The 1970's Infinity QLS 1...How would it compare?


How would a properly driven (worth a 500 page thesis in itself!) pair of these compare to $20,000 and under mainstays of today? These speakers have become an enigma to me...They were always two or three or a hundred and fifty steps beyond my grasp for different reasons and now they're getting hard to find and harder to find parts for so as to be forever relegated to the "one that got away" files. Anyone ever own these or otherwise spend any time with them? Closest I ever got to auditioning them was prob. late '78 at a Pacific Stereo (Unfortunately someone had underpowered them with one of the 80 lb. "monster recievers" of the day only hours before I got there so all I got was a look.) Ah, youth........
lg1

Showing 1 response by cdface

I realize I'm digging up an old thread here, but I just wanted to state for the record that after a few days of work and a few hundred dollars worth of crossover rebuilding and new internal wiring, AND with these speakers being properly driven (which was clearly important to the OP and not addressed above) by a single 500Wpc Yamaha PC5002M amplifier (the pro version of the 101M), I believe you'd all find that the QLS1s are a truly fantastic speaker, certainly much better than what's been described above.

The only criticism I can still agree with is that there IS a little extra midbass, though it's not much. I haven't done a frequency response sweep to make sure my potentiometer settings are dialed in properly, so this may be the answer to that. If not, I'd bet that a judicious re-stuffing of the midbass coupler's transmission line should get rid of most of the issue. Oh, and the cabinet, though already braced, can indeed get a bit resonant with some loud bass hits below 35Hz or so. However, this is fairly simple to fix with a dowel rod and some DIY instructions, and I actually intend to do this in the next few weeks.

I guess that ultimately it depends on what exactly what you want out of a speaker, and how you rank these different wants. I would say that a rebuilt QLS1 does almost everything quite well, and some things even better than that. I have no experience with new >$2k speakers, so I can't speak to that part of the OP. Just don't expect the world out of a completely stock model, and be prepared to spend some dough on a serious amp.