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Rebuild Quantum Line Source crossover

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screamingbeef

New Member
I have a pair of Quantum Line Source speakers, and one of the crossovers has gone bad, looking to repair/rebuild it. I've gotten the technical schematics of the crossover, but don't know where to source the caps etc.
Does anyone on here have any technical knowledge on this procedure?
 
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you may need/want to use several different sources. Parts-Express and Madisound are recommended.
 
You can also check with MCM Electronics, they are one of our sites sponsors (click the link below). :D

Yank
 
Thanks for that info guys :)
But I was looking for more in depth help than that, like a step by step guide or something along those lines. I've never done this before, so I need lots of help.
Do MCM or any of the others offer straight replacement crossovers? I did a quick search but didn't turn up anything useful.
 
Welcome to AK screamingbeef! This has been covered in a lot of threads, to search it, try clicking search above and type QLS1 into the "search AK with Google" box. You should find the info you need.

When you say the xover has "gone bad" can you be more specific? Often the tweeter, mid or mid-bass pots will corrode and cut out. They are very hard to find replacements for these days and usually can be brought back to life with a dismantle and cleaning with contact cleaner or Deoxit.
 
screamingbeef said:
Thanks for that info guys :)
But I was looking for more in depth help than that, like a step by step guide or something along those lines.
Click to expand...

well you didn't say that before :D

it's really just a matter of getting new parts to replace the old ones. besides the cleaned pots, the only thing i left in my pair were the woofer and midbass inductors, though if i had the money i might have replaced those too. go by the schematic for exact values on everything. with the woofer capacitors, you will probably want to parallel three or more smaller capacitors for safety and performance reasons.

the real trick is getting to understand the circuit, because you're going to have to reorganize the physical layout with the new parts since they are different sizes.
 
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jimreeves said:
Welcome to AK screamingbeef! This has been covered in a lot of threads, to search it, try clicking search above and type QLS1 into the "search AK with Google" box. You should find the info you need.

When you say the xover has "gone bad" can you be more specific? Often the tweeter, mid or mid-bass pots will corrode and cut out. They are very hard to find replacements for these days and usually can be brought back to life with a dismantle and cleaning with contact cleaner or Deoxit.
Click to expand...

On the left channel, when there's loud bass there's a loud bang/crack that sounds like I'm peaking the woofer. We've tried switching channels on the Peavey 2000 Watt Power amp but the left side continues to do it, so it's not the amp.
So we switched woofers but the left channel continues to do it. We even lowered the levels on the amp to the left channel and that helps a bit, but anything with bass, makes that noise.
We've purchased replacement Watkins woofers for both speakers, same deal.
This is what makes me think the caps have started to dry out or something along those lines. Which leads me to these excellent forums with very helpful forum members :)

I feel the need to defend myself though, I did do a search but I admit I only tried "Infinity Quantum Line Source" not the QLS1 :(

Thanks for the links, I will take a look, I can't wait to get this repaired as right now I'm using just a consumer JBL 12" sub-woofer and while it's.....boomy it doesn't have the clarity or tone of the Watkins.
 
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