diff --git a/hosts/common/programs/mpv/default.nix b/hosts/common/programs/mpv/default.nix
index 885ab09b9..22877b413 100644
--- a/hosts/common/programs/mpv/default.nix
+++ b/hosts/common/programs/mpv/default.nix
@@ -41,7 +41,6 @@
 
 let
   cfg = config.sane.programs.mpv;
-  myHrtf = "${pkgs.sofacoustics.listen.irc_1052}/share/sofa/listen-irc_1052.sofa";
   uosc = pkgs.mpvScripts.uosc.overrideAttrs (upstream: {
     version = "5.2.0-unstable-2024-03-13";
     src = lib.warnIf (lib.versionOlder "5.2.0" upstream.version) "uosc outdated; remove patch?" pkgs.fetchFromGitHub {
@@ -138,6 +137,11 @@ let
   });
 in
 {
+  sane.programs.sofa-default = {
+    packageUnwrapped = pkgs.sofacoustics.listen.irc_1052.asDefault;
+    sandbox.enable = false;  #< data only
+  };
+
   sane.programs.mpv = {
     packageUnwrapped = pkgs.mpv-unwrapped.wrapper {
       mpv = pkgs.mpv-unwrapped.override rec {
@@ -195,6 +199,7 @@ in
       "sane-cast"
       "sane-die-with-parent"
       "xdg-terminal-exec"
+      "sofa-default"
     ];
 
     sandbox.method = "bwrap";
@@ -227,7 +232,6 @@ in
     fs.".config/mpv/scripts/sane_cast/main.lua".symlink.target = ./sane_cast/main.lua;
     fs.".config/mpv/scripts/sane_sysvol/main.lua".symlink.target = ./sane_sysvol/main.lua;
     fs.".config/mpv/scripts/sane_sysvol/non_blocking_popen.lua".symlink.target = ./sane_sysvol/non_blocking_popen.lua;
-    fs.".config/mpv/hrtf.sofa".symlink.target = myHrtf;
     fs.".config/mpv/input.conf".symlink.target = ./input.conf;
     fs.".config/mpv/mpv.conf".symlink.target = ./mpv.conf;
     fs.".config/mpv/script-opts/osc.conf".symlink.target = ./osc.conf;
@@ -257,5 +261,9 @@ in
     #v Loupe image viewer can't open URIs, so use mpv instead
     mime.urlAssociations."^https?://i\.imgur.com/.+" = "mpv.desktop";
   };
+
+  environment.pathsToLink = lib.mkIf cfg.enabled [
+    "/share/libmysofa"
+  ];
 }
 
diff --git a/hosts/common/programs/mpv/mpv.conf b/hosts/common/programs/mpv/mpv.conf
index eebb09888..2ff73873e 100644
--- a/hosts/common/programs/mpv/mpv.conf
+++ b/hosts/common/programs/mpv/mpv.conf
@@ -32,4 +32,4 @@ border=no
 # see: <https://ffmpeg.org/ffmpeg-filters.html#sofalizer>
 # TODO: this maybe belongs in pipewire instead of mpv.
 # at least, provide a way to disable the downmixing, so i can still output 5.1 over HDMI?
-af=sofalizer=sofa=/home/colin/.config/mpv/hrtf.sofa
+af=sofalizer=sofa=/etc/profiles/per-user/colin/share/libmysofa/default.sofa:gain=11
diff --git a/pkgs/additional/sofacoustics/default.nix b/pkgs/additional/sofacoustics/default.nix
index db246f8d6..d5a7d3b68 100644
--- a/pkgs/additional/sofacoustics/default.nix
+++ b/pkgs/additional/sofacoustics/default.nix
@@ -3,11 +3,12 @@
   lib,
   newScope,
   nix-update-script,
+  runCommandLocal,
   stdenvNoCC,
   symlinkJoin,
 }:
 lib.makeScope newScope (self: with self; {
-  downloadSofacoustics = prefix: database: name: hash: stdenvNoCC.mkDerivation {
+  downloadSofacoustics = prefix: database: name: hash: stdenvNoCC.mkDerivation (finalAttrs: {
     name = "${database}-${name}";
     src = fetchurl {
       url = "${prefix}${name}.sofa";
@@ -17,8 +18,8 @@ lib.makeScope newScope (self: with self; {
 
     dontUnpack = true;
     installPhase = ''
-      mkdir -p $out/share/sofa
-      cp $src $out/share/sofa/${database}-${name}.sofa
+      mkdir -p $out/share/libmysofa
+      cp $src $out/share/libmysofa/${database}-${name}.sofa
     '';
     doBuild = false;
 
@@ -27,7 +28,11 @@ lib.makeScope newScope (self: with self; {
     passthru.updateScript = nix-update-script {
       extraArgs = [ "--version" "skip" ];
     };
-  };
+    passthru.asDefault = runCommandLocal "${database}-${name}-as-default" {} ''
+      mkdir -p $out/share/libmysofa
+      ln -s "${finalAttrs.finalPackage}/share/libmysofa/${database}-${name}.sofa" $out/share/libmysofa/default.sofa
+    '';
+  });
 
   ari = lib.recurseIntoAttrs (lib.mapAttrs (downloadSofacoustics "https://sofacoustics.org/data/database/ari/hrtf%20" "ari") {
     # in-the-ear measurements from real human subjects, complete with detailed anthropometric data.