First QLS-1 comes out for cleaning and serious look.

[7.62]

Tonight the first of the pair I purchased is out and in the office for cleaning,measuring and possibly recapping, reflowing the emits etc. I expect this to take a few weeks. First up will be removal of the woofer for refoaming then moving further into the speaker.

I know there's been so much information shared and I'll be using it as a baseline, but while I'm doing this if anyone wants any pictures of something specific I'll be happy to share. This should be No# 7001669 but the edges of the sticker were peeling and I pulled it back to reveal another sticker with the serial number 7001919. Kinda strange but both look like factory stickers. So for now I'm going with 7001669 & 7001670.

I'm sure I'm going to have some questions as I dig in, I respect your guys opinion. So here's no 7001669 /7001919 and some close up's of the mids and emits, they all look the same.

 

[7.62]

I measured what I could tonight, here's the breakdown.

Emit bank. 2.9 / 3.1 ohms
Midrange domes. 5.2 ohms
Midbass coupler, not original. 6.9 ohms
Rear tweeter. 6.2 ohms
Watkins Woofer. 2.1 ohms / 4.9 ohms

So I'm guessing everything driver wise is OK. If anyone thinks these numbers are bad please share your thoughts.

Thanks Much,
David.

 

[goodolpg]

Enjoy the journey and hopefully enjoy the sound when done.

 

[chef free]

I measured what I could tonight, here's the breakdown.

Emit bank. 2.9 / 3.1 ohms
Midrange domes. 5.2 ohms
Midbass coupler, not original. 6.9 ohms
Rear tweeter. 6.2 ohms
Watkins Woofer. 2.1 ohms / 4.9 ohms

So I'm guessing everything driver wise is OK. If anyone thinks these numbers are bad please share your thoughts.

Thanks Much,
David.

Congratulations! Those numbers are perfect. I guess that "midbass coupler" is 8 ohms like the original. You are a lucky man, for sure; buy some lottery tickets or something!

 

[7.62]

Damn, well into the rabbit hole. Pics of the tweeter pot....

Thanks chef, I did a double treatment with deoxit and that's what you see here. The corrosion is all the way thru were the solder wires are connected.

I'd rather replace these but no luck finding a 5 ohm 25 watt unit yet, if anyone knows please post here.

 

[slimpikkins]

Amazon has them but they are big and open back. Look to be of better quality but you'll need to come up a way of covering the back. Glad all the drivers are in good shape.

 

[tubed]

Amazon has them but they are big and open back. Look to be of better quality but you'll need to come up a way of covering the back. Glad all the drivers are in good shape.

Excellent price and build.
I'd simply put them in a small ziplock baggie.

 

[tubed]

My curb alert QLS crossovers were a mess.
I re-positioned the inductors, cleaned the pots, replaced the push- on connector with a nice screw down connector rail, Dayton films/ film and foil bypass, and picked a nice single Clarity 2.8uf for the tweeters.

 

[7.62]

Tubed, thank you for sharing that, I may have a question or two after the pot issue is resolved. I don't like the inductors on top of each other. Definitely going to move them like you've done.

I've been looking at replacement pots, plenty of options out there. Slim, found the ones your talking about.

I'm going to take this original and drill out the tabs and just see if I can completely rebuild it using rivets but really to me that's a lot of moving parts, it has to somewhat corrupt the signal. Tommorrow I'm going to hit one of the electrical shops and look into getting instrument grade +/- 10% sealed 5/25 units. Not the cheapest option but I think maybe it'd be a good choice for the emit path.

The anticipation of hearing what I've been missing is awesome

 

[7.62]

Ok, completely disassembled. Hopefully you can see the green corrosion from the brass pins, this couldn't have been good in terms of degrading the signal. I can definitely rebuild these but have a question. I'm going to use aluminum type rivets to reset the pins on the spring and center disk.

What do you guys think, is there going to be any issue using Aluminuim rivets ? And fader lube ? This is the recommended lube for re-assembly.

 

[chef free]

I bought one of those open back, replacement pots. It seems lower quality that the originals to me. The windings are flat metal and not as nice as the spring steel in the originals. I think you are better off if you use the rebuilt originals.

I can't foresee any problems with using aluminum rivets. I re-assembled mine with generous amounts of FaderLube.

If you want to move the coils, make them line up in different directions, perpendicular to each other, since magnetic fields are directional.

 

[slimpikkins]

Wow! Drilling out the rivets. Mine were green, I wirebrushed them while cleaning them with "channel Master" great toxic stuff from the '70's. They are working ok but not great. Jaycar also sells a 5 ohm pot but is only 15watt. Suppose an 8ohm could be used also if they go down to zero as that is how the originals go 5-0...just would not use the full range of adjustment.
Jim

 

[JRhoBurton]

View attachment 900633 View attachment 900632 View attachment 900631 Tonight the first of the pair I purchased is out and in the office for cleaning,measuring and possibly recapping, reflowing the emits etc. I expect this to take a few weeks. First up will be removal of the woofer for refoaming then moving further into the speaker.

I know there's been so much information shared and I'll be using it as a baseline, but while I'm doing this if anyone wants any pictures of something specific I'll be happy to share. This should be No# 7001669 but the edges of the sticker were peeling and I pulled it back to reveal another sticker with the serial number 7001919. Kinda strange but both look like factory stickers. So for now I'm going with 7001669 & 7001670.

I'm sure I'm going to have some questions as I dig in, I respect your guys opinion. So here's no 7001669 /7001919 and some close up's of the mids and emits, they all look the same.

View attachment 900630

I only heard those once, long ago. I was considering buying a Kenwood KA-3500 amp and the guy at the store demo'd it for me on those speakers, to show that the amp had more oomph than you might expect. They might have been the smoothest speakers I I've ever heard.

Maybe if I pass thru Vegas some time after you're done, I could stop by and have a listen.

John

 

[tubed]

Here's a chart showing inductors at their theoretical worst and best positioning.
http://www.troelsgravesen.dk/coils.htmhttp://www.troelsgravesen.dk/coils.htm

I don't care much for my original pots and next time I'm inside the cabinet I going to just use 1 ohm wirewound resistors, perhaps zero resistance on the tweeters.

 

[jazzmans]

Do the rest of the emits look as good as the one in your photo? If so, then Awesome!
I finally have a day where I could come listen to them, and you've torn them apart... just my luck.
Well, maybe in June.

 

[7.62]

Thanks Slim, love the toxic stuff ! And Thanks tubed been down that road, for sure going to position them correctly and contemplating replacing, not sure yet.

Burton, as to listening you and any AK'er are more than welcome if your passing thru. That's what it's all about. Pm me anytime.

So here's today's progress. Woofers, these both measured very close. I tried refoaming with the supplied kit from the seller. The foams didn't feel right and the CRC glue was a pain in the butt. I decided to redo them after finding what consider the correct or closer foam. I ditched the glue and ordered the white glue from Parts express.
Just a brief description, stripped the new foams and glue. Major pain in the butt. Cleaned everything with gas and alcohol.

Prepped the cone and foam with the white glue, waited 3-5 minutes. Attached the surround and let tack. After 3-5 minutes I really went after it making sure adhesion was good. Kept after this for another 15 minutes.

Then glued the surround and let it tack for 3-5 minutes, ran the Woofer into the house and centered the voice coil using a 30hz tone. Back outside to finger the surround into place. Then cleaned and glued the trim ring into place.

Oh, jazzman yes all the emits and midranges are exactly as pictured on both speakers.

 

[7.62]

Pics are reverse order, dang it. Not to worry Jazz, might be worth the wait.

 

[7.62]

Well kinda bummed this morning, I was hoping to show a completely rebuilt factory pot. Went out a found the correct rivets to replace the brass pins, all was going well until the last pin. A little to much torque from the rivet gun and it broke the ceramic body in half . I guess it's replacement time.

 

[tubed]

Well kinda bummed this morning, I was hoping to show a completely rebuilt factory pot. Went out a found the correct rivets to replace the brass pins, all was going well until the last pin. A little to much torque from the rivet gun and it broke the ceramic body in half . I guess it's replacement time.

I hate it when that happens.
Now's the time to bypass them and tell us how they sound.
I'd like to know because I set my dials pretty much open.

 

[chef free]

Well kinda bummed this morning, I was hoping to show a completely rebuilt factory pot. Went out a found the correct rivets to replace the brass pins, all was going well until the last pin. A little to much torque from the rivet gun and it broke the ceramic body in half . I guess it's replacement time.

It's ceramic! Just Krazy Glue it.