250 Ti clone project

[Woody Banks]

I just completed a trade with a good friend for a pair of L250's. Included in the swap were the upgrade kits to convert to 250Ti's. Instead of converting the L250's I have decided to leave them intact and build clone cabinets for the 250Ti. In my quest for the necessary woofers to complete the component list I found a complete set of 250Ti BM's in need of cabinets. A month later,I was also able to pick up a set of LE14H-3's. So instead of building a single pair of clones, I will be attempting to build two pair this winter. I will try to remember to take a few photos of the process.

[BMWCCA]

I will try to remember to take a few photos of the process.
Knowing your past work, these will not be clones but they'll be an improvement and a pleasure to look at. :applaud:

I'll be they're not the asymmetrical tilted towers we're used to seeing!

Next I hope you'll tackle a pair of 1400 Arrays!

[svollmer]

I will try to remember to take a few photos of the process.

Please don't "try."

DO IT!

We wanna see the entire process and learn from it!!! :applaud:

[Robh3606]

I'll be they're not the asymmetrical tilted towers we're used to seeing!


Well if they are not the stock networks may not work as well as they should. Changing the baffle and the driver spacing means potentially changing the network. The baffle slope was an integral part of the design.


Have fun doing it. I had fun doing mine.

Rob:)

[BMWCCA]

Well if they are not the stock networks may not work as well as they should. Changing the baffle and the driver spacing means potentially changing the network. The baffle slope was an integral part of the design.

You can time-align without the leaning-tower-of-Pisa look! No horns makes it even easier.

The 250 could easily have been a rectangle, though that might have left useless extra space in the upper end. Granted, network changes may be on order simply due to any change in box size alone. My point was that Woody's work is always beautiful and his interpretations have their own sense of style that frequently depart from the JBL aesthetic!

Most likely won't be black ash, either. ;)

[Robh3606]

My point was that Woody's work is always beautiful and his interpretations have their own sense of style that frequently depart from the JBL aesthetic!


Yes he does. But form in this case is an important aspect of the design so if you change the form be prepared. Not saying you can't change things but it helps if you know why things were the way they were. With that knowledge you can explore other options with the reason for the original design at hand and go from there. Never a good idea to change things without understanding the original. Anyone doing a clone of them should read the L250 design brief. It's a bit buried so I will drop a link to it.

http://www.audioheritage.org/vbulletin/showthread.php?4556-L250

Rob:)

[rdgrimes]

The 250 could easily have been a rectangle, though that might have left useless extra space in the upper end.

I disagree. The cab is designed with a purpose. It could have been a difference shape, but not a rectangle.

[Amnes]

Woody, if you may clone the cabs. They are sexy as hell!

[Woody Banks]

Woody, if you may clone the cabs. They are sexy as hell!


I agree! I will stick with the original design shape this time but will be using Baltic birch instead of particle board and will probably pick something like Bubinga or Paduk for the veneer.
Here is a photo of the older Ti crossover compared to the later Ti BQ and a shot of the L250 after unpacking.
BTW Forward Air did a great job of shipping both of the pallets of JBL's from Oregon to Mich. @ a resonable rate to boot.

[opimax]

Hi Woody,

in my tests the TIBQ Xover sounded the best in stock form in my TIs

Mark

[gmarascortt]

Hey Woody.....

How is this project coming along?

If I can't find another set of 250Ti's right away, maybe I will buy a set of clones from you!

LOL!

[Woody Banks]

Hey Woody.....How is this project coming along? If I can't find another set of 250Ti's right away, maybe I will buy a set of clones from you! LOL!The project was put on hold for a bit due to carpal tunnel surgery last week. Maybe this will also help with my "fecal touch syndrome". Lately everything I touch turns to shit! Cabin fever will be sure to get be back in the woodshop later this week. I was glad to hear that you were able to get your money back from that attempted ebay screwing on the 250Ti's.

[JuniorJBL]

I sure like "L" 250 cab's just a bit better. No grill plugs.:applaud: They sure are pretty!;)

[I want TAD]

Good work~~

[audiophile.1963]

55572

[hjames]

daleks!!


http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=55572&d=1335131122

[Woody Banks]

I was finally able to actually start on the clone project this week. The first thing I did was to build a saw guide for the ole Skill 77. The table saw proved to be almost useless because of the odd shapes needed for these cabinets.

[4313B]

Very nice!


The table saw proved to be almost useless because of the odd shapes needed for these cabinets. Yep. :p

[JuniorJBL]

What have you got planned for the tweeter rings?

Nice job woody!!

[badman]

What have you got planned for the tweeter rings?

Nice job woody!!

The tweeter rings could be improved- the hard transition to the bulb is not ideal. It'd be better if the rounding transitioned smoothly to the tweeter flange, so there's an opportunity to add a little flair.

[Woody Banks]

The tweeter bezels are without doubt the most difficult part of the clone process. My first thought was to attempt to turn them on the lathe but my skill level is not up to task. " A guy has to know his limitations". :D I will fabricate a jig system for the router table and see how that goes. To reduce the tendency to crack, I will laminate the material instead of using a single piece. I am probably going to use Jatoba (Brazilian Cherry) on one pair and maybe Rosewood or Bubinga on the other.

[Robh3606]

I will laminate the material instead of using a single piece. I am probably going to use Jatoba (Brazilian Cherry) on one pair and maybe Rosewood or Bubinga on the other. That's what I did although mine were going to be painted so that made it alot easier.Rob:)

[JuniorJBL]

Greg did tell me at the GTG that they were a bear and the guy who made them came up with a very good way to make them and then cut them at a 15deg angle like Rob has done above. There were no CNC machines at that time!!

Nice job Guys!!:applaud:

[Mr. Widget]

Greg did tell me at the GTG that they were a bear and the guy who made them came up with a very good way to make them and then cut them at a 15deg angle like Rob has done above. There were no CNC machines at that time!!

Nice job Guys!!:applaud:I would recommend that anyone using Rob's rather clever and fairly simple method use a round nose router bit with a 1/2" shank if you can.


Widget

[Woody Banks]

Rob, I really like your jig system. That sure beats the ole brute force belt sander method. Thanks for sharing.



I would recommend that anyone using Rob's rather clever and fairly simple method use a round nose router bit with a 1/2" shank if you can.


Widget

Widget, that's a great tip. I just happen to have a set of round nose burr bits from a duplicator project.

[Robh3606]

Hello Woody

Your welcome I can't wait to see how yours come out. Your horns are always beautiful so I am sure these will be mint!

Rob:)

[gmarascortt]

Hey Woody...
Glad to see you are able to start working again on this project, and they look awesome so far!
Thanks again for taking time out to fabricate for me my "clone" 250 Ti grill frames!

[Woody Banks]

After loosing momentum I was finally able to slap a coat of oil on a finished 250 cabinet. Another year or so and I will have those babies ready to go.

[svollmer]

Absolutely WOW! They look fantastic. Can you share with us how you install the quarter round molding on the cabinets? Do the panels leave gaps for the moulding to be installed, or is the moulding integral to the panels?

Obviously, these are questions from a complete novice. :o:

[JuniorJBL]

Very nice job Woody!! Those should do nicely along side the originals!!:D

[Woody Banks]

Absolutely WOW! They look fantastic. Can you share with us how you install the quarter round molding on the cabinets? Do the panels leave gaps for the moulding to be installed, or is the moulding integral to the panels?

Obviously, these are questions from a complete novice. :o:

Thanks!
I decided to install the moldings in the final stage. This allowed me to use the router to trim the veneer. Not all of my attempts of producing the quarter round molding was successful. Jatoba because of its hardness is also brittle and can chip-out and leave you with firewood. This would have been fairly catostrophic if the molding was already in place. There may be a way to use a roundover bit if the molding was integral to the panel but I have my doubts. Compound angles made me drag out the ole wood rasp at one point.

[SEAWOLF97]

After loosing momentum I was finally able to slap a coat of oil on a finished 250 cabinet. Another year or so and I will have those babies ready to go.

Woody ... very nice work so far. You and I both missed the pair of 250ti's with a BIN of $999 last week in Newberg. :(

http://www.ebay.com/itm/JBL-250-Ti-Loudspeakers-Excellent-Condition-Classics-from-1985-/181056721698?ssPageName=ADME:B:SS:US:1123&nma=true&si=EB1c6YruGzT8MMOddl7okkItPGk%3D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557

(I have a message in to the seller in case the sale falls through ..
(thx Punch for the pointer))

I hope you address the issue that all L250/250Ti owners have ....the veneer comes down soo low that moving them on carpet snags & strips the veneer. when you damage the beautiful wood just by moving them , well ...thats a big "Oh Sheet" :eek: moment.

There are a couple of threads here on that issue.

http://www.audioheritage.org/vbulletin/showthread.php?22719-Preserving-250ti-veneer-skirts&highlight=

[Amnes]

nice!

[Woody Banks]

[QUOTE=SEAWOLF97;342168]Woody ... very nice work so far. You and I both missed the pair of 250ti's with a BIN of $999 last week in Newberg. :(

http://www.ebay.com/itm/JBL-250-Ti-Loudspeakers-Excellent-Condition-Classics-from-1985-/181056721698?ssPageName=ADME:B:SS:US:1123&nma=true&si=EB1c6YruGzT8MMOddl7okkItPGk%3D&orig_cvip=true&rt=nc&_trksid=p2047675.l2557

WOW! I would have jumped on them like a "chicken on a june bug" and saved myself a bunch of effort. My wood shop is usually colder in the morning than the outside temp. I am hoping that my taller glides will help resolve the veneer issue.

[rdgrimes]

The only real problem with the veneer on the 250s is the exposed particle board on the bottom edges. As it ages and dries out the veneer gets sloughed off. Even a thin strip of ply or just veneer on the bottom edges - property sealed - will eliminate that issue. And it would be invisible.

[Woody Banks]

I finally was able to put the finishing touches on the clone project. I diverted as usual and used magnets instead of sockets for the grill attachments. The photo flash makes the grill cloth color appear a lot bluer than in real life. In normal light they appear almost black. I will attach the JBL badges before I power them up.:D

[srm51555]

Wow awesome work!!

[grumpy]

:applaud:

[Odd]

As always wonderful woodwork!

[JeffW]

They look perfect, even has the LE14H-3 woofer it appears.

[gmarascortt]

Absolutely beautiful!!:applaud:

[svollmer]

Absolutely fantastic work.

Where do I send my deposit for the next pair? :applaud:

[dprice]

Well worth the wait! :D

[Woody Banks]

They look perfect, even has the LE14H-3 woofer it appears.

Thanks Jeff. Very keen eye spotting the woofer upgrade. :)

[Woody Banks]

Absolutely fantastic work.

Where do I send my deposit for the next pair? :applaud:

Thanks but I have learned my lesson. :nutz:

[JeffW]

Thanks Jeff. Very keen eye spotting the woofer upgrade. :)


I bought a pair of LE14H-3s to stick into my 250Tis, but never got around to messing with it before trying something different...so I had a "mind's eye" picture of what to expect :)

[BMWCCA]

I bought a pair of LE14H-3s to stick into my 250Tis, but never got around to messing with it before trying something different...so I had a "mind's eye" picture of what to expect :)
And, what did you do with them??

[JeffW]

Storage shed, with all the other misfit toys.

[JuniorJBL]

Fantastic job Woody!! Those are truly fabulous!! :applaud: