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View Full Version : L-150 Mod Completed



Regis
07-19-2004, 04:06 PM
With all this talk about the L-150, I'm going to show what I've done to mine. Nice to see Johntherev who scored the pair and has them running. They are nice speakers stock, but I can't leave well enough alone, so I went down the path of mo' money and made them into what I wanted them to be.

As always, this site has been a tremendous help and support. There is no AA for JBL-itis. You catch it and it's hard to get rid of. You start to know what a 128H is, and what the different LE5 variants are all about. Good stuff for JBL junkies (like us!).

Here are the mods. I replaced the 128H woofers with the 2214H and now suffer from bruises and contusions. The cops ask me if I want to file a report or not. The walls literally shake and the couch gets a serious thumping. Yet it's still sharp and crisp with no muddiness whatsoever. No EQ needed here.

I replaced the LE5-10's with the LE5-9's. The 9's have higher efficiency and filled the gap in the midrange nicely. The powerful woofers tended to diminish the way the mids sounded and switching them out, really helped. The dB jumped from 91 to 94 db

Sir Giskard was super helpful with the crossover question and I replaced the stock crossover with a close variant of the 3113B. I found a very nice pair of L-112 crossovers on Ebay and these are beautifully built. To match the 3113B 16.5 uf value, I had to solder a 3 uf Sonicap in parallel to the 13 uf C1. The caps weren't cheap at $12 apeice, but what cost quality?

First, I did this with one speaker only, as I wanted to "A-B" the combination and see what the un-mod'd L-150 sounded like, versus the L-150 I just mod'd. It was exactly as you said it would be. The difference was incredibly obvious. The 3113b X-over had much more clarity and detail than the other speaker. The presence was fully there, instead of the old "dip" in the mid-range area.

Also the bass was much more unrestrained and seemed to flow much easier out of the speaker than before. The other speaker sounded like someone draped a wet army blanket over the front of the grill. Muddy mids, boomy bass and a sound that sounded like it was working hard just to get there. When I modified the other L-150, it was just incredible.

The pair had an easy power to them that I've never heard out of any L-150. The 2214H's worked effortlessly, the bass shimmering off as if the speaker was shrugging that kind of power with no sweat. The details really came out in the midrange area and the highs were excellent without ever sounding shrill. I've heard the bigger JBL's, having owned a pair of 4628's, but for a non 43xx or 44xx speaker, these have to be the best sounding JBL's I've ever heard. Even better than my old L-65A's and no EQ!.

Now to figure out how to mount the X-overs permanently and what filling to use to patch that big hole in the acoustical stuffing that removing the giant old X-over will obviously leave. Thanks for all your help on this, as I'm very happy with the performance of my speakers! It's really hard to get the grin off my face when I'm listening to them.

Regis
07-19-2004, 04:07 PM
The little one!

Regis
07-19-2004, 04:08 PM
Got it laying in the bottom of the speaker till I can figure out how to mount it correctly....

Regis
07-19-2004, 04:09 PM
Showing the Sonicap in parallel...

4313B
07-19-2004, 04:27 PM
Nice!

:cheers:

boputnam
07-19-2004, 05:47 PM
Regis...

Great job, for sure. Best part was you description of the process - 'specially getting to know the LE5-family. Your A/B test is one of the more true, objective A/B tests here. Too often, we get caught-up in our project, and don't capture the moment of being half-way and miss testing the outcome against the starting point.

Nice...

jontherev
07-21-2004, 09:09 AM
Ok, I could be jealous, but instead I'm intrigued. I might try something like this someday, but for now I'm happy with what I have. I might have to replace my mid's someday because several years ago, some candlewax dripped all over my speakers and a little bit got on the cones. It came off fine, but I wonder if it might make the cones deteriorate quicker. In any case, thanks for the interesting details of your project. Now, if that darn 033 would arrive, I could enjoy some balanced sound for once.:bomb:

Regis
07-21-2004, 09:25 AM
will make a big difference once you get it. I had an 033 that was inoperative when I first got the speakers and it was surprising how much was lost out of that one speaker!

Enjoy them for what they are, great speakers, but what you could do is slowly pull the parts together to mod this speaker, as you will find the results nothing short of unbelievable!

The 2214H's are really just incredible! I was listening to them last night and you could actually feel them, even at half a watt of power! The LE5-9's were well worth it too, as they filled a gap in the midrange.

PS: Bo, thanks for the feedback. Yes, it's tough to stop halfway through a mod and A/B the results, because you just want to get to the quickest point of flicking the "on" switch on the amp!

Also, Giskard has been tremendously helpful! Thanks!