Infinity QLS1 Emit Repair with Pictures.

During the recent recapping of my QLS1s I noticed several of my
Emits were not working. Since I haven't repaired these before I borrowed
AK member OMI,s Idea in post 15 of this thread http://www.audiokarma.org/forums/showthread.php?t=65571. I appreciate the advice from the regulars
here in the Infinity thread for helping me get one step closer to getting these QLS1s back to spec. I ended up repairing 4 Emits with 100% success.
The following pictures may help someone with this tricky little repair on their Emits.
These repairs only work with Diaphragms that still have good traces.

I started out by removing the 2 center screws.Sorry about the muddy pic.



Then I loosened the screws on one end until the threads were flush with the back plate.



Then I backed out the screws in the other end as evenly as possible and allowed the 2 halves to separate at one end. ( Its important that the 2 remaining screws have a good bite to hold the plates evenly.



At this point just stand the Emit on end and holding the two halves apart, remove the 2 remaining screws and separate the 2 halves. (DO NOT ALLOW THEM TO COME TOGETHER).



Remove the protective film and the Diaphragm. At this point I used some D5 on a Q tip to lightly clean those solder post. My original readings on the meter were 52.9 ohms and the cleaning alone dropped that to 14.5 ohms.
Note the corrosion on the post !




After cleaning those post I turned the Diaphragm over using very little heat
I melted the solder at the 2 post. (Note : Do this quickly, It only takes a Second to flash the joint.) I also put down some fresh Solder where the Driver wires connect. (this will help when you re-connect it later)




Put the Diaphragm and protective sheet back on the Face half with the 4 end screws in the face. and bring it close to the edge of the bench where you can start the first screws from below (Its easier than it sounds)
Place the back edge down on those 2 screws while holding the other end up and away. Go ahead and tighten one end about halfway.




Now just squeeze the other end together and put the rest of the screws in and your done.



Here is the result ! I now have 16 working Emits ! The meter readings on all 4 I worked on were between 5.5 to 5.8 ohms

Great job.
Having those pics and your description makes it very understandable.

Hi JT45,

I have a tip for the safely separation and re-assembling the front and back plate. Thus can not solve by mistake during one of the screws of the plates away abruptly to the side, so I can do it with more security.

When you first loosen the screws I guess first two diagonally opposite screws and remove them completely. Thus, the plates with the rest of the screws is still very firmly in its leadership.

Then I take two much longer screws (1-2 inches) and twist it until shortly before the end again, so that there is still some gap. Now all the other screws can savely removed. Here, nothing can happen, because the two long screws holding the plates are tight. So also the very strong magnets to stay clean in the guide.

Then turn the two long screws slowly out. We note here that the magnetic force with the bigger gap is getting weaker. So you can end up with a plate off completely safe.

During assembly, went to the same method before, but in reverse order. Thus a very safe repair of Emits is possible without damaging anything.

This method I use by all the Emits and Emims of all models. It is very savely.

Klaus

Sorry fo rmy pure english (via google translator)

Thanks dcmaster, I actually tried using longer screws and that works too, But I found it easier and much quicker to just use the original screws as long as you exercise caution
and use one end to lock it in place.