JBL L65 Jubal revival

[kaz]

​I have a pair of L65/Jubals. Their cabinets are surprisingly good for their three decades of existence, couple of small veneer chips. Grills virtually perfect. Mids are fine. The 077's are glorious.
Now the downside. Of course the woofers' foam surrounds are rotten and deteriorated. The glass tops bear some scratches. The 'velvet' boards beneath the glass has also deteriorated with time. And one of my logo plate inserts has been lost in the sands of time as well. The chip/particleboard 'bases' show some rather obvious wear...corner joint expansion, chipping, worn paint. And I have never been real happy with the 'push spring' terminals on the back.
Here's my question(s):After having the woofers professionally refreshed with new surrounds, tested and a clean bill of health... what would be the next step? Work on the cabinet cosmetics? Rework the bases...or perhaps remove them all together? Heresy???
I have a great glass shop in town that can easily re-create the glasswork, probably improve it. I am currently working on a solution for the velvet board beneath. Any ideas brothers and sisters? And might anyone have a metal logo plate or two available? Please...
What would anyone think about replacing the spring terminals with more modern binding posts?
Am I missing anything???

I don't want to reinvent the wheel here, just restore a nice pair of speakers, but not wanting to miss an opportunity to improve them at the same time, while adding, not detracting from their value.
Your input is appreciated. Thank you.

[Hey19]

​I have a pair of L65/Jubals. Their cabinets are surprisingly good for their three decades of existence, couple of small veneer chips. Grills virtually perfect. Mids are fine. The 077's are glorious.
Now the downside. Of course the woofers' foam surrounds are rotten and deteriorated. The glass tops bear some scratches. The 'velvet' boards beneath the glass has also deteriorated with time. And one of my logo plate inserts has been lost in the sands of time as well. The chip/particleboard 'bases' show some rather obvious wear...corner joint expansion, chipping, worn paint. And I have never been real happy with the 'push spring' terminals on the back.
Here's my question(s):After having the woofers professionally refreshed with new surrounds, tested and a clean bill of health... what would be the next step? Work on the cabinet cosmetics? Rework the bases...or perhaps remove them all together? Heresy???
I have a great glass shop in town that can easily re-create the glasswork, probably improve it. I am currently working on a solution for the velvet board beneath. Any ideas brothers and sisters? And might anyone have a metal logo plate or two available? Please...
What would anyone think about replacing the spring terminals with more modern binding posts?
Am I missing anything???

I don't want to reinvent the wheel here, just restore a nice pair of speakers, but not wanting to miss an opportunity to improve them at the same time, while adding, not detracting from their value.
Your input is appreciated. Thank you.

Cosmetically, you can spray paint with flat black all non veneered areas. Back, bottom and baffle. Some Watco Danish Oil(Dark Walnut) really brings out the wood finish and fills in any light scratches. If scratches are deep, you may have to sand. Try turning the glass over if the scratches are on one side. When it is on the felt board, they may be hard to see. Heather suggested backing for picture framing. You may check a frame shop.Binding posts are your call. For me, they only have to be connected once, so I have left all mine original. Any painting you do, use blue painters tape and brown rolled painters paper to cover any areas needing protection.Since the baffle board is compressed wood, I wouldn't pull the drivers unless they need to be looked at. Sometimes it breaks. Metal logos are on Ebay if no one here has any. Good luck.

[kaz]

Thanks Hey 19 for your comments.

I have been on the lookout for suitable 'velvet board' material and frame shops and art supplies have been on my list of possibilities.

While I am in the 'refurbishing mode', are there any improvements to be realized, or perhaps experimented with, while the work is in progress?

I do use mine up off the floor, so I haven't had the dreaded boominess these speakers have been known for.

Another question... the user/instruction manual shows green to red woofer wiring and black to black, while the L65 technical manual/spec sheet shows the exact opposite on the N65 schematic, black via GREEN to the LF, and red via BLACK to the LF, although no LF transducer terminal colors or polarity is shown.
Which is correct?

[Hey19]

Thanks Hey 19 for your comments.

I have been on the lookout for suitable 'velvet board' material and frame shops and art supplies have been on my list of possibilities.

While I am in the 'refurbishing mode', are there any improvements to be realized, or perhaps experimented with, while the work is in progress?

I do use mine up off the floor, so I haven't had the dreaded boominess these speakers have been known for.

Another question... the user/instruction manual shows green to red woofer wiring and black to black, while the L65 technical manual/spec sheet shows the exact opposite on the N65 schematic, black via GREEN to the LF, and red via BLACK to the LF, although no LF transducer terminal colors or polarity is shown.
Which is correct?

Here is the link on this site for all Jubal model schematics.http://www.audioheritage.org/vbullet...6&d=1144944024

[doodle6]

Thanks Hey 19 for your comments.

I have been on the lookout for suitable 'velvet board' material and frame shops and art supplies have been on my list of possibilities.

Black velvet cloth attached with spray adhesive to the original cardboard. I've found NOTHING that matches the original fuzzy board at fabric, craft, hobby, or frame shops.

[Hey19]

Black velvet cloth attached with spray adhesive to the original cardboard. I've found NOTHING that matches the original fuzzy board at fabric, craft, hobby, or frame shops.

I may try that on mine. Where can I get some?

[tesla]

From my looking at the black "fuzz'


I think it is very thin black foam.

I may try that on mine. Where can I get some?

[kaz]

From my looking at the black "fuzz'I think it is very thin black foam.

You know, you may be right.I recalled it to be soft and 'velvet-ty'.My 'fuzz' is falling away, much more on floor than on the board.

[tnsilver]

Hi there, I've made this post today, in this older thread, with this thread in mind (I actually planned to post it here but got confused by the similarity in content). You can check out this 4311 restoration project to get some ideas.

Cheers
Tom

[doodle6]

I found the stuff at a local mom and pop fabric store - you know, the kind that old geezers visit to pick up chicks in their 60s. You should be able to find one with an internet search for "craft store", "fabric store" or "sewing store".

I may try that on mine. Where can I get some?

[Audiobeer]

When I restored my JBL L-65 years aso the black velvet matting was found at a local frame shop. Had them cut it to the exact size. I had to go around the border and black that out the edge with a black magic marker as the edges showed through as white. Looked great.

[Juballen]

Hi everyone. This is my first post on this forum (any forum actually) so pardon if I commit any mistakes. I assure you they are unintentional. In searching for the "flocked black fuzzy stuff" that basically falls off the "shirtboard" under the glass top on the Jubals I found this stuff. It's called "Flocking Material" and is available from www.scopestuff.com. Item #FLK2. A free sample will be mailed to you if requested from them. It has an adhesive backing that allows it to be applied to the shirtboard. I ordered the 23.5" x 47" size since the smaller 12" wide material left no room for error in alignment.

It's used to line the inside of telescopes to eliminate internal refelections and it does an admirable job. I used a medium grit sand paper to remove the old, dried adhesive from the shirtboard and applied the FLK2 Flocking Material directly to it. Then used an exacto knife to trim off the excess and trim the rectangular hole for the JBL metal badge. The FLK2 is quite thin so I purchased a 15" x 20" Ultra Black (black all the way through) art/craft board from Michael's Craft Store SKU #93924182945 to bring the total thickness back up to close to the original I think. The glass actually sits a tad above the wood rim by about .015 to .020" but it suits me. The Michael's board is .055" thick so if you want it flush a .040" thick (1 mm) board would be real close if you can locate one.

Cutting the rectangle in the craft board was about the hardest part of the whole deal. I made 3 practice cuts before attempting the real cut. I used a piece of felt under the badge to bring it right up to the glass without causing it to actually lift the glass.


This may be overkill but my feeling was that the original JBL idea was to look into the glass and have it appear as a black abyss with no reflections. Just the JBL badge "floating" in space so to speak. The ScopeStuff flocking material does exactly that.


The bad news is it's pretty expensive. The FLK2 was $29.00 including shipping and the art board was $5.00 each. So for $20 per speaker I have what I think is the closest thing I could find to the "original" look.

I'd be happy to answer any questions anyone has about this. I will say that an extra pair of hands would come in handy and be sure your cutting blades are new and sharp. That art board is particulary tough.

My next project is to replace the MDF bases that have swollen from moisture with real wood, probably oak. In the meantime, happy listening!

[SEAWOLF97]

I had some Jubals ....the base: they are already too close to the floor on factory bases , removing them could make bass even more boomy. If they are poor shape, I'd paint them black, or you could remove them if you plan to get the whole speaker up higher.

binding posts: factory ones WILL break, if they haven't already. I'd replace them, esp. if you want to use larger gauge wire.

logo plates: I had an extra with the post mount. just broke off the post and it fit right in.

fuzzy board: mine was falling apart when touched, so I didn't.

[Juballen]

I agree. The Jubals sound better when elevated above the floor. Putting the midrange at about the same height as your ears seems to work best for me. I think JBL realized this boomines problem because when I lifted them up I really had to turn down the "PRESENCE" AND "BRILLIANCE" controls. I'm really only interested in renewing the original bases to do just that. Keep them original. Mine are swollen, chipped and generally shot. Although I will substitute oak for MDF.Then I plan on building steel or aluminum stands to get the proper total elevation.

Does anyone know if the the original bases are screwed to the bottom from inside the cabinet? I haven't figured out if they are just glued to the bottom or glued and screwed.

[warpig]

This is what I did with my networks. This was for a set of Jubals not the A or B model. Also my 126 woofers went out and due to not being able to find recone kits for the 126 woofers I purchased some 128H-1 woofers. If you do this you need to switch the positive and negative wires on the woofer. Change the wire configuration Black on the black post of speaker and green on red post of speaker.

One of my LPADs went out recently so while replacing all 4 LPADs I decided to bypass the caps with the .01uf Theta caps. They are still breaking in but first impressions are positive.

I know a lot of purest will not like what I have done but I will say this, the sound is fantastic over the stock configuration. Though they may never be as valuable having being modified I will never sell them and they sound so great in my system in my room every time I listen to them I just smile.

With that being said there are a lot of experts in here and by no way do I claim to be one. But every time I turn on the stereo I smile.

Jantzen 3.9uF 800V Z-Superior CapacitorPart # 027-488

Jantzen 1.5uF 800V Z-Superior CapacitorPart # 027-478

Ampohm 8.2uf forgot where I purchase them from.


Mills 20 Ohm 12W Non-Inductive ResistorPart # 005-20

Speaker L-Pad Attenuator 15W Mono 1" Shaft 8 OhmPart # 260-250

Erse 1.00mH 16ga FoilQ - .407Ω 500W - Copper Foil Air Core Coil.

Erse 0.50mH 16ga FoilQ - .243Ω 500W - Copper Foil Air Core Coil.

Reused part number 52728.

027-700_ALT_0.jpg

Then I bypassed the Caps with Audiocap PPT Theta 0.01uF 600V Film/Foil Capacitor
Part # 027-700 Its still breaking in.

Please anyone if I have given bad information here such as switching the wires please correct me. As I said I am not the expert and am learning. I just love the sound of these speakers.

Thanks All
Happy New Year