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Any Infinity QLS owners here?

The domes are very difficult to locate, I saw a matched pair sell on eBay for $175 several months ago, and most all speaker repair places won't even touch them. Fortunately, through frustration and a strong desire not to be defeated by a broken tinsel, I figured out a way to affect a repair that works for me, though isn't particularly pretty. The EMITs can be fixed using a rear window defrost repair kit, or so I've heard. Fortunately, mine were the only things working on my Q2s when I got them. The midbass coupler shows up a bit more often than either of those, having been used in several Quantum models. I believe there's a pair on that auction site right now, though a bit rusted. The 5 ohm pots in the crossovers are horribly prone to going bad, which is the last thing mine need to have fixed (I'm still looking for a suitable substitute.) With enough desire and drive, the Quantum models can be brought back to life.

I typed up a quick how to on the dome repair a while back that can be found here, for anyone looking for a fix.

I'm an English lit student and yes, I really shouldn't be up. It is a condition I shall endeavor to correct now.
- JP
 
The crossovers in the QLS and several of the smaller brethren were remarkable. Gigantic air core inductors because of the dual drive woofer and the very low crossover points, and elaborate, of course, because it's a four way design with an additional tweeter thrown into the mix. I heard them at a friends house for a couple of hours and they sounded quite good, but the bass wasn't what I'd been expecting. (His music choices perhaps?)

I've owned Quantum 3's and loved them, but I was too stupid to put a decent sized amp on them. All I had was a 100 wpc BGW amp which was pretty insufficient. When I finally traded them in at a store; to test them out, the salesman blasted them with a 250 wpc amp and they sounded wonderful. I should have backed out of the trade-in right then, but I felt committed. And probably should have been in retrospect.
 
Soundcraftsmen amps would do the trick, as would a Yahama M-80 or M-85. These amps are all stable into 2 ohm loads.
 
Qls

Hi Folks,
Thanks for the great information, great website. I'll post some pictures soon of the QLS's. I wasn't able to get them out of storage yesterday, I couldn't find anyone to help me carry them.... I was able to open up the outer box, they are double boxed in the original Infinity boxes. The inside box looked clean so I'm hoping the speakers are preserved well.
When I boxed them up over ten years ago, the woofers needed repair and I remember the crossover needed work, the midranges would cut out when turning the adjustment dials.
Reading this website is getting me very excited about what I'll find when I can open the boxes.
Thanks for all your help.
Jim
 
jim_arndt said:
When I boxed them up over ten years ago, the woofers needed repair and I remember the crossover needed work, the midranges would cut out when turning the adjustment dials.
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Jim,

What you've described is two of the four most common issues with these older Quantums, and the two easiest to fix. In fact, they've already been mentioned. The first was because the foam surrounds were rotting, correct? If so, you can order a repair kit from Orange County Speaker Repair, though bear in mind you'll need an exacto knife to trim the cardboard gasket segments (they're a bit too large), but that's a simple matter. The issue with the midranges is due to the 5Ω 25W potentiometers that control the levels going bad with age. I've not found a suitable substitute yet, but perhaps someone like GordonW, an AK member a pro speaker repairer, can help out on that. Your control may only need a good cleaning with DeOxit or a manual cleaning akin to the AR 3 type posted several times around here.

Now, why would you need help moving them? They're only spec'd at 190 lbs apiece. :thmbsp:

- JP
 
Dynaco 416 powering QLS's

Hi Folks,
Thanks for the input. The more I research this, I'm really getting excited about what I have. I have a Dynaco 416 with the c-100. The Dynaco needs a little work and the C-100 won't charge (bad cap?) My dad used to power the QLS's with this amp, but I thought it was always weak in the bass.

If I get serious about investing in fixing up these speakers, is the Dynaco 416 a good match for this speaker? Does the Dynaco do well with the 2 Ohm load? I was thinking of picking up a 2nd 416 on ebay, and powering the speakers in a dual amp configuration. The Infinity QLS manual recommends one amp powering the left speaker, and the other powering the right speaker (to keep the Watkins woofer from sucking the power supply dry). One channel of each amp would power the woofer, the other channel the mid and tweeters.

I've got such a rare collection of equipment left over from my dad, I wouldn't mind investing some dollars to get this equipment sounding good.

I remember my dad commenting "Mom would leave me if she knew how much money I spent on these speakers." I think I remember him saying he picked them up used for $2000, that would be around 1978.)

All this stuff has been sitting in my moms garage for 20 years. If you had this treasure chest to play with, how would you set it up?

Pair Infinity QLS's
Dynaco 416 with C-100
Dynaco stereo 70
Dynaco Mono amp (I believe 35 watt per channel, factory built)
Dynaco Mono amp (same as above, but unbuilt kit.)
Pioneer Spec-1 Pre Amp
Hafler dh-101 Pre Amp
Pioneer TX-9500 II Tuner
Phase Linear 400 (Mom smoked it)
Techniques SL-1300 turntable
Heathkit AD-1702 electronic crossover

Thanks,
Jim
 
Jim,

You might want to consider starting a new thread in one of the other forums, say General Audio, or several, such as one in the Tubes forum for your tube gear, etc so your questions can get the attention they deserve. I'm afraid I don't know too much about the gear you do have, other than it appears to be an incredible setup.

If I might make a recommendation, that unbuilt Dynaco kit could fetch big bucks on eBay, since unbuilt kits are so rare and collectors love them. If you're not too sentimentally attached to that one piece, the funds you could earn from it would pay for proper refurbishment of all the rest, I think.

Just a little note, I was reading a Stereophile review on the big Infinity Betas like Negotiableterms has (man, am I jealous of those) and read a mention that Arnie Nudell, the man behind Infinity, referred to voice his big speakers with tubes. So, it might be worth considering trying out the mids/tweeters section of those big Quantums with some of your tube gear and have the big SS gear on the Watkins.

Incredible treasure stash you have there, from what I can tell. Your father must've been quite the enthusiast. Here's to hoping you can get it all fixed up and enjoy the nostalgia.

- JP
 
Hi Folks,
I finally got the QLS's out of storage. Bad news, the woofers were removed and losts. Yes it was me, 20 years ago when I was young and dumb and owned a screwdriver. I removed them to get them repaired, had no idea where to bring them, and ultimately re-boxed them up in a separate box. Unfortunately that box cannot be found.

The speakers were well packaged in plastic and double boxed in the original Infinity boxes. So I've got a pair of Infinity QLS's in decent shape, less two woofers. What is the likely hood of finding a pair of replacement woofers?
Jim
 
jim_arndt said:
So I've got a pair of Infinity QLS's in decent shape, less two woofers. What is the likely hood of finding a pair of replacement woofers?
Jim
Click to expand...
Pretty good. Any 12" Infinity-Watkins woofer will work with your speakers and fortunately for you, essentially the same woofer was used for several series of Infinity speakers over a span of 10+ years. However, the original woofers for your Quantums had the paper cone while all the others went to poly. I'm uncertain if this will produce any detrimental effect or would actually be an upgrade. As to availability, watch eBay. A pair of Watkins tend to crop up every two or three weeks, so just be a little patient and you should be good to go.

- JP
 
Charivari said:
...However, the original woofers for your Quantums had the paper cone while all the others went to poly.
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I think only the early QLSs have paper. Mine have poly, and they're original. There are at least two production versions. In the later version, the mid-bass coupler is moved to a different spot. I think there are more variations than that, although I've no idea how to track this.

JP is right about everything else, as he usually is.
 
Yes!!!

I heard a set of those in a listenning room at Tech HI-FI when I bought my first set of Q3's in 1979, they used a large SAE amp to drive them, what a sound. I just couldn't spring for a set of those at the time. Now I'm kinda sorry I didn't :no: . BUTT! my 2 sets of Q3's are starting to sound real good now that I re-foamed one set and now drive each set with a Kenny KR-9600, they sound real good even though one is still a little crippled by a bad dome mid-range. I posted some pics of one of the sets in another thread with a set of JBL 100 Studio monitors on top of them.

:banana:
 
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Negotiableterms said:
I think only the early QLSs have paper. Mine have poly, and they're original. There are at least two production versions. In the later version, the mid-bass coupler is moved to a different spot. I think there are more variations than that, although I've no idea how to track this.

JP is right about everything else, as he usually is.
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Wha-what? I was wrong about something? I can't even remember the last time that happened. (j/k) :D

From what I've read, the poly Watkins were introduced with the Reference Series immediately following the Quantum series and were the first poly cones in the industry. Maybe your QLS were produced towards the end of the run and overlapped with the RS production. If that's the case, then being Infinities TOTL speaks, it only makes sense that they'd incorporate technological advancements into it as they figured out new things.

- JP
 
SicMan said:
Some large ones for sale, and if you search the speakers and subwoofers section there's alot more! AHHHHHHHH!!! what do I do? :scratch2:
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Buy 'em. Buy 'em All!! Muah haha. :nutz:

I saw those Kappa 9s and dreamed the good dream. A shame I can't afford a pair of those, but then again, I'm holding out for the real bigguns: QLS-1s, IRS V/Betas, QRS, and maybe allow for the Ren 90.

- JP
 
I haven't had time to wade thru this whole thread yet, but have seen mention of different Infinity drivers needing repairs. My non AK buddy Jim can fix most if not all of them very reasonably, example: any size woofer refoamed $35 a pair total plus shipping. He specializes in Infinity drivers and has been repairing these for years. As long as they haven't been driven to voice coil melt down, more than likely they can be repaired. Pm me if you need the hook up!
 
Charivari said:
...... I'm holding out for the real bigguns: QLS-1s, IRS V/Betas, QRS, and maybe allow for the Ren 90.

- JP
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Yep, those would be good! All playing at the same time :music:
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trespassing.jpg
 
Yeah, I hear ya SicMan, all those big Infinities playing at once would probably be my audio nirvana. Heck the IRS V and IRS Betas have those separate bass towers that I'd love to have with any speaker. Mmm, down 1.5 dB at 14 Hz anechoic, that's the thing dreams are made of.

On a related note, I downloaded the correction values for my Radio Shack SPL meter last night and made a disc of test tones to match the values. Today, I've been doing some measurements without the Quantum 2s particularly well positioned or anything and the results have been amazing. In my room, my Q2s (spec'd at -2 dB at 24 Hz anechoic) are only down 9 dB at 10 Hz, 4 dB at 16 Hz, and flat +/- 2 dB (aside from one - 7.5 dB room mode at ~63 Hz) from 18 Hz on up to 100 Hz. No, I did not have my subwoofer engaged at the time, so, wow, those Watkins are amazing. Just imagine the QLS-1s that are supposed to only be 2 dB down at 18 Hz anechoic. Or more incredibly what 12 of them as in the bigger IRS series must do if just 2 can do this so well.

- JP
 
Charivari said:
Yeah, I hear ya SicMan, all those big Infinities playing at once would probably be my audio nirvana. Heck the IRS V and IRS Betas have those separate bass towers that I'd love to have with any speaker. Mmm, down 1.5 dB at 14 Hz anechoic, that's the thing dreams are made of.

On a related note, I downloaded the correction values for my Radio Shack SPL meter last night and made a disc of test tones to match the values. Today, I've been doing some measurements without the Quantum 2s particularly well positioned or anything and the results have been amazing. In my room, my Q2s (spec'd at -2 dB at 24 Hz anechoic) are only down 9 dB at 10 Hz, 4 dB at 16 Hz, and flat +/- 2 dB (aside from one - 7.5 dB room mode at ~63 Hz) from 18 Hz on up to 100 Hz. No, I did not have my subwoofer engaged at the time, so, wow, those Watkins are amazing. Just imagine the QLS-1s that are supposed to only be 2 dB down at 18 Hz anechoic. Or more incredibly what 12 of them as in the bigger IRS series must do if just 2 can do this so well.

- JP
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Oh hell ya if your gonna dream, dream big :yes:

IRS Betas big bad ass, WAF :no: I'd give my... oh never mind...

No you don't have that problem (WAF) yet, Don't do it JP :nono:

Yeah right, one day some sweet little thing will turn your head and all your hard work will either be a blessing or a curse :yes: Choose wisely!

If it wasn't for you and Grumpy steering me in this direction a while ago, I would have never known just how good those Watkins woofers and ribbon tweets and mids sound :thmbsp: :thmbsp:

I think I may have to buy a meter, curiousity is killing me, damn those Watkins go low. I wonder how more clean power would change things :yes:
 
Army said:
damn those Watkins go low. I wonder how more clean power would change things
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I've done that experiment. More power will help a lot, if it's the right kind. The impedence curve on the Watkins looks like the swiss alps, so the amp has to be a true voltage source down to 2 ohms. Sadly, that means BIG BUCKS, because there are few vintage units that will do it. 200w @ 8 ohms = 800w @ 2 ohms... most amps fry themselves long before that.

To really hear what they can do, you're lookin for one of those 150 lb gorilla amps, like Threshold, or Krell, or maybe one of the big McIntosh units that has 2 ohm taps.

It's the curse of Infinity: great bass, if you can deliver the power, and a muddy mess if you can't.
 
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