Those Mach One's look crazy!
I actually remember the Mach Two's. I'm not sure how old those are, but when I first got interested in audio, at the tender age of 14, my very first pair of "real" speakers were some Realistic bookshelf speakers from my local Radio Shack. I remember lusting after the Mach Two's because, well, they were big and looked impressive. I really had no clue what this whole world of audio was about...all I knew is that I hated the fact that my bookshelf speakers had paper cones. So, I purchased 6.5" poly replacements and stuck 'em in there. Proper cabinet size and crossovers be damned! Ahh, Realistic. Takes me back.