JBL L200/300 restoration help.

[retox]

I picked up a pair of barn condition L200's this past weekend.
They were converted to the L300 configuration from what I can tell.
I am by no means an expert on either model and could use some guidance on my restoration project.

The cabinets are toast, they got wet and I think that mice may have claimed them as a home for awhile.

I cleaned the pots and connected them you an amp and played some music from my phone and they sound very good.

Here is what I have in the way of drivers and network.

Woofer - LE15B
Mid - LE85
Tweeter - 077
Net work - LX16 and N7000

I am thinking of keeping the same volume as the L200 including the slope and doing L300 cosmetic approach including the rounded top edge and glass top.
My goal is to keep the cost down, but do a really nice restoration. I will use MDF and a Formica face, top, bottom, and rear with a wood veneer for the sides.
I just want any thoughts on this approach.

I will try to post some pictures soon.

Thanks in advance...

-retox

[HCSGuy]

Do whatever is easiest and looks best to you. There is no resale value in cabinets, and if you need money, you’ll get the most simply by parting the drivers and crossovers out on eBay and taking the cabinets to the dump. Because of this, you may also try watching Craigslist for cabinets. I got a pair of really nicely restored L200 cabinets of CL for $225 - previous owner had already sold the parts out of them, and I had my dad’s LE15/LE85 that went right into them.

Fwiw, I would also consider not using the original crossovers - build your own with better components, or go bi-amp/tri-amp with an active crossover. JBL M553 crossovers are inexpensive, though extra power amplifiers may not be. My dad’s setup sounds completely different, and much better, even through a cheap active crossover.

[tjm001]

I picked up a pair of barn condition L200's this past weekend.
They were converted to the L300 configuration from what I can tell.
I am by no means an expert on either model and could use some guidance on my restoration project.

The cabinets are toast, they got wet....

I will try to post some pictures soon.

Thanks in advance...

-retox

Some good pictures would help to decide if the cabinets are absolutely for sure totaled.

[nedseg]

If you have the N7000/N8000 crossover and 077 tweeter upgrades like I had done in the 70s, you might find my post here interesting.
https://audiokarma.org/forums/index.php?threads/old-vs-new-jbl-2216-le15b-vs-jbl-2216nd-1-in-l200s.830641/
Also, there are tons of posts here by others on the L200 topic.
Welcome to the L200 'club'!

[retox]

85286
If you have the N7000/N8000 crossover and 077 tweeter upgrades like I had done in the 70s, you might find my post here interesting.
https://audiokarma.org/forums/index.php?threads/old-vs-new-jbl-2216-le15b-vs-jbl-2216nd-1-in-l200s.830641/
Also, there are tons of posts here by others on the L200 topic.
Welcome to the L200 'club'!


Here are some pictures of the cabinets. What you don't see is the smell...possibly cat pee.

85283
85284
85285
85287

[nedseg]

Talk about rid hard and put away wet!!
Ugh.
Just for general knowledge, not that you should try to rehab those, but I've found OdorMute to be the only product that effectively gets rid of cat pee scent.
I like the Formica idea - they make a lot of nice variants today.
Maybe match with a Corian baffle? :bouncy:

[Mr. Widget]

Fwiw, I would also consider not using the original crossovers - build your own with better components, or go bi-amp/tri-amp with an active crossover. JBL M553 crossovers are inexpensive, though extra power amplifiers may not be. My dad’s setup sounds completely different, and much better, even through a cheap active crossover.I'll second that. The JBL crossovers of the day made exceptional drivers sound pretty standard in my opinion.

I would seriously consider different woofers too if you can, but even if that is not a possibility, you have the basic building blocks for a very rewarding system.


Some good pictures would help to decide if the cabinets are absolutely for sure totaled.Having looked at the photos, I am sure there are those who would do a restore, I would do a new build.

If you prefer the L300 look then go that route. All you need is a solidly built 5 cu ft box with ample bracing and you are off and running.

Have fun, please keep us posted, and welcome aboard!


Widget

[retox]

Talk about rid hard and put away wet!!
Ugh.
Just for general knowledge, not that you should try to rehab those, but I've found OdorMute to be the only product that effectively gets rid of cat pee scent.
I like the Formica idea - they make a lot of nice variants today.
Maybe match with a Corian baffle? :bouncy:


Might as well throw in the kitchen sink...:dont-know:

[macaroonie]

http://www.audioheritage.org/vbulletin/showthread.php?17238-Backyard-Box-Building-The-Build

MDF is horrid , stay away ,just sayin. M

[retox]

http://www.audioheritage.org/vbulletin/showthread.php?17238-Backyard-Box-Building-The-Build

MDF is horrid , stay away ,just sayin. M

It appears that the original cabinets are made of particle board and veneer. What material are you suggesting?

[Ian Mackenzie]

I picked up a pair of barn condition L200's this past weekend.
They were converted to the L300 configuration from what I can tell.
I am by no means an expert on either model and could use some guidance on my restoration project.

The cabinets are toast, they got wet and I think that mice may have claimed them as a home for awhile.

I cleaned the pots and connected them you an amp and played some music from my phone and they sound very good.

Here is what I have in the way of drivers and network.

Woofer - LE15B
Mid - LE85
Tweeter - 077
Net work - LX16 and N7000

I am thinking of keeping the same volume as the L200 including the slope and doing L300 cosmetic approach including the rounded top edge and glass top.
My goal is to keep the cost down, but do a really nice restoration. I will use MDF and a Formica face, top, bottom, and rear with a wood veneer for the sides.
I just want any thoughts on this approach.

I will try to post some pictures soon.

Thanks in advance...

-retox

Here are some reference threads to get your head around the options.
Looking at the crossover network as a starting point check what horn you have? If it’s the short horn then your looking at a 1200 hertz crossover point for the horn. The longer horn sans the L300 has a crossover point of 800 hertz. Remember the equivalent L300 schematic is set up for the 2235H woofer and the 800 hertz crossover point. So that won’t work with the short horn. Assuming you have the LE15B and the LE85 with the shorter horn it’s a matter of taking the voltage drive of this network

http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=157&d=1055105053

and then adding the 8000 hertz Low pass crossover to form a band pass filter. Then add the L300 077 high pass filter.

On the enclosure l suggest you shoot for 5 cu ft3 then if you do change the woofer out you can use the 2235H or the 2216nd or the 2216nd-1.






http://www.audioheritage.org/vbulletin/showthread.php?166-4333-S300-L300-equivalent-bandbass-circuit&p=1042#post1042

http://www.audioheritage.org/vbulletin/showthread.php?31473-Please-advice-for-JBL-Crossover

http://www.audioheritage.org/vbulletin/showthread.php?2602-Help-Upgrade-Woofers-On-L200

http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=157&d=1055105053


http://www.audioheritage.org/vbulletin/attachment.php?attachmentid=158&d=1055105118

[macaroonie]

It appears that the original cabinets are made of particle board and veneer. What material are you suggesting?

Baltic Birch Ply

[retox]

Baltic Birch Ply


After thinking about a going forward plan, I decided to refinish the cabinets and clean, paint and rewire using all the existing parts.
Once they are back in action do some upgrades starting with the woofers.

85322

After I complete the upgrades I may build new cabinets, but to be honest, looks aren't everything...

Some more questions, do most of you who have restored the L200/L300s use fiber glass insulation for the batting?
Do you all normally repaint the 077 tweeter outer housing and flange if they are a little scuffed up?

-retox

[1audiohack]

...One more question, do most of you who have restored the L200/L300s use fiber glass insulation for the batting?

-retox

I do. I’ve not used anything else.

Barry.

[jmpsmash]

I do. I’ve not used anything else.

Barry.

Do you just use the stuff from hardware store? Are you concerned about the fibers getting into the air with all the vibration?

[jmpsmash]

It appears that the original cabinets are made of particle board and veneer. What material are you suggesting?

second on Baltic Birch Plywood. You cannot find those in the generic big box hardware store. Instead I found good quality one from lumber store. Highly recommend 1" (actually, 24mm).

[1audiohack]

Do you just use the stuff from hardware store? Are you concerned about the fibers getting into the air with all the vibration?

I bought a 4’ X 100’ roll of the stuff JBL uses /used from CTI? I am down to the point where I should order another. I will have to see if I can remember for sure where it came from.

I don’t sweat airborne fibers. They are heavy.

Is glass a carcinogenic in CA now? ;)

Barry.

[Mr. Widget]

Is glass a carcinogenic in CA now? ;)
Yeah, but luckily you are in Nevada so no need to worry. It is only a carcinogen in CA. :D

Seriously, I doubt the particles are small enough to be a carcinogen, but I bet it is still quite unhealthy to breath the stuff. The stuff JBL uses/used and the Wrapon stuff I use is fairly non-shedding, but if coaxed, I imagine you can get some of it airborne.


Widget

[Ian Mackenzie]

Simply wear a face mask during installation.

It’s only a problem when you start cutting or tearing apart the fibre glass.

[retox]

Simply wear a face mask during installation.

It’s only a problem when you start cutting or tearing apart the fibre glass.


I will wear protection...I worked with fiberglass insulation when I was a lot younger.

[retox]

After thinking about a going forward plan, I decided to refinish the cabinets and clean, paint and rewire using all the existing parts.
Once they are back in action do some upgrades starting with the woofers.

85322

After I complete the upgrades I may build new cabinets, but to be honest, looks aren't everything...

Some more questions, do most of you who have restored the L200/L300s use fiber glass insulation for the batting?
Do you all normally repaint the 077 tweeter outer housing and flange if they are a little scuffed up?

-retox

I drew up the wiring diagram as I understand it. This was wired by the original owner and so I wanted to have you all take a look at it for any mistakes.
Also,I believe the Green and Red wires terminated at the Red posts on the drivers. Is this correct? Red is the positive side of the drivers, is green the positive wire?
See the attached PDF

Thanks

-retox

85341

[nedseg]

Your diagram shows the same color/connections as mine were done (by a JBL Pro tech) when I had them add the N8000/077s.
(I don't use the LX16 anymore, am bi-amped directly to the new woof and the N8000.)

[retox]

Your diagram shows the same color/connections as mine were done (by a JBL Pro tech) when I had them add the N8000/077s.
(I don't use the LX16 anymore, am bi-amped directly to the new woof and the N8000.)


Thanks, I feel better about taking them apart and putting them back together.

[short_circutz2]

Do you just use the stuff from hardware store? Are you concerned about the fibers getting into the air with all the vibration?

I've normally just covered the fiberglass insulation using fiberglass window screen to avoid stray fibres

[retox]

I've normally just covered the fiberglass insulation using fiberglass window screen to avoid stray fibres


thanks, really good idea, was thinking about putting screen over the port on the inside.

[retox]

I've made some progress on one speaker. I need to complete the finish coat and attach the riser.
I was wondering what speaker cloth most of you use. Not sure what color I want yet, but would like to do some informed research.

85371

[nedseg]

Very Nice!!

Foam grills, very exact reproductions for the original look, they mount on ordinary window screens:

https://www.ebay.com/itm/JBL-L200-REPLACEMENT-FOAM-GRILLES-PAIR-ORIGINAL-CRENELEX-DESIGN/293227104844?hash=item4445b28a4c:g:ecYAAOSw53NY-4~Y

or
https://www.ebay.com/itm/Two-New-JBL-L-200-or-L-200B-Studio-Monitor-Grilles-With-Out-JBL-Badges/162462445844?hash=item25d3843114:g:VQ4AAOxyUrZSviE q

[retox]

I looked over the suggested grills and decided to make my own, but thanks for the suggestion it really helped with my choice in color and style. I ordered the badges this morning.
I am also looking at the repop lenses but wanted to know if they make an improvement to the sound especially in a small room.

https://www.ebay.com/itm/JBL-2308-L91-Style-KENRICK-SOUND-brand-new-Lenses-Perfect-Reproduction/253424107263?epid=1331878027&hash=item3b0140feff:g:RAEAAMXQdm5Q9T~T

My listening room is approx. 12 x 12 with 8 foot ceiling. I will be using one of the following configurations:

Marantz PM-17
Marantz PM-7005
Dynaco PAS 3 with Dynaco ST 70

My source is an Empire 208 with Jelco 370H tonearm, or AR XA with Grace 707 Tonearm
and a Marantz CD 6008.

I know these speaker are very large but I normally listen around 80db. I listen to acoustic rock and blues, some jazz, and some pop.

Thanks

-retox

85403

[Mr. Widget]

That’s quite a transformation, congratulations!

I suggest you get the lenses. The Kenrick Sound reproduction lenses are excellent quality and the H91 horns were never meant to be used without an appropriate acoustic lens.


Widget

[retox]

Thanks Mr Widget, I will get a letter out to Santa ASAP...

[retox]

I haven't finished yet but i am far enough along to move them indoors. I am currently listening to Donald Fagen Morph the Cat driven by a Marantz PM-17 and a Marantz PMD 320 CD player. Having some real fun...

85537

[retox]

85537[/QUOTE]


They are original L91 lenses that appeared to be in mint condition. Should I just use Velcro to attached the lenses or is there a way to attached with screws. I can add press fit nuts and use a machine screws for easy removal or I can attach Velcro to the cabinet. Also, I have seen the lenses pointed up and down, what is the difference or should they always be pointed down?

Thanks for all the help...

[Mr. Widget]

If you have the very early version of the L91 it has tabs for screw attachment, but most L91s are held on exclusively by using Velcro. When using the Velcro method, make sure you apply the strips carefully on the baffles with the finish cleaned and well cured.

When seating the L91s make sure you get a snug attachment. Many an L91 has fallen off due to sloppy attaching.


Widget

[retox]

If you have the very early version of the L91 it has tabs for screw attachment, but most L91s are held on exclusively by using Velcro. When using the Velcro method, make sure you apply the strips carefully on the baffles with the finish cleaned and well cured.

When seating the L91s make sure you get a snug attachment. Many an L91 has fallen off due to sloppy attaching.


Widget
I looked at the sellers photos and they appear to have the mounting flanges.
I may start with Velcro and migrate to fasteners. I have a few more details to complete. I have to build the side covers next. Really enjoying this restoration. Thanks for all the help Mr Widget.

retox

[laszlo]

A pleasure to see them transformed and brought to life again !!!
Congratulations on a beautiful piece of work !!!