Command-Line FLAC Conversion with SoX

brew install sox

cd /Downloads/your-flac-album

# macOS zsh — run inside the folder with your FLACs
base="$(basename "$PWD")"
if [[ "$base" == *"24-bit FLAC"* ]]; then
  outdir="${base/24-bit FLAC/16-bit FLAC}"
else
  outdir="${base} 16-bit FLAC"
fi
mkdir -p "$outdir"

for f in *.[Ff][Ll][Aa][Cc]; do
  sr=$(soxi -r "$f")
  bd=$(soxi -b "$f")

  # Already 16-bit? Just copy it — nothing to do.
  if [[ "$bd" == "16" ]]; then
    echo "Copying (already 16-bit @ $sr Hz): $f"
    cp "$f" "$outdir/$f"
    continue
  fi

  case "$sr" in
    44100|48000)
      echo "Converting: $f ($bd-bit @ $sr Hz → 16-bit)"
      sox -S "$f" -R -G -b 16 "$outdir/$f" dither
      ;;
    88200|176400)
      echo "Converting + resampling: $f ($bd-bit @ $sr Hz → 16-bit @ 44.1k)"
      sox -S "$f" -R -G -b 16 "$outdir/$f" rate -v -L 44100 dither
      ;;
    96000|192000)
      echo "Converting + resampling: $f ($bd-bit @ $sr Hz → 16-bit @ 48k)"
      sox -S "$f" -R -G -b 16 "$outdir/$f" rate -v -L 48000 dither
      ;;
    *)
      echo "⚠️  Unknown sample rate ($sr Hz), copying as-is: $f"
      cp "$f" "$outdir/$f"
      ;;
  esac
done

# Copy cover art and any other tracker-relevant files
for ext in png PNG jpg JPG jpeg JPEG gif GIF txt cue log nfo m3u; do
  for f in *.$ext(N); do
    cp "$f" "$outdir/$f" && echo "Copied: $f"
  done
done

echo ""
echo "✅ Done. Output folder:"
ls "$outdir" | wc -l | xargs echo "   File count:"
echo "   Path: $outdir"