Great idea Canucklad, I forgot about the old timers you have mentioned. One that I specifically recall was a Pan Am 747,100 freighter that used to leave LHR every Sunday around 4pm in the mid to late eighties. To see that thing belching black smoke, struggling in to the sky making a noise like a thunderstorm used to frighten the life out of me. Not sure why, still to this day I have the perception that Pratt and Whitney engines are the noisiest of beasts.
I recall the introduction of the 737 (I think it was the 400) with the oddly shaped engine cowlings and how quiet they were.