JBL L100T, Restoring and Upgrading!

[ramin_audio]

Yes the cabinets are different sizes and the crossovers are different as well.

Rob

The T version should have a larger cabinet -- right?

[ramin_audio]

I also want to brace the cabs when they are back at my house. Can somebody kindly introduce me some threads and/or websites that give instructions. If there is a thread that specifically talks about bracing L100T cabinets, it would be wonderful.

I really appreciate any help.

[hjames]

I also want to brace the cabs when they are back at my house. Can somebody kindly introduce me some threads and/or websites that give instructions. If there is a thread that specifically talks about bracing L100T cabinets, it would be wonderful.

I really appreciate any help.

Do they really need bracing?
I know a couple of us that own the L100T and have not braced them ...
The big upgrade is getting the 100T crossover upgraded to the T3 specification.

[berf]

In terms of gross dimensions the T3's are actually a little smaller. Same height, 1/4" deeper, but 1 1/2" narrower. The T's weigh 77 lbs, the T3's are 58, that seems to tell me the T3's use a thinner cabinet material also. Possibly the internal volume is similar, someday I'll measure and calculate it. Somewhere I remember reading that the redesign made for less waste of "veneer" (sorry but I'm not a fan of the T3's wood product covering). I have both cabinets, side by side they look very different, primarily because the T3's have a taller grille. I prefer the proportions of the T's.
You can add bracing all you want but you'll be decreasing internal volume and see little benefit. If you had T3's I'd say maybe but for T's it's a meh.

[ramin_audio]

Do they really need bracing?
I know a couple of us that own the L100T and have not braced them ...
The big upgrade is getting the 100T crossover upgraded to the T3 specification.

Mine would have a better xo than both of the T and T3 xo's, with quality L-pads. I hope I am making a super-L100T.

I have to think about the bracing though.

Thanks.

[ramin_audio]

In terms of gross dimensions the T3's are actually a little smaller. Same height, 1/4" deeper, but 1 1/2" narrower.

According to hjames,

L100T3: 35 3/8" tall x 14 1/2" wide x 13" ..... deep

L100T:. 35 1/2" tall x 16" ..... wide x 13 1/4" deep (base adds 1" height)

http://www.audioheritage.org/vbullet...l=1#post251062

I measured the depth myself and it was 13 1/4". So, L100T is deeper too, and 2 1.2" wider. The internal volume maybe similar though.

The T's weigh 77 lbs, the T3's are 58, that seems to tell me the T3's use a thinner cabinet material also.

That's cool.

You can add bracing all you want but you'll be decreasing internal volume and see little benefit. If you had T3's I'd say maybe but for T's it's a meh.

I'll consider that too. I may go for some minimal bracing. I have to find out the most efficient ways to do that.

[lgvenable]

As others have said, I agree when you own L100's>>your money is best spent on upgrading the crossovers.

On refinishing do a search and you'll find some suggestions for fixing scratches etc under my username. Namely fill voids, chips, or scratches with walnut dust wood putty, and then use Watco danish (walnut in my case) oil to wipe on and finish to the JBL OEM finish.

If needed you can use a #2 pencil to draw in grain lines on the filled areas, and with careful use of watco you can make a filled arera look identical to the surrounding spagetti wood veneer. All of mine were in walnut, and I had them all upgraded to T3's before I ended up going to a three way setup with individual amps for each driver (and selling my L100T's).

Why brace?? JBL did a fine job designing them, spend your money upgrading the x-overs for a real smile. :<))
Larry

[pathfindermwd]

The internal volume maybe similar though.

I have the T and the L100S which is the T3 service version with vinyl veneer. It should be the same dimension as the T3 and as Heathers measurements suggest, it's smaller (inside and out). I remember measuring them both at one time and they are both made with 3/4" particle board. I am not sure about it weighing only 58 pounds though, the things are heavy now, they seem just as heavy as the T. The T3 seems to do better on a knuckle test than the bigger T. The T3 has a larger diameter port.

All of mine were in walnut, and I had them all upgraded to T3's before I ended up going to a three way setup with individual amps for each driver (and selling my L100T's).

Larry that is very interesting. I have thought about doing this as well. Not only would individual amps be killer, but a powered L100T3 would be novel. Did you post this transformation? do you still have them? How do they sound?

[berf]

Looking at the various shipping weights between the T's, T3's, and 44 series there are similar discrepancies. Without weighing things myself I'd say the T-series stated shipping weights are on the high side and the T3 weights are on the low side.
I just weighed a 4410 and it was 40 lbs. The shipping weight is 50 lbs and I doubt if there was 10 lbs of foam and cardboard in the packaging. If someone wants to throw a 100T and a 100T3 on the scale we'll have some numbers based in reality to work with.

[JBL Eardrums]

I think the L100T cabs made out of the old school (large splinter, loose density) particle board, but a difference I noticed glancing at a L100T3 - it seemed the front baffle was actually made of MDF, perhaps the rest of the cab made of a cheaper particle board with a MDF front baffle? This would not explain the weight difference though. L100T also has a particle board "riser" ... T3 might have a plastic riser, but that is only good for a pound or so. Some of the "T3 Upgrade" concerns about internal bracing (added to an L100T) would seem appropriate if the T3 has an MDF baffle. I love my L100T's, but I really love the difference in the T3's smoother sound.

[ramin_audio]

I am going to improve the cabinet by doing some smart bracing... I don't think there would be volume problem to what I am going to do.

I believe they would sound really decent with the newly designed xo and new insulation materials and some bracing and I am gonna stand them on spikes. ...

I really love my JBL 4312A with new xo. The mids and highs are really good... L100T has the same tweeter and very similar midrange.
I am just curious about the woofer. I hope they are good enough for me.

[pathfindermwd]

I am going to improve the cabinet by doing some smart bracing... I don't think there would be volume problem to what I am going to do.

I believe they would sound really decent with the newly designed xo and new insulation materials and some bracing and I am gonna stand them on spikes. ...

I really love my JBL 4312A with new xo. The mids and highs are really good... L100T has the same tweeter and very similar midrange.
I am just curious about the woofer. I hope they are good enough for me.

Only you will be able to decide. They are an excellent woofer in my opinion. Look up the 2214, there is a chart that compares them the the LE14H-1 somewhere around here.

We have discussed L100T upgrades quite a few times. These were some of the suggestions: make new cabinets that are mirror imaged, with rounded front corners, out of 1" MDF (or better), and with the T3 crossover, or better a Charged Coupled Network, or a bi-amped network, put the ports in the front to ease placement.

[ramin_audio]

Only you will be able to decide. They are an excellent woofer in my opinion. Look up the 2214, there is a chart that compares them the the LE14H-1 somewhere around here.

We have discussed L100T upgrades quite a few times. These were some of the suggestions: make new cabinets that are mirror imaged, with rounded front corners, out of 1" MDF (or better), and with the T3 crossover, or better a Charged Coupled Network, or a bi-amped network, put the ports in the front to ease placement.

1" MDF! Sounds cool!

Frank Fabian is making new xo for them with his top-quality components (Max Fidelity). I think it be will be better than both T and T3 xo's.

Making the front baffle, esp. the circles for the drivers must be very hard. How am I be able to make them?
Is there a thread that helps?

[hjames]

1" MDF! Sounds cool!

Frank Fabian is making new xo for them with his top-quality components (Max Fidelity). I think it be will be better than both T and T3 xo's.

Making the front baffle, esp. the circles for the drivers must be very hard. How am I be able to make them?
Is there a thread that helps?

There are jigs available from place like Parts Express to cut large circles for such drivers ...
I am NOT the wood working guru - my tools are simple and I generally buy the cabinets I need -
but I gather you can use a router to put a bullnose on the edge of a cabinet if the wood has sufficient depth to work.

I have seen some of the more skilled cabinet gurus here making more complex designs -
but I wouldn't begin to explain their toolings ...!

[ramin_audio]

There are jigs available from place like Parts Express to cut large circles for such drivers ...

How about the volume? What are the best dimensions?

How do I make round edges?