-std::vector<unsigned char> BinauralFilters3OAAmbientL();
+std::span<const unsigned char> BinauralFilters3OAAmbientL();
 
 }  // namespace filter_files
 }  // namespace obr
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_ambient_r.cc b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_ambient_r.cc
index 72ada3b..e50d74a 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_ambient_r.cc
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_ambient_r.cc
@@ -8,14 +8,14 @@
 
 #include "binaural_filters_3_oa_ambient_r.h"
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
 // clang-format off
-std::vector<unsigned char> BinauralFilters3OAAmbientR() {
-  return {
+std::span<const unsigned char> BinauralFilters3OAAmbientR() {
+  static const unsigned char kDataArray[] = {
       0x52, 0x49, 0x46, 0x46, 0x24, 0x00, 0x04, 0x00, 0x57, 0x41, 0x56, 0x45,
       0x66, 0x6d, 0x74, 0x20, 0x10, 0x00, 0x00, 0x00, 0x01, 0x00, 0x10, 0x00,
       0x80, 0xbb, 0x00, 0x00, 0x00, 0x70, 0x17, 0x00, 0x20, 0x00, 0x10, 0x00,
@@ -21866,6 +21866,7 @@ std::vector<unsigned char> BinauralFilters3OAAmbientR() {
       0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff,
       0xff, 0xff, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
   };
+  return kDataArray;
 }
 // clang-format on
 
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_ambient_r.h b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_ambient_r.h
index 346f78d..acb3aeb 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_ambient_r.h
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_ambient_r.h
@@ -9,12 +9,12 @@
 #ifndef BINAURAL_FILTERS_3_OA_AMBIENT_R_H_
 #define BINAURAL_FILTERS_3_OA_AMBIENT_R_H_
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
-std::vector<unsigned char> BinauralFilters3OAAmbientR();
+std::span<const unsigned char> BinauralFilters3OAAmbientR();
 
 }  // namespace filter_files
 }  // namespace obr
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_direct_l.cc b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_direct_l.cc
index 1f86a36..9b32f1b 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_direct_l.cc
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_direct_l.cc
@@ -8,14 +8,14 @@
 
 #include "binaural_filters_3_oa_direct_l.h"
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
 // clang-format off
-std::vector<unsigned char> BinauralFilters3OADirectL() {
-  return {
+std::span<const unsigned char> BinauralFilters3OADirectL() {
+  static const unsigned char kDataArray[] = {
       0x52, 0x49, 0x46, 0x46, 0x24, 0x20, 0x00, 0x00, 0x57, 0x41, 0x56, 0x45,
       0x66, 0x6d, 0x74, 0x20, 0x10, 0x00, 0x00, 0x00, 0x01, 0x00, 0x10, 0x00,
       0x80, 0xbb, 0x00, 0x00, 0x00, 0x70, 0x17, 0x00, 0x20, 0x00, 0x10, 0x00,
@@ -704,6 +704,7 @@ std::vector<unsigned char> BinauralFilters3OADirectL() {
       0xfe, 0xff, 0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
       0xff, 0xff, 0xff, 0xff,
   };
+  return kDataArray;
 }
 // clang-format on
 
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_direct_l.h b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_direct_l.h
index 3560946..6c3f8d0 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_direct_l.h
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_direct_l.h
@@ -9,12 +9,12 @@
 #ifndef BINAURAL_FILTERS_3_OA_DIRECT_L_H_
 #define BINAURAL_FILTERS_3_OA_DIRECT_L_H_
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
-std::vector<unsigned char> BinauralFilters3OADirectL();
+std::span<const unsigned char> BinauralFilters3OADirectL();
 
 }  // namespace filter_files
 }  // namespace obr
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_direct_r.cc b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_direct_r.cc
index bea349f..0a36f6d 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_direct_r.cc
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_direct_r.cc
@@ -8,14 +8,14 @@
 
 #include "binaural_filters_3_oa_direct_r.h"
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
 // clang-format off
-std::vector<unsigned char> BinauralFilters3OADirectR() {
-  return {
+std::span<const unsigned char> BinauralFilters3OADirectR() {
+  static const unsigned char kDataArray[] = {
       0x52, 0x49, 0x46, 0x46, 0x24, 0x20, 0x00, 0x00, 0x57, 0x41, 0x56, 0x45,
       0x66, 0x6d, 0x74, 0x20, 0x10, 0x00, 0x00, 0x00, 0x01, 0x00, 0x10, 0x00,
       0x80, 0xbb, 0x00, 0x00, 0x00, 0x70, 0x17, 0x00, 0x20, 0x00, 0x10, 0x00,
@@ -704,6 +704,7 @@ std::vector<unsigned char> BinauralFilters3OADirectR() {
       0xfe, 0xff, 0xff, 0xff, 0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00,
       0xff, 0xff, 0xff, 0xff,
   };
+  return kDataArray;
 }
 // clang-format on
 
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_direct_r.h b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_direct_r.h
index ebcb0c3..a33a0a7 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_direct_r.h
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_direct_r.h
@@ -9,12 +9,12 @@
 #ifndef BINAURAL_FILTERS_3_OA_DIRECT_R_H_
 #define BINAURAL_FILTERS_3_OA_DIRECT_R_H_
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
-std::vector<unsigned char> BinauralFilters3OADirectR();
+std::span<const unsigned char> BinauralFilters3OADirectR();
 
 }  // namespace filter_files
 }  // namespace obr
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_reverberant_l.cc b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_reverberant_l.cc
index 7817821..7ff947a 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_reverberant_l.cc
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_reverberant_l.cc
@@ -8,14 +8,14 @@
 
 #include "binaural_filters_3_oa_reverberant_l.h"
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
 // clang-format off
-std::vector<unsigned char> BinauralFilters3OAReverberantL() {
-  return {
+std::span<const unsigned char> BinauralFilters3OAReverberantL() {
+  static const unsigned char kDataArray[] = {
       0x52, 0x49, 0x46, 0x46, 0x24, 0x00, 0x04, 0x00, 0x57, 0x41, 0x56, 0x45,
       0x66, 0x6d, 0x74, 0x20, 0x10, 0x00, 0x00, 0x00, 0x01, 0x00, 0x10, 0x00,
       0x80, 0xbb, 0x00, 0x00, 0x00, 0x70, 0x17, 0x00, 0x20, 0x00, 0x10, 0x00,
@@ -21866,6 +21866,7 @@ std::vector<unsigned char> BinauralFilters3OAReverberantL() {
       0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
       0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
   };
+  return kDataArray;
 }
 // clang-format on
 
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_reverberant_l.h b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_reverberant_l.h
index cb17302..bd24fcb 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_reverberant_l.h
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_reverberant_l.h
@@ -9,12 +9,12 @@
 #ifndef BINAURAL_FILTERS_3_OA_REVERBERANT_L_H_
 #define BINAURAL_FILTERS_3_OA_REVERBERANT_L_H_
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
-std::vector<unsigned char> BinauralFilters3OAReverberantL();
+std::span<const unsigned char> BinauralFilters3OAReverberantL();
 
 }  // namespace filter_files
 }  // namespace obr
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_reverberant_r.cc b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_reverberant_r.cc
index 14fcf64..5a3db55 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_reverberant_r.cc
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_reverberant_r.cc
@@ -8,14 +8,14 @@
 
 #include "binaural_filters_3_oa_reverberant_r.h"
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
 // clang-format off
-std::vector<unsigned char> BinauralFilters3OAReverberantR() {
-  return {
+std::span<const unsigned char> BinauralFilters3OAReverberantR() {
+  static const unsigned char kDataArray[] = {
       0x52, 0x49, 0x46, 0x46, 0x24, 0x00, 0x04, 0x00, 0x57, 0x41, 0x56, 0x45,
       0x66, 0x6d, 0x74, 0x20, 0x10, 0x00, 0x00, 0x00, 0x01, 0x00, 0x10, 0x00,
       0x80, 0xbb, 0x00, 0x00, 0x00, 0x70, 0x17, 0x00, 0x20, 0x00, 0x10, 0x00,
@@ -21866,6 +21866,7 @@ std::vector<unsigned char> BinauralFilters3OAReverberantR() {
       0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff,
       0xff, 0xff, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
   };
+  return kDataArray;
 }
 // clang-format on
 
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_reverberant_r.h b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_reverberant_r.h
index 5a808c4..97d1131 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_reverberant_r.h
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_3_oa_reverberant_r.h
@@ -9,12 +9,12 @@
 #ifndef BINAURAL_FILTERS_3_OA_REVERBERANT_R_H_
 #define BINAURAL_FILTERS_3_OA_REVERBERANT_R_H_
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
-std::vector<unsigned char> BinauralFilters3OAReverberantR();
+std::span<const unsigned char> BinauralFilters3OAReverberantR();
 
 }  // namespace filter_files
 }  // namespace obr
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_ambient_l.cc b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_ambient_l.cc
index a8daa87..ced0366 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_ambient_l.cc
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_ambient_l.cc
@@ -8,14 +8,14 @@
 
 #include "binaural_filters_4_oa_ambient_l.h"
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
 // clang-format off
-std::vector<unsigned char> BinauralFilters4OAAmbientL() {
-  return {
+std::span<const unsigned char> BinauralFilters4OAAmbientL() {
+  static const unsigned char kDataArray[] = {
       0x52, 0x49, 0x46, 0x46, 0x24, 0x40, 0x06, 0x00, 0x57, 0x41, 0x56, 0x45,
       0x66, 0x6d, 0x74, 0x20, 0x10, 0x00, 0x00, 0x00, 0x01, 0x00, 0x19, 0x00,
       0x80, 0xbb, 0x00, 0x00, 0x00, 0x9f, 0x24, 0x00, 0x32, 0x00, 0x10, 0x00,
@@ -34154,6 +34154,7 @@ std::vector<unsigned char> BinauralFilters4OAAmbientL() {
       0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00,
       0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff,
   };
+  return kDataArray;
 }
 // clang-format on
 
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_ambient_l.h b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_ambient_l.h
index 3013a45..e6bc060 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_ambient_l.h
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_ambient_l.h
@@ -9,12 +9,12 @@
 #ifndef BINAURAL_FILTERS_4_OA_AMBIENT_L_H_
 #define BINAURAL_FILTERS_4_OA_AMBIENT_L_H_
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
-std::vector<unsigned char> BinauralFilters4OAAmbientL();
+std::span<const unsigned char> BinauralFilters4OAAmbientL();
 
 }  // namespace filter_files
 }  // namespace obr
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_ambient_r.cc b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_ambient_r.cc
index b3fc4cc..7e1b652 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_ambient_r.cc
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_ambient_r.cc
@@ -8,14 +8,14 @@
 
 #include "binaural_filters_4_oa_ambient_r.h"
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
 // clang-format off
-std::vector<unsigned char> BinauralFilters4OAAmbientR() {
-  return {
+std::span<const unsigned char> BinauralFilters4OAAmbientR() {
+  static const unsigned char kDataArray[] = {
       0x52, 0x49, 0x46, 0x46, 0x24, 0x40, 0x06, 0x00, 0x57, 0x41, 0x56, 0x45,
       0x66, 0x6d, 0x74, 0x20, 0x10, 0x00, 0x00, 0x00, 0x01, 0x00, 0x19, 0x00,
       0x80, 0xbb, 0x00, 0x00, 0x00, 0x9f, 0x24, 0x00, 0x32, 0x00, 0x10, 0x00,
@@ -34154,6 +34154,7 @@ std::vector<unsigned char> BinauralFilters4OAAmbientR() {
       0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0x00, 0x00,
       0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff,
   };
+  return kDataArray;
 }
 // clang-format on
 
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_ambient_r.h b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_ambient_r.h
index 6bb5233..0f0c2fc 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_ambient_r.h
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_ambient_r.h
@@ -9,12 +9,12 @@
 #ifndef BINAURAL_FILTERS_4_OA_AMBIENT_R_H_
 #define BINAURAL_FILTERS_4_OA_AMBIENT_R_H_
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
-std::vector<unsigned char> BinauralFilters4OAAmbientR();
+std::span<const unsigned char> BinauralFilters4OAAmbientR();
 
 }  // namespace filter_files
 }  // namespace obr
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_direct_l.cc b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_direct_l.cc
index 97a361d..ab0e2e4 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_direct_l.cc
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_direct_l.cc
@@ -8,14 +8,14 @@
 
 #include "binaural_filters_4_oa_direct_l.h"
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
 // clang-format off
-std::vector<unsigned char> BinauralFilters4OADirectL() {
-  return {
+std::span<const unsigned char> BinauralFilters4OADirectL() {
+  static const unsigned char kDataArray[] = {
       0x52, 0x49, 0x46, 0x46, 0x24, 0x32, 0x00, 0x00, 0x57, 0x41, 0x56, 0x45,
       0x66, 0x6d, 0x74, 0x20, 0x10, 0x00, 0x00, 0x00, 0x01, 0x00, 0x19, 0x00,
       0x80, 0xbb, 0x00, 0x00, 0x00, 0x9f, 0x24, 0x00, 0x32, 0x00, 0x10, 0x00,
@@ -1088,6 +1088,7 @@ std::vector<unsigned char> BinauralFilters4OADirectL() {
       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff,
       0xff, 0xff, 0xff, 0xff,
   };
+  return kDataArray;
 }
 // clang-format on
 
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_direct_l.h b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_direct_l.h
index e6825b8..de73a5a 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_direct_l.h
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_direct_l.h
@@ -9,12 +9,12 @@
 #ifndef BINAURAL_FILTERS_4_OA_DIRECT_L_H_
 #define BINAURAL_FILTERS_4_OA_DIRECT_L_H_
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
-std::vector<unsigned char> BinauralFilters4OADirectL();
+std::span<const unsigned char> BinauralFilters4OADirectL();
 
 }  // namespace filter_files
 }  // namespace obr
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_direct_r.cc b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_direct_r.cc
index 41348be..3458aec 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_direct_r.cc
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_direct_r.cc
@@ -8,14 +8,14 @@
 
 #include "binaural_filters_4_oa_direct_r.h"
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
 // clang-format off
-std::vector<unsigned char> BinauralFilters4OADirectR() {
-  return {
+std::span<const unsigned char> BinauralFilters4OADirectR() {
+  static const unsigned char kDataArray[] = {
       0x52, 0x49, 0x46, 0x46, 0x24, 0x32, 0x00, 0x00, 0x57, 0x41, 0x56, 0x45,
       0x66, 0x6d, 0x74, 0x20, 0x10, 0x00, 0x00, 0x00, 0x01, 0x00, 0x19, 0x00,
       0x80, 0xbb, 0x00, 0x00, 0x00, 0x9f, 0x24, 0x00, 0x32, 0x00, 0x10, 0x00,
@@ -1088,6 +1088,7 @@ std::vector<unsigned char> BinauralFilters4OADirectR() {
       0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0xff, 0x00, 0x00, 0xff, 0xff,
       0x00, 0x00, 0xff, 0xff,
   };
+  return kDataArray;
 }
 // clang-format on
 
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_direct_r.h b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_direct_r.h
index a1fcb62..5d2ff83 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_direct_r.h
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_direct_r.h
@@ -9,12 +9,12 @@
 #ifndef BINAURAL_FILTERS_4_OA_DIRECT_R_H_
 #define BINAURAL_FILTERS_4_OA_DIRECT_R_H_
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
-std::vector<unsigned char> BinauralFilters4OADirectR();
+std::span<const unsigned char> BinauralFilters4OADirectR();
 
 }  // namespace filter_files
 }  // namespace obr
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_reverberant_l.cc b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_reverberant_l.cc
index 3e5daef..6e7b0d3 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_reverberant_l.cc
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_reverberant_l.cc
@@ -8,14 +8,14 @@
 
 #include "binaural_filters_4_oa_reverberant_l.h"
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
 // clang-format off
-std::vector<unsigned char> BinauralFilters4OAReverberantL() {
-  return {
+std::span<const unsigned char> BinauralFilters4OAReverberantL() {
+  static const unsigned char kDataArray[] = {
       0x52, 0x49, 0x46, 0x46, 0x24, 0x40, 0x06, 0x00, 0x57, 0x41, 0x56, 0x45,
       0x66, 0x6d, 0x74, 0x20, 0x10, 0x00, 0x00, 0x00, 0x01, 0x00, 0x19, 0x00,
       0x80, 0xbb, 0x00, 0x00, 0x00, 0x9f, 0x24, 0x00, 0x32, 0x00, 0x10, 0x00,
@@ -34154,6 +34154,7 @@ std::vector<unsigned char> BinauralFilters4OAReverberantL() {
       0x00, 0x00, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00,
       0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0x00, 0x00,
   };
+  return kDataArray;
 }
 // clang-format on
 
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_reverberant_l.h b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_reverberant_l.h
index 71b3fed..852ec4b 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_reverberant_l.h
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_reverberant_l.h
@@ -9,12 +9,12 @@
 #ifndef BINAURAL_FILTERS_4_OA_REVERBERANT_L_H_
 #define BINAURAL_FILTERS_4_OA_REVERBERANT_L_H_
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
-std::vector<unsigned char> BinauralFilters4OAReverberantL();
+std::span<const unsigned char> BinauralFilters4OAReverberantL();
 
 }  // namespace filter_files
 }  // namespace obr
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_reverberant_r.cc b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_reverberant_r.cc
index 176170a..6e7cbfb 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_reverberant_r.cc
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_reverberant_r.cc
@@ -8,14 +8,14 @@
 
 #include "binaural_filters_4_oa_reverberant_r.h"
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
 // clang-format off
-std::vector<unsigned char> BinauralFilters4OAReverberantR() {
-  return {
+std::span<const unsigned char> BinauralFilters4OAReverberantR() {
+  static const unsigned char kDataArray[] = {
       0x52, 0x49, 0x46, 0x46, 0x24, 0x40, 0x06, 0x00, 0x57, 0x41, 0x56, 0x45,
       0x66, 0x6d, 0x74, 0x20, 0x10, 0x00, 0x00, 0x00, 0x01, 0x00, 0x19, 0x00,
       0x80, 0xbb, 0x00, 0x00, 0x00, 0x9f, 0x24, 0x00, 0x32, 0x00, 0x10, 0x00,
@@ -34154,6 +34154,7 @@ std::vector<unsigned char> BinauralFilters4OAReverberantR() {
       0xff, 0xff, 0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0x00, 0x00, 0xff, 0xff,
       0x00, 0x00, 0x00, 0x00, 0xff, 0xff, 0x00, 0x00, 0xff, 0xff, 0xff, 0xff,
   };
+  return kDataArray;
 }
 // clang-format on
 
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_reverberant_r.h b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_reverberant_r.h
index 197b07d..c9c723d 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_reverberant_r.h
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_4_oa_reverberant_r.h
@@ -9,12 +9,12 @@
 #ifndef BINAURAL_FILTERS_4_OA_REVERBERANT_R_H_
 #define BINAURAL_FILTERS_4_OA_REVERBERANT_R_H_
 
-#include <vector>
+#include <span>
 
 namespace obr {
 namespace filter_files {
 
-std::vector<unsigned char> BinauralFilters4OAReverberantR();
+std::span<const unsigned char> BinauralFilters4OAReverberantR();
 
 }  // namespace filter_files
 }  // namespace obr
diff --git a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_wrapper.cc b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_wrapper.cc
index 2cca265..05a26e1 100644
--- a/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_wrapper.cc
+++ b/obr/ambisonic_binaural_decoder/binaural_filters/binaural_filters_wrapper.cc
@@ -49,7 +49,7 @@ std::unique_ptr<std::string> BinauralFiltersWrapper::GetFile(
     const std::string& filename) const {
   using AssetMap =
       std::unordered_map<std::string,
-                         std::function<std::vector<unsigned char>()>>;
+                         std::function<std::span<const unsigned char>()>>;
   static const AssetMap kAssetMap = [] {
     return AssetMap{
         {"1OAAmbientL", filter_files::BinauralFilters1OAAmbientL},
diff --git a/obr/renderer/obr_impl.cc b/obr/renderer/obr_impl.cc
index af00689..c4ebeb8 100644
--- a/obr/renderer/obr_impl.cc
+++ b/obr/renderer/obr_impl.cc
@@ -70,7 +70,7 @@ absl::Status ObrImpl::ResetDsp() {
   LOG(INFO) << "Resetting DSP.";
 
   // Enable the lock.
-  absl::MutexLock lock(mutex_);
+  absl::MutexLock lock(&mutex_);
 
   // Release resources.
   ambisonic_binaural_decoder_.reset();
@@ -116,7 +116,7 @@ absl::Status ObrImpl::InitializeDsp() {
   RETURN_IF_NOT_OK(ResetDsp());
 
   // Enable the lock.
-  absl::MutexLock lock(mutex_);
+  absl::MutexLock lock(&mutex_);
 
   // Setup Ambisonic mix bed.
   ambisonic_mix_bed_ =
@@ -187,7 +187,7 @@ void ObrImpl::Process(const AudioBuffer& input_buffer,
   CHECK_EQ(output_buffer->num_frames(), buffer_size_per_channel_);
 
   // Enable the lock.
-  absl::MutexLock lock(mutex_);
+  absl::MutexLock lock(&mutex_);
 
   // Pass audio through Ambisonic Encoder and render to Ambisonic
   // mix bed.