L100T vs L100T3

[Blaster]

I have a pair L100T and a pair of L100t3. They are both the same height. The L100T are gloss black and measure 13 1/2" deep X 16" wide X 35 3/8" tall. The L100T3 are walnut and measure 13" deep X 14 1/2" wide X 35 3/8" tall. I don't have any L100S cabs to compare.

[pos]

Considering the difference in cabinet size (and especially the width of the front baffle), do you think it is a good idea to upgrade a L100T crossover to the L100T3 specs?
I mean, if the baffe is norrower on the T3 then the crossover has to be different to take the baffle step into account.
Does anyone has direct experience with doing this?

Also, has anyone mesured the DCR of the selfs of the T3?


http://manuals.harman.com/JBL/HOM/Te...L100t%20ts.pdf
http://manuals.harman.com/JBL/HOM/Te...100t3%20ts.pdf

[duaneage]

I don't think any cabinet variations would be that much of a concern. The big difference is the efficiency of the two drivers and the crossover from the mid to the woofer. The distance between them would affect it more.

I modified a set of crossovers for Evans224 a few weeks ago and tested them in my set. The midrange has different presence and the balance is smoother. In a different room with various source material it becomes a matter of choice.

I can modify a set for someone else if interested, I have extra parts and a spare set of crossovers to perform exchange with.

[hjames]

Just got back from picking up a pair of L100T -
seller is headed out of town and just wanted to get rid of them - (stereo shown not included in sale)
of course, the woofer surrounds are gone ... but the price was nice

They look to be REALLY clean - but - I had no idea these things were so darned HUGE!
(what do I know, I've had L20T and L60Ts in the past)

Anyway I just got them home and need to head to bed -
but I'll post more specifics tomorrow once I get into them them and get specifics of the drivers and crossovers and such!

[opimax]

good deal, look good from the pictures. what are you going to do with them?

Mark

[hjames]

good deal, look good from the pictures. what are you going to do with them?

Mark

Get them working first (refoam), then possibly upgrade the crossover, smooth them out ... Afterwards - not sure yet ??

They have rear-firing ports, and I know how to cure that, but they are too big for the TV room,
and redundant upstairs with the L200 3ways ...

But at least they aren't L5s ... all that Black ash - yeesh!

(just kidding guys, relax!)


Why?

[opimax]

Inquiring munds want to know, nothing else! Really!

I would like to hear them sometime, after all they are JBL

Mark

[hjames]

Inquiring munds want to know, nothing else! Really!

I would like to hear them sometime, after all they are JBL

Mark

Well, I put this pix in another thread but - darned - these puppies are larger than I had imagined from the pictures ...
In those pix they kinda looked cute, like the L20T - but when we got there and checked them out -
wow, they are 3 foot tall! Look at them next to my L200!
Rock'n'Roll indeed (where's that Tempest CD??)

I'll have to build some wheeled bases for them like I did for the L200s and 4341s.
I ordered a Rick Cobb 2214H foam kit early yesterday!
Busy weekend coming up, but maybe I'll get to them by the 9th
( I still have to find time to get the H92 long-horns into the L200s,
and get the aquaplassed 2425 drivers into the 4341s!!)
But its summertime - big speaker work can wait for either the dog days of summer, or for the winter!

[bigyank]

Well, I put this pix in another thread but - darned - these puppies are larger than I had imagined from the pictures ...
In those pix they kinda looked cute, like the L20T - but when we got there and checked them out -
wow, they are 3 foot tall! Look at them next to my L200!
Rock'n'Roll indeed (where's that Tempest CD??)

I'll have to build some wheeled bases for them like I did for the L200s and 4341s.
I ordered a Rick Cobb 2212H foam kit early yesterday!
Busy weekend coming up, but maybe I'll get to them by the 9th
(and I still have to find time to get the H92 long-horns into the L200s!)

I hope you meant to type 2214H Heather! I always liked the bass from these woofers but personally never thought the rest of the system could keep up!

[hjames]

I hope you meant to type 2214H Heather! I always liked the bass from these woofers but personally never thought the rest of the system could keep up!

yep - early AM slippery fingers ...
Checked the order and 2214H it is!

[evans224]

The L100T's work great in my HT setup. Like Bigyank said, the 2214H's are impressive. I was not happy with the rest of the system either. After Duanage modified the x-overs, the mids backed out of my face a bit and the highs lost that really sharp edge. However, the best thing for them was to get them out of the hard-surfaced room they were in. By the way, here are some before and after pics here-I finally got around to finishing them. Yours are in much better shape than mine were.

[bigstereo]

Congrats Heather. I've been loving a pair of L100t3's for the past 3 years.

Bet you wish you had a spare set of 035TiA's laying around now eh? Just in case.

RJ

[hjames]

Congrats Heather. I've been loving a pair of L100t3's for the past 3 years.

Bet you wish you had a spare set of 035TiA's laying around now eh? Just in case.

RJ

Yeah, why oh why did I ship them t'ings to NY??

Funny thing is - when I arrived at the sellers house he started to play them for me with some kind of thumpy rock music - even with the blasted foams.

I had him turn them off quickly, but it did sound like there mids and highs present ... I'd hate to gut my L20Ts to get these things working!

So, maybe next weekend after I get the refoams installed I'll have some idea of what I've gotten.

My living room is a fright now anyway, with these big things next to the L200s, a pair of H82 long horns on the coffee table, and next to those a clean pair of 2425Hs with fresh aquaplas ti diaphrams ...
I ought to be able to get some good sounds going with all of that laying around!

[pierce]

I'm curious about the differences in the crossovers, i started a thread elsewhere in this forum w/ the schematics of the L100T and T3 crossovers, both speakers claim 800Hz and 4500Hz crossover points and 12db/octave. I can see the two circuits are the same topology but have somewhat different component values but don't remember enough of my college electronics to be able to say what that means.

Also, interesting, looking at these two wiring diagrams, it -appears- if the L100T and T3 have all three speakers reversed in phase relative to each other...

http://manuals.harman.com/JBL/HOM/Te...L100t%20ts.pdf
http://manuals.harman.com/JBL/HOM/Te...100t3%20ts.pdf

[duaneage]

The phase reversal has to do with the type of network and how the filters sum at the crossover point. Without reversing the phase there would be a hole or peak in response at crossover. These are typical 2nd order networks that sum flat electrically at the crossover point only if the middle driver is out of phase.

The midrange and woofer interact above and below the crossover point. No crossover frequency is a hard value, there is content from both drivers above and beyond the frequency. The difference is how the polar response works along with the level of each driver. Subtle changes in the crossover components can have marked results and usually do not agree with calculated values. Many of JBL's designs violate rules for crossovers but that is because they leverage the natural response of the drivers. Many times the designer goes for a typical "sound" versus an absolute flat response.

THe T3 circuit also dampens the high frequency to soften the tweeter response. Metal domes can be a bit harsh so this is an improvement. The midrange is where the music is anyway so the tweeter augments the midrange without overpowering it.

Essentially what the T3 network does is create a "hole" in the transistion between the woofer and midrange by lowering slightly the woofer's crossover point and raising the midrange crossover point while still being centered on 800 hz. . The 2214H has a rise in response above 1.2 Khz so this reduces that peak. The midrange is raised a little and that isolates it a bit from the woofer while tweaking the loudness slightly.

The result is a bit smoother midrange, less shrill highs, and the bass seems clearer. With some tweaking other JBL designs could be helped this way too but we have a production standard that can be duplicated which has the blessing of the JBL design engineers.

There is a host of other things going on too like driver spacing, time alignments, impedance, phase response, edge diffraction, and temperature changes too but in the end the T3 network is a bit nicer to listen to and that is all that matters.