AR 4x Cap wiring question... Three wires ?? Blue Green BLACK (Continued)

[GD70]

Thanks for the advice Glenn, and here are some pics Stupidhead.

I haven't gotten around to thinking about refinishing yet and don't know which route I'll take. They are a little rough but not terrible.

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The caps finally arrived and I've been busy Installing them. I started by wiring the pots outside of the cabinets and attaching the 20uF cap. I wired the two 12uF NPE's together ouside the box then began assembly inside. I layed foil down to protect components while soldering .

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I read that others recommend wrapping the HF pot in plastic or covering it some how to shield it from fiberglass but also read that it needs to breath to dissipate heat. Here's what I came up with using some left over speaker surround glue and a bit of vinyl screen I had laying around. The screen is not glued to the pot.

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Here is the finished crossover inside the box less wire keepers and fiberglass stuffing.
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All of my connections are soldered and shrink wrapped with the exception of the three blue wires which are soldered and crimp capped.

Your crossover work looks fabulous! Just make sure you put dielectric grease on the contact disk, pot wiper, and coils in the pots to help prevent future corrosion.
The cabs can be repaired to look almost new.
First, sand the finish off to the veneer. Veneer pieces can than be cut and the corners can be patched.
If you look at any of my restoration projects, you can see how to do this easily. You'll need to have some veneer on hand, preferably old, and possibly from another speaker that can be a veneer donor.
Once completed, applying the oil will help blend in the repaired areas.
Glenn

 

[uenjoymyself]

The wire keepers are screwed down and packed with a wool dampening material which was excess from when I replaced the crossover in a JBL .003 load barzilay cabinet. I found it easier to work with than the fiberglass in this instance. All of the wires which come in close contact with the cabinet were treated to avoid buzzing and rattling. I will wrap and pack the remaining wires with fiberglass.




Which leads me to my next question. CSP indicates different weights of fiberglass for early and later models . The earlier models used 18 oz while later models used 12oz. This apparently was due to the different inductors used in different productions of the AR4x.

I assume by the marking on the inductor in my cabinets, and previous posts confirm, that it has 265 turns which is not a #4 or #5.

I removed exactly 16 oz of fiberglass insulation from my cabinets. Would it suffice to replace the exact amount or should I do further research to determine a specific amount based on the size of the inductor.

I know it should be a no brainier but...

I tend to get a little OCD after reading so much information regarding the topic of re stuffing. Which materials to use, weights, measurements of fiber diameter and graphs of how these effect... Q?

Apparently it makes a difference.

EDIT: Also, does the fiberglass need to be shredded and fluffed before stuffing or does it go in as pictured at CSP AR3a restoration by stacking square slabs to fill the chamber?



The fiberglass in my cabinets was found as follows: The walls floor and ceiling were lined with like sized aprox 3/4 inch thick fiberglass slabs and the remainder was filled with shredded and fluffed fiberglass. One of the cabinets had a 3/4 inch slab dividing the cabinet between the woofer and tweeter.

Recommendations before I proceed?

Thanks,
Uenjoy

 

[uenjoymyself]

Your crossover work looks fabulous! Just make sure you put dielectric grease on the contact disk, pot wiper, and coils in the pots to help prevent future corrosion.
The cabs can be repaired to look almost new.
First, sand the finish off to the veneer. Veneer pieces can than be cut and the corners can be patched.
If you look at any of my restoration projects, you can see how to do this easily. You'll need to have some veneer on hand, preferably old, and possibly from another speaker that can be a veneer donor.
Once completed, applying the oil will help blend in the repaired areas.
Glenn

Hi Glenn,
Thank you for your kind words and expert advice.
I did in fact clean and treat the pots.They were in pretty good shape and cleaned up well. I soaked them in distilled white vinegar and salt solution to remove a very small amount of green crust from the two posts that connect to the coil. With a soft wire wheel and dremmel, I cleaned the posts and a small amount of tarnish from the contact disk and wiper. I then followed with a light coat of dielectric grease, using a paint brush, to all contact surfaces and to the coil. The contact disk was free of pits and polished up nicely, as did and the pot wiper which had a robust contact tip.

Uenjoy

 

[GD70]

Hi Glenn,
Thank you for your kind words and expert advice.
I did in fact clean and treat the pots.They were in pretty good shape and cleaned up nicely. I soaked in distilled white vinegar and salt solution to remove a very small amount of green crust from the two posts that hold the coil and with a soft wire wheel and dremmel cleaned a small amount of tarnish from the contact disk and wiper. I then followed with a light coat of dielectric grease using a paint brush to all surfaces and the coil. The contact disk was free of pits and polished up nicely and the pot wiper had a robust contact point.

Uenjoy

Good to hear it. More often than not, the pots are beyond repair, though some have had success flowing solder onto the disk, and sanding the surface smooth, as well as filling the worn away wiper tip with solder.

 

[baco99]

Good to hear it. More often than not, the pots are beyond repair, though some have had success flowing solder onto the disk, and sanding the surface smooth, as well as filling the worn away wiper tip with solder.

I never would have thought of that. Good suggestion!

 

[ra.ra]

Nice work you're doing there - - I haven't traced every wire, but the crossover layout and installation looks very good. Am pleased to see you used a film cap for the tweeter and NPE's for the woofer circuit - - good choices. Also noticed in your final pic in post 20 that the inspector has been inside - - I always like to see him in there.

About the coil, yes, the 265 coil is different from the typical #4 or #5 and was used when this woofer (yellow, non-circular basket) made its way into the 4x cabinet. I don't recall the different weights of insulation used in the 4x, but I'd suggest simply trying to re-stuff the original amounts in a fashion which follows the original installation. With the additional padding you've used under the wire mount screws, you're already adding a small bit of stuffing weight. I'll be more curious to hear how the speakers compare using the two different woofers.

 

[uenjoymyself]

Nice work you're doing there - - I haven't traced every wire, but the crossover layout and installation looks very good. Am pleased to see you used a film cap for the tweeter and NPE's for the woofer circuit - - good choices. Also noticed in your final pic in post 20 that the inspector has been inside - - I always like to see him in there.

About the coil, yes, the 265 coil is different from the typical #4 or #5 and was used when this woofer (yellow, non-circular basket) made its way into the 4x cabinet. I don't recall the different weights of insulation used in the 4x, but I'd suggest simply trying to re-stuff the original amounts in a fashion which follows the original installation. With the additional padding you've used under the wire mount screws, you're already adding a small bit of stuffing weight. I'll be more curious to hear how the speakers compare using the two different woofers.

View attachment 799358

Hello rara,

I was wondering about him, and yes I have subtracted the extra weight of the padding from the total fill amount. I re stuffed with fresh yellow fiberglass to equal 16oz in the same way I found it.

Thank you for your input and comments throughout!

I have to say that the recap has made a profound improvement in sound quality! I am very happy with the results. I chose to use Clarity caps for the HF. I have nothing to compare them to but feel comfortable in spending the extra $ since the investment I made to acquire the speakers was minimal. I'm happy with my choice!

My Impression on sound regarding the different drivers:

The non circular yellow surround woofer seems to sound a little better in the low and mid frequencies, just a little cleaner and more detailed all around but the difference is subtle. I'm also biased since I know that that driver matches better with the dual cap crossover as explained in earlier posts. I perceive no difference in the high frequencies of either speaker.

The circular black surround woofer seems slightly subdued in the lower end and mid seems to lack some sparkle. The excursion of the cone is greater than that of the non circular. I notice that the travel (in and out) is notably different during heavy bass passages, at higher volume levels, than that of the non circular.

What might one attribute the behavior of the circular woofer to. Dual cap configuration never meant to be matched to that driver or that I shorted one of the 12uF caps during installation and the signal is being passed through only one of the 12's changing the crossover point? In my quest for the perfect crossover, while re routing a wire, I cut the zip tie that held the two 12uF caps. In doing so, while squeezing the snips, my wrist twisted slightly causing a very small ding in the side of one of the caps

While both speakers sound fantastic and the difference in SQ is slight ( BTW both sound perfectly matched in mono) I have to wonder, should I replace the very slightly dented cap? If shorted is that causing the woofer to behave differently?

EDIT: Listening now, in a more relaxed less critical state than I was in last night after completing the work, I realize that these speakers sound freaking amazing! I cant imagine that I damaged a cap, they just sound so sweet.

The only difference being the travel of the circular woofers cone... at high volume.

Thanks,
Uenjoy

 

[GD70]

Glad to hear they are sounding great! They are wonderful speakers.
Now, onto the cabs!
Glenn

 

[ra.ra]

Yeah, am also happy to hear that things have worked out. I doubt very much that you have damaged the new 12uF cap, and it sounds unlikely that performance would be affected simply from a surface imperfection. Regarding differential woofer cone movements, I have sometimes observed this even with matching woofers, but in your case, it could be that the suspensions (surround and spider) of the two woofers have somewhat different compliance.

 

[uenjoymyself]

Oh man! I cant believe I didn't follow up on this thread. I have been thoroughly enjoying the 4x's after the recap! Thanks to everyone for their help. Happy Holidays to you and everyone on AK!

Cheers,
Uenjoy

 

[GD70]

Same to you and happy listening in the New Year!