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Daryl
01-24-2008, 02:26 PM
I'm thinking of buying a pair of Jbl L150 Speakers to compliment my other pair.The ones I'd like to buy have the following upgrades, upgraded Midranges with the LE5-9 .Replaced the 128H woofers with the 2214H woofers from the JBL L100T speakers,and modified cross-overs with bypass capacitors.Can anyone tell me what difference these modifications make and how good a upgrade from original these are?.Also is this a good modification. I'm told this work was done by a qaulified technician per JBL specifications on the JBL Lansing Audioheritage website.Any help or information anyone could provide would be greatly appreciated

grumpy
01-24-2008, 07:31 PM
OK, ... replacing the mid with an LE5-9 would likely change the voicing
audibly... whether this is an 'upgrade' or not is in the ear of the beholder.
The changes described don't appear to match what JBL has recommended
as replacements:

http://manuals.harman.com/JBL/HOM/Technical%20Sheet/L150%20ts.pdf

but whatever. If those L150's float your boat, then enjoy.

Seems like a nice upgrade path might be using L100t/L100t3 components
and network then re-weighting the passive radiator (if necessary).

Cheers, -grumpy

Chris Brown
01-25-2008, 08:39 PM
There are a few things to consider. First, the idea that such significant parts swapping can be done “per JBL specifications” is pretty laughable.

The LE5-9, if I recall correctly, was from a previous line of JBL’s with a different response curve. If you were going to put something in there that could be considered an “upgrade”, at least on a technical level, I would think you would have to go something like a 104H. I don’t really see what the point of having LE5-9’s in there is; I’d guess that’s what was available on eBay when the previous owner put them together.

The 2214H woofer diameter is physically larger than the 128H woofer by about half an inch, meaning that to fit a 2214H into a L150 cab you would have had to make permanent modifications to the cabinet, which in my opinion brings down the collector/vintage value of the speakers. The 2214H is also a deeper cone that iirc has more excursion than the 128H possibly causing issues with the PR300 passive radiator not being able to keep up.

I have L150s and L100Ts that I run together in my music setup, and I feel that they each bring something that the other lacks, so maybe these modified L150’s will sound good. Still, most of the parts swapping adventures I’ve come across seem to be where the owner got a good deal on some components then wonders “how will this sound if I stick it in there?” rather than any technical reason or if it will actually be an “upgrade” or not.

johnaec
01-26-2008, 06:55 AM
The LE5-9 is 3 dB more efficient than the original LE5-10, so you'd need to dial back the midrange level control for the closest match.

John

johnaec
01-26-2008, 08:35 AM
The 2214H woofer diameter is physically larger than the 128H woofer by about half an inch, meaning that to fit a 2214H into a L150 cab you would have had to make permanent modifications to the cabinet...Hmmm - I just compared a 2214H with an 126A, (I *think* it's the same dia. as a 128H), and it's not quite 1/8" larger, and *might* fit in place of the 128H. The screw mounting holes are exactly the same as all JBL 12's.

John

Chris Brown
01-26-2008, 11:57 AM
Hmmm - I just compared a 2214H with an 126A, (I *think* it's the same dia. as a 128H), and it's not quite 1/8" larger, and *might* fit in place of the 128H. The screw mounting holes are exactly the same as all JBL 12's.

John

http://audioheritage.org/vbulletin/showthread.php?t=4700

Here is a thread where someone did mods to L150’s as was described, in fact, it appears to be exactly as described; I wonder if that is the seller?


To fit the 2214H, you'll have to get a drill motor and a cylindrical sanding bit nd open up the woofer enclosure just a tiny bit. Move the drill around evenly in circles and test often. Mine are a friction fit. Make sure you get the polarity right