QLS recap surprise, a little help please.

chef free

Super Member
I got myself a schematic and ordered new caps for the woofer circuit. Caps arrived today so I opened up the boxes and found everything matching the schematic EXCEPT the 4.5 ohm woofer circuit has 8 200uf caps! The schematic shows 1100uf, but thats 1600uf! Both crossovers are like this. This pair has a painted front and two spacer rings which move the woofer out, is that an early or late production (#'s 7000296 and 7000297)?

Now what?
 
Another "SURPRISE!" courtesy of the fine folks on the Infinity assembly line.
If you are sure your QLS are 100% original (no prior crossover reworking) it may be best to go with 1600uf replacement cap(s).

There have been many instances of Infinity making non documented production run crossover changes.

You're not the first to find their crossovers as produced don't match the "official" schematic. Chances are you won't be the last.

It's not a bad idea when recapping vintage Infinities to VISUALLY verify what components are/were actually used before ordering.
 
8-200uf on 1 bank. 7-200uf on second, these are the early QLS , mine are 7000290-7000291 were pretty close
Al
 
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The laters have different cone, but it's your choice :) I think the magnet on the later woofer was a bit heavier. Not positive on this tho.
 
I'd stick with the values that are in there...Unless it looks like someone else modified it...
 
I got myself a schematic and ordered new caps for the woofer circuit. Caps arrived today so I opened up the boxes and found everything matching the schematic EXCEPT the 4.5 ohm woofer circuit has 8 200uf caps! The schematic shows 1100uf, but thats 1600uf! Both crossovers are like this. This pair has a painted front and two spacer rings which move the woofer out, is that an early or late production (#'s 7000296 and 7000297)?

Now what?

The black wire is usually associated with the 2 ohm voice coil and is connected inline with the largest capacitor(14/1600uf) and 20mh inductor coil.
The red, the smaller of the two(1100uf and 6.5mh).
 
Color of the wires aside, the positive lead of the 2 ohm voice coil should have the largest value components(20mh/14-1600uf) inline....

One would assume so but I opened up those speakers and there is was. The spec sheet and many photos on this very site show an 1100uf on the 4.5ohm circuit and 1400uf on the 2ohm circuit. Pictures of older QLS1's show exactly what was in my speakers.

Do you know how this change would the effect the sound of the speakers? I currently have one speaker recapped with 1100uf while the other is original. They sound very different with the recapped speaker having less upper bass. The low end is the same which is to be expected since the both have the 1400uf on the 2 ohm side of the woofer. I still can't tell which I think sounds better. The recapped one (1100uf on 4.5ohm) may sound more accurate but the one with the 1600uf on 4.5 ohm has a more "exciting" sound.

I'm wondering why did they change it.
 
Now I have discovered that the old caps are closer in value to their claimed value than the supposed 5% caps I got from Parts Express! I wish I had never taken the originals out!

I'm trying a 1100uf bundle in one speaker and a 1600uf bundle in the other. The 1100uf set up does not bottom out the woofer as easily. Maybe this is why they changed to 1100uf.
 
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