PF - that's pretty spectacular.
I doubt however that its related to flap vs no flap.
FTDK
I agree, the poster in the forum where I encountered the URL seemed to be blaming the pilot for not using flaps. I've never flown a Bonanza so I have no idea if flaps for take of is normal or not. It's a shame the sound dies out just after lift off, could be interesting to hear the engine.