Never heard what an S-3 sounds like before. Man, that is unique.
They made a really unique sound, each engine made a low "whoop" sounds every time it spooled up from idle (about 9 seconds in):
and it always seemed to come out sounding whoop-whoop, since it's practically impossible to synch those two engines perfectly. For decades this beautiful noise graced the Q at North Island, which was often under the pattern, Cecil field, and of course the bird farm/big gray floating prison.
It's a weird acoustic thing going on in the fan ducts. The only other airplane I've heard make the same sound is the Airbus A220/Bombardier C-series, when they're in front of you at the hold short line and they pull forward and when they're line up and wait and they get their takeoff clearance. Variations of the TF34/CF34 (S-3's engines) are on the A-10, pretty much every regional jet in the U.S. market, and several business jets, but none of them seem to make the sound, it's something peculiar to the installation on the S-3.
The S-3 engines also made the usual symphony of turbofan sounds—the roar from the core exhaust, the buzzsaw of the fan blades, the shriek of the compressor blades—but the whooping sound was something that took that symphony from good to great, like the tympani drums in Strauss' "Sunrise" (
2001 theme).