Infinity Quantum 2 - High Impedance Readings

I don't think they do. Simply a coil of coated wire, and about the only thing that can happen is overheating to the point where the varnish carbonizes, causing leakage between turns.

Most likely the inductance hasn't changed, it's just the meter or the method of measurement.

Are they the same in both speakers?
 
They were different from each other and different than the values they had written on them, some by as much as 30%! I measured with an LCR meter, set at 120hz for the coils on the woofer circuit.
 
Hmm. Have you checked DC resistance of each of the inductors? With at least one leg detached. If pairs are significantly different, they could have shorted turns.

I really have no experience with measuring inductors at a specific frequency vs. other frequencies but it seems like pairs should at least match up when measured on the same meter at the same frequency. If they are in good shape.
 
10 days later I am happy to report that my QLS-1 project is complete! After a quick listen, I am very happy with the results! I haven't tried to adjust the level settings/speaker locations yet but I am already convinced that I like the QLS's better than my Ren 90's! The bass, the imaging, the detail is all back and then some. I think the enhanced Solen replacement caps I used for the mid bass, mids and highs are helping. The original caps were rated for 100V, the new ones for the mids are rated at 400V and for the tweeters 700V. I do not remember the speakers producing such a 3D image. At higher volumes it sounds like my rear surround speakers are on but they are not! I can't believe I waited so long to do this. I had doubts the speakers could be revived. But with a little help from my new found friends magic happened. Thanks to all that chimed in with your support! Reflowing the solder on the tweeters was a big help. I needed to use 2 longer diagonal 6-32 screws to guide the tweeters back together. The tweeter wiring diagram was also helpful.

I am disappointed in the quality of the replacement pots, but they do work and I have no choice since the originals were hijacked by a repair shop and replaced with low wattage ones. I had to slot the level control holes a bit with a file to make them fit. To reattach the level control plastic plate back in the speaker I used about 10 small wood screws and I made a gasket out of a 1/8" thick butyl rubber sheet. I did not want to glue it in since I am prone to more tinkering. I also moved the cap and coil for the dome mids to the bigger wooden board to minimize clutter. I did not change the speaker terminals because the originals are keyed to keep the correct orientation for the shorting wires when not biamping. I went to 14 gauge wire for the woofer wiring and left the rest as is. I also added a 3.9 uf 400V Solen poly cap to the parallel connected caps for the woofers. The bass sounds great, how much those small caps are helping is unknown. I think I will be getting even tighter bass as those electrolytics "break in".

At first I used the QLS on the left channel and a Ren on the right channel. I needed to boast the left channel level on the QLS by 3db to match the Ren level. When comparing to the Ren 90's it is now clear to me that the midrange in the Rens is overstated and harsh in comparison. There are no level controls on the Rens, but they are keepers .

I have some things going on that will prevent me from tinkering any further for a while, but I can't wait to play some more... I included before and after photos of one of the crossovers.

Thanks, Vinny M
 
Hi Chef,

I saw your post about the coils. I spoke to Bill Watkins Jr. about the same thing and he assured me that they are fine. But now that I think about it the values that I was getting were all lower than the expected value when I measured them at 100 hz. At 30 hz the inductance I think would be even lower. I would hate to call Bill again, he will think I am crazy. But if you want to call him, he tries to be very helpful. Maybe we can get a definitive answer if we phrase the question right. In general at higher frequencies inductance should be higher not lower I think?
 
I had read something about inductor placement on the xo board as being somehow important.
I found graph showing good, bad or fair orientations.
The inductor placement on the Q2 board looked fine.
However, the QLS-1 placement not so good so I reoriented them on the board fairly easily.
I suppose it's better.

Coils.png

Picture 821.jpg
Picture 2191.jpg
 
I'm not sure what is going on with the inductors. I was strongly discouraged to change them by Bill Watkins Jr. when I told him the values I was getting were way out of spec. Anyone that can provide more clarity on the issue would be greatly appreciated. I only know what Bill said and that I am getting good bass results. If I could be doing better, I would be on board with that. From reading about measuring iron core coils, it can be tricky and dependent on current levels in circuit.
 
I would suspect your measurements rather than the inductors. I had a Chinese LCR meter that was way off on the inductors in my RS1b speakers (and it wasn’t reliable on the capacitors either). I finally took a signal generator and an oscilloscope and measured the inductors the hard way. They were spot on.
 
That resolution chart means you should let the meter auto range for inductance measurements, or use 10KHz if you are setting the frequency.
 
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Hi slimpikkins, I think I saw a post from you using Miller Sound to recone your woofers. I was doing a little listening last night and heard a wheezing sound from my right woofer during an acoustic bass solo from Stanley Clarke. I had these woofers refoamed 15 years ago at a local speaker shop in S. FL and I think they botched it. Watkins does not have any more woofers so it looks like Miller Sound is my best bet. They don't accept calls on Monday, but I was wondering if you think Miller can resolve that by reconing and how much do they charge for the pair? Thanks!
 
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