Flat-face PT-F1010 waveguide with 1.5" 243X drivers works, too.
Here with 2435H, the HF could be padded down a bit (like 6 db!), or the system biamped to achieve the best balance.
Time alignment's better, probably, with this shallow horn.
[Ummm, "Crispy."]
What is the deal with the stripes?Originally Posted by Zilch
Grille kinda "floats." You can see back there behind it, so that part of the shiny aluminum frame is painted out....
You gonna do this?
I saw the hourglass shape of the cloth behind the grille and figured that it had shrunk over the years. I would not have thought it (A), it went out of the factory like that, & (B), that was the fix for it.
You've made a compelling case to do it that is for sure. When you look at it, you have to wonder why no one thought of it before? It makes complete sense. Kudos!You gonna do this?
My dilemma is modifying the factory casework. Granted, these are not JBL's best offering by a longshot and there is no big loss in doing so. However, it is one less set of original cabs. Also, I just have not thought through what I actually want these to end up as. I've got plenty to do while I figure it out though starting with the LE14A refoam and getting a better handle on the permutations of JBL HF offerings. I have a feeling once I get through that, I'll end-up asking you for the schematic of the final crossover iteration.
(I am actually going to bang through my L19A's 1st as they only need refoaming and I can have them up & running ASAP. Then onto the LE14A's, which look to be a real challenge.)
The answer to that is to get a pair of thrashed cabs from a nearby LE14A seller (so you don't have to pay freight,) for free.
You don't care if they have grilles or not. If they do, you can sell those on eBay to help pay for waveguides and compression drivers.
Use those cabs for "experimentation" before you commit to modify your own good ones....
You do have a way of boiling it right down.The answer to that is to get a pair of thrashed cabs from a nearby LE14A seller (so you don't have to pay freight,) for free.
You don't care if they have grilles or not. If they do, you can sell those on eBay to help pay for waveguides and compression drivers.
Use those cabs for "experimentation" before you commit to modify your own good ones....
That is an excellent suggestion.
John did it.
Thinkin' BEHIND the box again....
Hey, I'm new. Gimme a break!John did it.
Thinkin' BEHIND the box again....
I have a pair of cabinets originally made for LE-14A and LE-20 and if I can squeeze a 2226 in them and still use the port(with mods), would be interesting to see what it ends up like.
I would use a wood horn on top (rectangular 650hz tractix/Martinelli) and see how she does.
Thanks for all the great ideas guys!!!!!
Ron
If there is someone who lives within driving distance of Santa Rosa and wants to put this advice into use, I happen to have a set of badly abused L-55 cabinets available. Actually, they don't look too bad from the front. Send a PM, then come get em.The answer to that is to get a pair of thrashed cabs from a nearby LE14A seller (so you don't have to pay freight,) for free.
You don't care if they have grilles or not. If they do, you can sell those on eBay to help pay for waveguides and compression drivers.
Use those cabs for "experimentation" before you commit to modify your own good ones....
At 2+ cuft, the C56/L101 floor models can be easily retuned to BB6P's suggested optimum "Hi-Fi" alignment (30-32 Hz) for the LE14 family.
Kinda low-standing for integrating a horn into them; sittin' on top may be the best choice.
There was a less expensiver version without the marble, too. I forget the model number.
Any of those cabinets would be well worth rescuing from LE14A sellers for DIY, as well.
If experience to date holds true, LE175 in some of 'em will play nice with PT waveguides, adapters required....
[Hafta try that, too....
Remains after surgery. Note that JBL used masking tape to "fit" the cardboard ports into the baffles.
RTA shows performance with 2431H on PT-F1010 waveguide. Flatter than 2435HPL on this crossover, but they'll still require padding down for better balance with LE14A.
HF only on axis (bottom). This combo is "scandalous."
Boxes in Arizona here: http://cgi.ebay.com/VINTAGE-JBL-LANC...QQcmdZViewItem
1) 2-3/8" hole saw cuts ports for two 2" internal diameter ABS ducts in rear of S99 cabinet. Two wraps of masking tape will snug 'em up 'til I can check the tuning before final installation with, ummmm, I don't know what with. RTV or structural adhesive, probably. Something gooey.
2) View inside shows ducts clearing the front baffle by 1.75". Paired 8" ducts tune these boxes to 35.5 Hz, f3=53.9 Hz. I'll have to add some insulation and gain virtual volume to achieve that. Rear mounting of ducts makes that less of a problem; more insulation at rear won't block the ducts. I'll wrap whatever portion of them doesn't get buried, as well.
3) View from the rear shows ports. I reversed the T-nuts on the crossover cutout to mount a plywood block from the outside, with foam gasket to let the driver leads exit there and still make a good seal.
4) RTA at 12" shows actual LE14A performance. Get OUTTA HERE!
Compare to BB6P target design posted earlier:
http://audioheritage.org/vbulletin/s...page=2&p=74080
Thanks again, Johnaec for this great DIY upgrade idea....
1) LE14H-3 with 4" added fill
2) Same with 6" added fill
The big difference I hear with the fill is that all "boxiness" in the bass is gone. Apparently there were standing waves to absorb.
3) Well, economically, they're just silly:
LE14H-3 $400
2431H $800
PT Waveguides $170
Crossovers $200
Boxes free
Total $1570/pair, list, to build.
Consider, however, that the drivers are from Project Array.
[Less tweeter, of course.
Sound good, tho....
Even with the fill, they seem about 12db down at 40 hz. They could surely handle EQ down there, but it looks like the LE14 series just wants more volume...
John
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