diff --git a/backend/transcode.py b/backend/transcode.py
index 6ecf201..79a5668 100644
--- a/backend/transcode.py
+++ b/backend/transcode.py
@@ -64,13 +64,16 @@ ALL_VARIANTS = [
 
 
 def variants_for_source(src_height: int) -> List[Tuple[int, str, str, str, str]]:
-    """Pick variants ≤ source height. Always include at least one (smallest)."""
+    """Pick up to 2 variants ≤ source height (the two highest applicable renditions —
+    ALL_VARIANTS is ordered highest-to-lowest, so slicing keeps the best pair). Capped at 2
+    instead of the full ladder to roughly halve ABR encode time on this host's aging CPU, while
+    still giving a real high/low adaptive-bitrate pair for most connections."""
     if src_height <= 0:
         return [ALL_VARIANTS[2]]  # safe default 480p
     chosen = [v for v in ALL_VARIANTS if v[0] <= src_height]
     if not chosen:
         chosen = [ALL_VARIANTS[-1]]
-    return chosen
+    return chosen[:2]
 
 
 async def transcode_audio_fix(source: Path, out_dir: Path, on_status: Callable[..., Awaitable]) -> None:
@@ -133,7 +136,7 @@ async def transcode_abr(source: Path, out_dir: Path, on_status: Callable[..., Aw
     filter_complex = ";".join(fc_parts)
 
     # Per-variant thread count, not the full cap each — x264 threads are set per encoder
-    # instance, so giving every one of the (up to 4) variants the full TRANSCODE_THREADS
+    # instance, so giving every one of the (up to 2) variants the full TRANSCODE_THREADS
     # budget lets them all run near-full-tilt simultaneously and still saturate the host.
     per_variant_threads = max(1, TRANSCODE_THREADS // n)
 
@@ -143,7 +146,7 @@ async def transcode_abr(source: Path, out_dir: Path, on_status: Callable[..., Aw
         cmd += [
             "-map", f"[v{i}out]",
             f"-c:v:{i}", "libx264",
-            f"-preset:v:{i}", "veryfast",
+            f"-preset:v:{i}", "superfast",
             f"-threads:v:{i}", str(per_variant_threads),
             f"-profile:v:{i}", "main",
             f"-pix_fmt:v:{i}", "yuv420p",