Anyone Familiar With These Infinity QLS 1s?

I am familiar with the speakers and used to own the Quantum 3's back in the day.

From my perspective they are cool speakers and if you could get them for a reasonable price they might be worth playing around with... However, for the guy's starting bid of $2500, you could do way better. In fact, I'm sure you could find a nice pair of used RS-1B's for less than that and they are considerably better speakers. For that matter Kappa 9's would also be a better and less expensive choice.

Indeed, for $2500 there are lots of better speakers than those... So unless you have some sentimental attachment (like you lost your virginity while listening to a pair), I would pass on those and keep looking. Personally, I'd only go $700 to $1000 tops on that model.

I just took a look at the listing and I think I know why he wants $2500... I have NEVER seen a pair in this just about perfect condition.. they look very good and drivers incl. watkins woofer look perfect, from what I can see..I've seen a few of these and they are always beat to hell or have replacement woofers...
Some considerations: Yes they will go very deep due to dual coils on woof's, but these really need TONS of power to get em moving.. think 500 watts a side for starters.. and high current.
Also these use the marginally good phillips 4" mid cone used in many designs (DQ-10) and I am suspicious how good these work or how they can keep up with the rest of the array, working from 200-600 cycles seems kinda weird. wonder how they came up with that design.
I always wanted to hear them (and have them) but never had the chance...

I owned a pair of the QLS.The woofers don't keep pace with the tweeters and need Power.I was more satisfied with the Acoustat 3s,more coherent.Driver replacement will be a problem,should it occur.As mentioned,the RS-1s will yield better results and in a similiar price range.