科幻启动确认音

Compact sci-fi launch confirmation, 1800 ms. A deep 70 Hz ignition thump, then a rising three-note glass-and-steel chime at 520, 660 and 990 Hz with a long clean ring on the last note, and a low rumble fading underneath across the full 1800 ms. Cold, bright, earned. Dry, no reverb hall, no orchestra, no choir.