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Technical documentation for JBL L100 Classic Tweeter (JT025TI1-4)

Thank you for the updates.. it’s really appreciated..!
Well.. how about that..?
So…. stock Xovers, drop in ..and bingo..! And an improvement in over all sound.. to boot..
Any pics..? Would love to see the finished product..
The 4412a are supposedly a near-field listening monitor, and I suspect you’ve turned them more into a normal distance listening loud speaker..
No need to spend $4k on the L100 Classic, when this option is available…
How do you position your speakers..? Horizontally or Vertically..?
 
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I think they look pretty good! I normally have the grills on, though. As you see they're in horizontal orientation with the tweeters on the inside, as god intended haha

I know JBL said they can be used near field, but I always felt they're best from 1.5 to 2.5 meters away.

You can really use them with the stock crossovers, BUT I would highly recommend to upgrade those crossovers, if you can or know someone who can.

My "upgrade" is a bit overkill, but I did two pairs at a time and got a cheap PCB and parts supplier thanks to the university I work at. That bigger PCB let me use high grade industrial components (no "audiophile" parts here, just really good, state of the art parts) and not a single electrolytic capacitor. The circuit is basically the same as the original (corrected a small error in the woofer/mid crossover point), but since it looks like they modelled it with "ideal" parts, this version is probably way closer to what the engineers intended.

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I know it's a cliché, but with that new crossover this is basically a brand new speaker. What REALLY surprised me was the difference in bass performance. I replaced those crappy sand resistors with 30w foil resistors with heatsinks. It blows me away how these speakers sound now. I replaced everything except the inductors (they measured really well) with modern parts.

On the original PCB, if you can replace the power resistors in the woofer path and upgrade the electrolytics to modern audio grade types (the old ones in mine were already dying and drifted quite a bit) you will have a noticeable improvement for less than the price of one of those new tweeters.

Good luck with everything!
 
Wow.. those tweeters look like they came installed that way from the factory..! i wouldn’t be able to accept the 2mm height difference either…. So definitely will be installing then flush… Nice job on the X-overs… Thats very impressive.. ! Yes, I would absolutely perform the upgrades my self and thank you for the tips… Will definitely look into upgrading the components.. don’t know if I would be able to replace the whole X-over board as you have done(i don’t have access to the same resources as you), but will definitely will take your advise on what to upgrade.. I have never seen those types of capacitors that you are using before..? I’m assuming they are film caps..? I see the large one to the right is a Vishay, what are the others..? Also, curious to know what you corrected in the woofer/mid X-over point..?
Cheers..!
 
The caps are Panasonic and Vishay film caps (looks like they come from the same factory) for industrial applications. Phenomenal specs and they last for a thousand years. If you need big values to replace the electrolytic caps they tend to get huge...

I moved the XO-point down by about 40hz, solved the slight 780hz dip I had. If you want to do that I recommend that you use a simulation like LTspice with the actual measured values of the drivers and the exact specs of all the parts you're planning on using. And don't go too low with the mids, they're in a separate enclosure that's about 0.9 liters, below 600 hz it starts to get bad. It's all not really necessary though, they're very flat as is and a good EQ like in Roon or other good audio players can probably solve that small "problem" without all the hassle.
 
Update: The JT025TI1-4 tweeters have arrived and I measured and installed them. They are indeed a drop-in replacement for the old 052ti. They measure 96dB SPL/1W and around 4 Ohms DC resistance, like the 052ti. Luckily, they also fit the 4412a cabinet without modifications (apart from new screw holes). The terminals are also the same size, but it's of little use, since the polarity is flipped. You will have to account for that when installing.

I haven't listened yet, but I assume it's fine. In the process I have also confirmed that a properly working 052ti is a damn fine tweeter :)
Hi stumbled upon this thread in search of a replacement tweeter for my L82 classic. I have had no luck sourcing the JT025Ti1-4 tweeter. Wondering if you can share the supplier info from Germany that you purchased the tweeter from?
 
Hi stumbled upon this thread in search of a replacement tweeter for my L82 classic. I have had no luck sourcing the JT025Ti1-4 tweeter. Wondering if you can share the supplier info from Germany that you purchased the tweeter from?
They‘re called ESCoor (escoor.de)!
 
Yeah thanks for this information, ive also been searching high and low for replacement tweeters and was going to order made in China ones feom the US at a stupid cost!
 
Escoor.de wont deliver to the uk so its back to square one....
Hi. If you find a source that will ship to the UK please can you share? My out of warranty L100 classics have a leaky tweeter (ferrofluid): that unit measures more or less identical SPL with white & pink noise against the good one but I'd like to replace...
PXL_20230304_135805127.jpg
 
Hi. If you find a source that will ship to the UK please can you share? My out of warranty L100 classics have a leaky tweeter (ferrofluid): that unit measures more or less identical SPL with white & pink noise against the good one but I'd like to replace...

How long have you had them? The warranty is 5 years. Have they even been made for 5 years? JBL had a policy of replacing drivers gratis, even if after the warranty expired. That was when JBL was its own company. They probably wouldn't do that now, but who knows?
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Hi. If you find a source that will ship to the UK please can you share? My out of warranty L100 classics have a leaky tweeter (ferrofluid): that unit measures more or less identical SPL with white & pink noise against the good one but I'd like to replace…

3SPKT01HM100KT is the actual part number of the L82/L100 tweeter. Your countries JBL distributor/dealer should be able to source one for you.
 
I have a new pair of JBL 100 Classics that I bought as an open box special. Later I found out why. With one of the speakers the back half the tweeter, the magnet, was rolling around in the bottom of the cabinet. I removed the woofer to get to it and removed the tweeter. The magnet is quite powerful and went back in to place. There was a brown gunk that wiped off (maybe glue). Once reassembled the speaker sounds as good as the other one. JBL is sending me a new tweeter supposedly. My questions are: does this part really come apart? What was the brown stuff? Is the tweeter now repaired assuming there was no damage? The JBL techs didn’t know much about the design of the part. This group seems to know more than the guys that answered the service line phone.
 
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