I suggest the question should be what amplifiers are capable of driving loads of 0.5 ohms, not what speakers are able to (huh?) go down to 0.5 ohms. By the way, AFAIK Sound Labs don't go that low, more like in the ballpark of 2 ohms or perhaps a bit lower in the high treble, where there is little energy anyway. But it's true that Apogee Scintillas go that low, and as Avguygeorge mentions, Martin Logan CLS I's dip to 1 ohm or less. There haven't been many amps able to drive Scintillas well, although a small handful are capable of driving a dead short and handle them just fine.
That reminds me of a story a friend was telling me recently about the infamous John Iverson who used to carry his little Eagle 2 amp around to dealers and tell 'em how it could drive a dead short - and as part of his impressive demonstration he'd prove it by disconnecting the speaker cables from the speakers and shorting them together while music was playing through them - and the darned amp would weld the speaker cable spades together! Utterly scary yet based upon what I've heard about Iverson, I have little reason to doubt it's true. I knew a fellow quite a few years ago who owned an Eagle 7a amp (the big one), and it was a sweet sounding brute!
Brian Walsh
That reminds me of a story a friend was telling me recently about the infamous John Iverson who used to carry his little Eagle 2 amp around to dealers and tell 'em how it could drive a dead short - and as part of his impressive demonstration he'd prove it by disconnecting the speaker cables from the speakers and shorting them together while music was playing through them - and the darned amp would weld the speaker cable spades together! Utterly scary yet based upon what I've heard about Iverson, I have little reason to doubt it's true. I knew a fellow quite a few years ago who owned an Eagle 7a amp (the big one), and it was a sweet sounding brute!
Brian Walsh