diff --git a/ffx.sh b/ffx.sh
new file mode 100644
index 0000000..25d8418
--- /dev/null
+++ b/ffx.sh
@@ -0,0 +1,748 @@
+#!/usr/bin/env bash
+set -u
+
+P=${0##*/}
+V=1.2.0
+CFG=${FFX_CONFIG_FILE:-"$HOME/.config/ffx/helpers.sh"}
+OS=unix
+case "$(uname -s 2>/dev/null || printf unknown)" in
+  MINGW*|MSYS*|CYGWIN*) OS=windows ;;
+esac
+
+case "${NO_COLOR:-}" in
+  1|true|yes) R= G= Y= B= D= Z= ;;
+  *)
+    if [ -t 1 ]; then
+      R=$(printf '\033[31m')
+      G=$(printf '\033[32m')
+      Y=$(printf '\033[33m')
+      B=$(printf '\033[34m')
+      D=$(printf '\033[1m')
+      Z=$(printf '\033[0m')
+    else
+      R= G= Y= B= D= Z=
+    fi
+    ;;
+esac
+
+i(){ printf '%s%s→%s %s\n' "$B" "$D" "$Z" "$*"; }
+o(){ printf '%s%s✓%s %s\n' "$G" "$D" "$Z" "$*"; }
+w(){ printf '%s%s!%s %s\n' "$Y" "$D" "$Z" "$*" >&2; }
+e(){ printf '%s%s✗%s %s\n' "$R" "$D" "$Z" "$*" >&2; }
+x(){ e "$*"; exit 1; }
+h(){ command -v "$1" >/dev/null 2>&1; }
+n(){ printf '%s' "$1" | grep -Eq '^[+-]?([0-9]+([.][0-9]*)?|[.][0-9]+)$'; }
+
+usage(){
+cat <<EOF
+$P $V
+
+Usage:
+  $P <command> [arguments]
+  $P --add-helper-cmd
+  $P --remove-helper-cmd
+  $P -h|--help
+  $P <command> -h|--help
+
+Commands:
+  bass INPUT PERCENT [FINE_DB] [OUTPUT]
+  treble INPUT PERCENT [FINE_DB] [OUTPUT]
+  volume INPUT DB [OUTPUT]
+  distort INPUT [DRIVE_0_TO_10] [OUTPUT]
+  trim INPUT START_SECONDS [END_SECONDS] [OUTPUT]
+  tempo INPUT SPEED_0.125_TO_8 [OUTPUT]
+  pitch INPUT SEMITONES_-36_TO_36 [OUTPUT]
+  install
+  help
+
+Options:
+  --add-helper-cmd       Install short shell helper commands.
+  --remove-helper-cmd    Remove installed helper commands.
+  --no-color             Disable colored output.
+  -h, --help             Show help.
+  -V, --version          Show version.
+
+Examples:
+  $P bass song.mp3 25 1 bass.mp3
+  $P tempo song.mp3 1.5 fast.mp3
+  $P trim song.wav 10 30 clip.wav
+EOF
+}
+
+chelp(){
+case "$1" in
+bass|treble)
+cat <<EOF
+Usage:
+  $P $1 INPUT PERCENT [FINE_DB] [OUTPUT]
+
+PERCENT range: -200..200
+FINE_DB range: -60..60
+33 percent = 16.5 dB
+66 percent = 33 dB
+100 percent = 50 dB
+EOF
+;;
+volume)
+cat <<EOF
+Usage:
+  $P volume INPUT DB [OUTPUT]
+
+DB range: -120..120
+EOF
+;;
+distort)
+cat <<EOF
+Usage:
+  $P distort INPUT [DRIVE_0_TO_10] [OUTPUT]
+
+DRIVE range: 0..10
+EOF
+;;
+trim)
+cat <<EOF
+Usage:
+  $P trim INPUT START_SECONDS [END_SECONDS] [OUTPUT]
+EOF
+;;
+tempo)
+cat <<EOF
+Usage:
+  $P tempo INPUT SPEED_0.125_TO_8 [OUTPUT]
+
+Changes speed while preserving pitch.
+EOF
+;;
+pitch)
+cat <<EOF
+Usage:
+  $P pitch INPUT SEMITONES_-36_TO_36 [OUTPUT]
+
+Changes pitch while preserving duration.
+EOF
+;;
+*)
+usage
+;;
+esac
+}
+
+home(){
+case "$1" in
+  "~/"*) printf '%s/%s\n' "$HOME" "${1#~/}" ;;
+  *) printf '%s\n' "$1" ;;
+esac
+}
+
+dir(){
+case "$1" in
+  */*) printf '%s\n' "${1%/*}" ;;
+  *\\*) printf '%s\n' "${1%\\*}" ;;
+  *) printf '.\n' ;;
+esac
+}
+
+base(){ printf '%s\n' "${1##*[\\/]}" ;}
+
+stem(){
+local a
+a=$(base "$1")
+case "$a" in
+  *.*) printf '%s\n' "${a%.*}" ;;
+  *) printf '%s\n' "$a" ;;
+esac
+}
+
+ext(){
+local a
+a=$(base "$1")
+case "$a" in
+  *.*) printf '%s\n' "${a##*.}" ;;
+  *) printf '\n' ;;
+esac
+}
+
+rid(){
+if [ -r /dev/urandom ] && h od; then
+  od -An -N5 -tx1 /dev/urandom 2>/dev/null | tr -d ' \n'
+else
+  printf '%s%s%s' "$$" "${RANDOM:-0}" "$(date +%s)"
+fi
+}
+
+out(){
+local a=$1 t=$2 d s e
+d=$(dir "$a")
+s=$(stem "$a")
+e=$(ext "$a")
+[ -n "$e" ] || e=wav
+printf '%s/%s_%s_%s.%s\n' "$d" "$s" "$t" "$(rid)" "$e"
+}
+
+abs(){
+if h realpath; then
+  realpath -m -- "$1" 2>/dev/null
+else
+  local d b
+  d=$(dir "$1")
+  b=$(base "$1")
+  (
+    cd -P -- "$d" 2>/dev/null &&
+    printf '%s/%s\n' "$(pwd)" "$b"
+  )
+fi
+}
+
+same(){
+[ "$(abs "$1")" = "$(abs "$2")" ]
+}
+
+probe(){
+h ffprobe || return 0
+ffprobe -v error \
+  -select_streams a:0 \
+  -show_entries stream=codec_type \
+  -of default=noprint_wrappers=1:nokey=1 \
+  -- "$1" 2>/dev/null | grep -qx audio
+}
+
+pm(){
+if [ "$OS" = windows ]; then
+  h winget && { printf '%s' winget; return; }
+  h choco && { printf '%s' choco; return; }
+  h scoop && { printf '%s' scoop; return; }
+fi
+
+for a in apt-get dnf pacman zypper apk; do
+  h "$a" && { printf '%s' "$a"; return; }
+done
+}
+
+install(){
+h ffmpeg && {
+  o "ffmpeg is already installed."
+  return
+}
+
+local m
+m=$(pm)
+
+[ -n "$m" ] ||
+x "No supported package manager found. Install ffmpeg manually."
+
+i "Installing ffmpeg."
+
+case "$m" in
+  apt-get)
+    sudo apt-get update &&
+    sudo apt-get install -y ffmpeg
+    ;;
+  dnf)
+    sudo dnf install -y ffmpeg
+    ;;
+  pacman)
+    sudo pacman -Sy --noconfirm ffmpeg
+    ;;
+  zypper)
+    sudo zypper --non-interactive install ffmpeg
+    ;;
+  apk)
+    sudo apk add ffmpeg
+    ;;
+  winget)
+    winget install --id Gyan.FFmpeg -e
+    ;;
+  choco)
+    choco install ffmpeg -y
+    ;;
+  scoop)
+    scoop install ffmpeg
+    ;;
+esac || x "ffmpeg installation failed."
+
+h ffmpeg || x "ffmpeg is still unavailable."
+}
+
+req(){
+h awk || x "awk is required."
+h ffmpeg && return
+
+if [ -t 0 ]; then
+  printf 'ffmpeg is missing. Install now? [Y/n] '
+  read -r a
+  case "${a:-Y}" in
+    y|Y|yes|YES) install ;;
+    *) exit 1 ;;
+  esac
+else
+  x "ffmpeg is missing. Run: $P install"
+fi
+}
+
+prep(){
+local a=$1 d
+d=$(dir "$a")
+
+[ -d "$d" ] ||
+mkdir -p -- "$d" ||
+x "Cannot create directory: $d"
+
+[ -w "$d" ] ||
+x "Directory is not writable: $d"
+
+[ -e "$a" ] || return
+
+if [ -t 0 ]; then
+  printf '%sOutput exists: %s. Overwrite? [y/N] %s' \
+    "$Y" "$a" "$Z" >&2
+  read -r q
+  case "$q" in
+    y|Y|yes|YES) ;;
+    *) x "Output was not overwritten." ;;
+  esac
+else
+  x "Output exists; refusing overwrite: $a"
+fi
+}
+
+run(){
+local in=$1 f=$2 op=$3 d s e tmp log rc
+local -a c
+
+req
+
+in=$(home "$in")
+op=$(home "$op")
+
+[ -f "$in" ] &&
+[ -r "$in" ] ||
+x "Input is missing or unreadable: $in"
+
+[ -n "$f" ] ||
+x "Missing audio filter."
+
+same "$in" "$op" &&
+x "Input and output must differ."
+
+probe "$in" ||
+x "No readable audio stream found: $in"
+
+d=$(dir "$op")
+s=$(stem "$op")
+e=$(ext "$op")
+
+[ -n "$e" ] ||
+x "Output requires an extension."
+
+case "$(printf '%s' "$e" | tr '[:upper:]' '[:lower:]')" in
+  mp3) c=(-c:a libmp3lame -q:a 2) ;;
+  wav) c=(-c:a pcm_s16le) ;;
+  flac) c=(-c:a flac) ;;
+  ogg) c=(-c:a libvorbis -q:a 6) ;;
+  opus) c=(-c:a libopus -b:a 192k) ;;
+  m4a) c=(-c:a aac -b:a 256k -movflags +faststart) ;;
+  aac) c=(-c:a aac -b:a 256k) ;;
+  mka) c=(-c:a flac) ;;
+  *) x "Unsupported output extension: .$e" ;;
+esac
+
+prep "$op"
+
+tmp="$d/.${s}.ffx-partial.$$.$(rid).$e"
+log="$tmp.log"
+
+i "Processing: $(base "$in")"
+i "Output: $op"
+
+rm -f -- "$tmp" "$log"
+
+ffmpeg \
+  -hide_banner \
+  -nostdin \
+  -y \
+  -v warning \
+  -i "$in" \
+  -map 0:a:0 \
+  -vn \
+  -af "$f" \
+  "${c[@]}" \
+  "$tmp" 2>"$log"
+
+rc=$?
+
+if [ "$rc" -eq 0 ] && [ -s "$tmp" ]; then
+  mv -f -- "$tmp" "$op" ||
+  x "Could not finalize output."
+  rm -f -- "$log"
+  o "Done: $op"
+  return
+fi
+
+[ -s "$log" ] && cat "$log" >&2
+rm -f -- "$tmp" "$log"
+x "Processing failed."
+}
+
+db(){
+n "$1" &&
+n "${2:-0}" ||
+return 1
+
+awk -v p="$1" -v f="${2:-0}" '
+BEGIN {
+  if (p < -200 || p > 200 || f < -60 || f > 60) exit 1
+  printf "%.2f", p * .5 + f
+}'
+}
+
+tempo_filter(){
+local r=$1 z c=
+n "$r" || return 1
+
+awk -v n="$r" \
+'BEGIN { exit !(n >= .125 && n <= 8) }' ||
+return 1
+
+z=$r
+
+while awk -v n="$z" 'BEGIN { exit !(n > 2) }'; do
+  c="${c}${c:+,}atempo=2"
+  z=$(awk -v n="$z" 'BEGIN { printf "%.12f", n / 2 }')
+done
+
+while awk -v n="$z" 'BEGIN { exit !(n < .5) }'; do
+  c="${c}${c:+,}atempo=0.5"
+  z=$(awk -v n="$z" 'BEGIN { printf "%.12f", n * 2 }')
+done
+
+printf '%s%satempo=%s\n' "$c" "${c:+,}" "$z"
+}
+
+boost(){
+local t=$1 in p f=0 op g
+shift
+
+[ "$#" -ge 2 ] ||
+x "Usage: $P $t INPUT PERCENT [FINE_DB] [OUTPUT]"
+
+in=$1
+p=$2
+
+if [ "$#" -ge 3 ]; then
+  if n "$3"; then
+    f=$3
+    op=${4:-}
+  else
+    op=$3
+  fi
+fi
+
+g=$(db "$p" "$f") ||
+x "PERCENT must be -200..200; FINE_DB must be -60..60."
+
+run "$in" \
+  "$t=g=$g:f=$([ "$t" = bass ] && printf 110 || printf 4000):w=$([ "$t" = bass ] && printf .6 || printf .5)" \
+  "${op:-$(out "$in" "$t")}"
+}
+
+volume(){
+local in=${1:-} d=${2:-} op=${3:-}
+
+[ -n "$in" ] &&
+[ -n "$d" ] ||
+x "Usage: $P volume INPUT DB [OUTPUT]"
+
+n "$d" &&
+awk -v n="$d" \
+'BEGIN { exit !(n >= -120 && n <= 120) }' ||
+x "DB must be between -120 and 120."
+
+run "$in" "volume=${d}dB" \
+"${op:-$(out "$in" volume)}"
+}
+
+distort(){
+local in=${1:-} d=3 op=pg
+
+[ -n "$in" ] ||
+x "Usage: $P distort INPUT [DRIVE_0_TO_10] [OUTPUT]"
+
+if [ "$#" -ge 2 ]; then
+  if n "$2"; then
+    d=$2
+    op=${3:-}
+  else
+    op=$2
+  fi
+fi
+
+n "$d" &&
+awk -v n="$d" \
+'BEGIN { exit !(n >= 0 && n <= 10) }' ||
+x "DRIVE must be between 0 and 10."
+
+pg=$(awk -v d="$d" \
+'BEGIN { printf "%.3f", 1 + d * .85 }')
+
+run "$in" \
+"volume=$pg,alimiter=limit=.82:attack=5:release=50:level=disabled" \
+"${op:-$(out "$in" distort)}"
+}
+
+trim(){
+local in=${1:-} a=${2:-} b= op f
+
+[ -n "$in" ] &&
+[ -n "$a" ] ||
+x "Usage: $P trim INPUT START_SECONDS [END_SECONDS] [OUTPUT]"
+
+n "$a" &&
+awk -v n="$a" \
+'BEGIN { exit !(n >= 0) }' ||
+x "START_SECONDS must be zero or greater."
+
+if [ "$#" -ge 3 ]; then
+  if n "$3"; then
+    b=$3
+    op=${4:-}
+  else
+    op=$3
+  fi
+fi
+
+if [ -n "$b" ]; then
+  awk -v a="$a" -v b="$b" \
+  'BEGIN { exit !(b > a) }' ||
+  x "END_SECONDS must be greater than START_SECONDS."
+  f="atrim=start=$a:end=$b,asetpts=PTS-STARTPTS"
+else
+  f="atrim=start=$a,asetpts=PTS-STARTPTS"
+fi
+
+run "$in" "$f" "${op:-$(out "$in" trim)}"
+}
+
+speed(){
+local in=${1:-} v=${2:-} op=${3:-} f
+
+[ -n "$in" ] &&
+[ -n "$v" ] ||
+x "Usage: $P tempo INPUT SPEED_0.125_TO_8 [OUTPUT]"
+
+f=$(tempo_filter "$v") ||
+x "SPEED must be between 0.125 and 8."
+
+run "$in" "$f" "${op:-$(out "$in" tempo)}"
+}
+
+pitch(){
+local in=${1:-} s=${2:-} op=${3:-} r q f
+
+[ -n "$in" ] &&
+[ -n "$s" ] ||
+x "Usage: $P pitch INPUT SEMITONES_-36_TO_36 [OUTPUT]"
+
+n "$s" &&
+awk -v n="$s" \
+'BEGIN { exit !(n >= -36 && n <= 36) }' ||
+x "SEMITONES must be between -36 and 36."
+
+r=$(awk -v s="$s" \
+'BEGIN { printf "%.12f", 2 ^ (s / 12) }')
+
+q=$(awk -v r="$r" \
+'BEGIN { printf "%.12f", 1 / r }')
+
+f=$(tempo_filter "$q") ||
+x "Cannot safely compensate duration."
+
+run "$in" \
+"asetrate=44100*$r,aresample=44100,$f" \
+"${op:-$(out "$in" pitch)}"
+}
+
+block(){
+cat <<EOF
+# ffx helper commands
+ffbass(){ $P bass "\$@"; }
+fftreble(){ $P treble "\$@"; }
+ffvolume(){ $P volume "\$@"; }
+ffdistort(){ $P distort "\$@"; }
+fftrim(){ $P trim "\$@"; }
+fftempo(){ $P tempo "\$@"; }
+ffpitch(){ $P pitch "\$@"; }
+EOF
+}
+
+shell_rc(){
+case "${SHELL##*/}" in
+  zsh) printf '%s/.zshrc\n' "$HOME" ;;
+  bash) printf '%s/.bashrc\n' "$HOME" ;;
+  *) printf '%s/.profile\n' "$HOME" ;;
+esac
+}
+
+add(){
+local rc="$1" b
+mkdir -p -- "$(dirname "$CFG")" ||
+x "Cannot create configuration directory."
+
+if [ -f "$CFG" ] &&
+grep -Fqx 'ffbass(){' "$CFG" 2>/dev/null; then
+  o "Helper commands are already installed: $CFG"
+else
+  b=$(block)
+  {
+    [ -f "$CFG" ] && cat "$CFG"
+    printf '\n%s\n' "$b"
+  } > "$CFG.$$" ||
+  x "Cannot write helper configuration."
+
+  mv -f -- "$CFG.$$" "$CFG" ||
+  x "Cannot install helper configuration."
+fi
+
+if [ ! -f "$rc" ] ||
+! grep -Fq "$CFG" "$rc" 2>/dev/null; then
+  printf '\n[ -f "%s" ] && . "%s"\n' "$CFG" "$CFG" >> "$rc" ||
+  x "Cannot update $rc."
+fi
+
+o "Installed helper commands."
+i "Open a new terminal or run: . \"$rc\""
+}
+
+remove(){
+[ -f "$CFG" ] ||
+x "Helper configuration does not exist: $CFG"
+
+awk '
+BEGIN { skip = 0 }
+/^# ffx helper commands$/ { skip = 1; next }
+skip && /^ffpitch\(\)\{/ { skip = 0; next }
+!skip { print }
+' "$CFG" > "$CFG.$$" ||
+x "Cannot update helper configuration."
+
+mv -f -- "$CFG.$$" "$CFG" ||
+x "Cannot remove helper commands."
+
+o "Removed helper commands from $CFG."
+}
+
+main(){
+case "${1:-}" in
+  -h|--help|help)
+    if [ "$#" -gt 1 ]; then
+      chelp "$2"
+    else
+      usage
+    fi
+    ;;
+
+  -V|--version)
+    printf '%s %s\n' "$P" "$V"
+    ;;
+
+  --no-color)
+    NO_COLOR=1
+    R= G= Y= B= D= Z=
+    shift
+    main "$@"
+    ;;
+
+  --add-helper-cmd)
+    add "$(shell_rc)"
+    ;;
+
+  --remove-helper-cmd)
+    remove
+    ;;
+
+  install)
+    install
+    ;;
+
+  bass)
+    shift
+    if [ "${1:-}" = "-h" ] ||
+       [ "${1:-}" = "--help" ]; then
+      chelp bass
+    else
+      boost bass "$@"
+    fi
+    ;;
+
+  treble)
+    shift
+    if [ "${1:-}" = "-h" ] ||
+       [ "${1:-}" = "--help" ]; then
+      chelp treble
+    else
+      boost treble "$@"
+    fi
+    ;;
+
+  volume)
+    shift
+    if [ "${1:-}" = "-h" ] ||
+       [ "${1:-}" = "--help" ]; then
+      chelp volume
+    else
+      volume "$@"
+    fi
+    ;;
+
+  distort)
+    shift
+    if [ "${1:-}" = "-h" ] ||
+       [ "${1:-}" = "--help" ]; then
+      chelp distort
+    else
+      distort "$@"
+    fi
+    ;;
+
+  trim)
+    shift
+    if [ "${1:-}" = "-h" ] ||
+       [ "${1:-}" = "--help" ]; then
+      chelp trim
+    else
+      trim "$@"
+    fi
+    ;;
+
+  tempo)
+    shift
+    if [ "${1:-}" = "-h" ] ||
+       [ "${1:-}" = "--help" ]; then
+      chelp tempo
+    else
+      speed "$@"
+    fi
+    ;;
+
+  pitch)
+    shift
+    if [ "${1:-}" = "-h" ] ||
+       [ "${1:-}" = "--help" ]; then
+      chelp pitch
+    else
+      pitch "$@"
+    fi
+    ;;
+
+  "")
+    usage
+    ;;
+
+  *)
+    e "Unknown command: $1"
+    usage
+    exit 2
+    ;;
+esac
+}
+
+main "$@"
\ No newline at end of file