Frankenspeaker?

[bigstereo]

Some of you all may think this is a dumb question but here it is any ways.

What if one were to take all the components from a pair L100 Century or 4311 and put them into a bigger cabs, say 5 cu ft, non ported? Or if it would be better, ported.

[Thom]

It would be interesting. The D123 that the woofer is based on was designed for a smaller cabinet, but smaller probably ment at least as large as your speaking of. It was designed with base reflex in mind but by that they ment a decent sized hole or a hole with a shelf on the edge that is toward the woofer.However,that was before they plastered it all up and out an accordion surround on it which is a pretty major mod. I've been going to try somthing like that some day but I haven't even gotten around to procrastinating yet.

[Zilch]

http://audioheritage.org/vbulletin/showthread.php?p=123561#post123561

I'm now thinking 104H-2 for the midrange rather than fighting LE-5 with the crossover.

It's a "closed-box" woofer. EBP = 48

That makes a closed-box L100t3

http://manuals.harman.com/JBL/HOM/Technical%20Sheet/L100t3%20ts.pdf

Who's got T/S parameters for 123A-1?

BB6P has different than what JBL has published for the 2213s

Edge says 123A-1 is 2212, which is not in the database.

I THINK the forum has been through this before, but I am unable to find it.... :dont-know

[Robh3606]

It sounds just like the Alpha JBL did but they used a pasive radiator and the Le-20 so it was closer to the 4310 look here:

http://www.lansingheritage.org/images/jbl/catalogs/1969-home/page10.jpg

Actually has some promise as your woofers do better in a larger box. Have fun!!

Rob:)

[spkrman57]

http://audioheritage.org/vbulletin/showthread.php?t=4961&highlight=wt2

Ron

[Zilch]

Thanks, Ron.

Your Vas translates to 212.4 L, i.e., closer to the 124A spec.

Guess I'll hafta rip the insulation out of an L88 and measure a bunch here.

Getting the Vas right is critical to deciding on a box design.... :(

WinISD shows 123A parameters for the 2213s.

[Robh3606]

WinISD shows 123A parameters for the 2213s

Hello Zilch

It should?? They are the same:hmm: Huh!!! Learn something new every day check out the Tech Sheet for the L88 Plus and the driver interchangability.

http://manuals.harman.com/JBL/HOM/Technical%20Sheet/L88%20Plus%20ts.pdf

Look at this old Pro Note publication. Look at the recomended box.

I have 4 123A-1's Two came out of my L88's and 2 are Ebayed


Rob:)

[Zilch]

Thanks, Rob! :thmbsup:

Edge says 2213 is 123A-3, 2212 is 123A-1

There's no tech sheet for 4310, apparently.

We now have an argument for 4311 being "better" than L100!! :applaud:

BB6P returns inordinately large boxes for vented alignments.

But nice-sized ones for closed box, which I'm positing is preferred.

Thinking "Baron," for example, 3 cuft. :)

If I was building (the subject of this thread,) I'd go right for L100t/t3 (they're different) dimensions, ~3.3 cuft., and driver layout.

[Robh3606]

Hello Zilch

Yes I was thinking along the same lines just keep the box sealed and not use the PR. He can always adjust the box size as required. If he already has the drivers here's the Tech Sheet for the Alpha:

http://manuals.harman.com/JBL/HOM/Technical%20Sheet/S70%20Alpha%20III%20ts.pdf

Rob:)

[bigstereo]

I was thinking of using a Bozak 302a French Provincial cab, if I don't like the sound of the Bozaks in them.

[Zilch]

Assuming 5.0 cuft., and employing 124A parameters, it's too large for closed-box alignment. You run out of cone excursion at a relatively high frequency (35.11 Hz, top, red).

Tuning to 26 Hz with 1 x 4" x 6.44" long port, you're good to 20.54 Hz (-10 dB, bottom, black), where it's also displacement limited. It'll retain L100's boomy bass, but play lower. Use an infrasonic (highpass, aka subsonic, aka rumble) filter at 20 Hz to protect the drivers:

[spkrman57]

Sounds like something I want to try in the near future.

Great thread, there's some info I can use here!

Just have to pick the mid/tweets and crossover to go with it.

Thanks, Ron

[Zilch]

Sounds like something I want to try in the near future.Yup, they worked in the closed-port L88s pretty good, so I'm gonna drag some Barons up from the dungeon to try. You can bet I'll jump on the next "distressed" L100t/t3 I encounter, too. :p


Just have to pick the mid/tweets and crossover to go with it.Easy. 2452H-SL on PT waveguide, NL200t3.

O.K., O.K., BMS 4552nd on the JBL $10 waveguide, then, 3120A to start.... ;)

[Zilch]

Viscounts, instead. Better for stacking horns on top. :p

Gotta make baffle adapters; these are cut for a single 15".

Alas, no stilettos, but these inverted obelisks aren't bad looking in person.

[If they work, they'll look even better in JBL Monitor Blue.... :) ]

[Robh3606]

Hello Zilch

Sure you have enough speakers there??

Rob:D

[Zilch]

Heh, heh. "Research!"

A plethora of plumbers' plugs in evidence! :p

[Robh3606]

A plethora of plumbers' plugs

You should add that to your quotes:applaud:

Can you say it 3 times fast????

Rob:eek:

[Zilch]

by comparison:

[Zilch]

You should add that to your quotes:applaud:Done. :thmbsup:

[Robh3606]

WOW :eek:

Who's pile of goods is that!!

Rob:)

[Zilch]

That's a friend's dungeon. He's a "Hornie." :p

Turned out I didn't have any Barons in mine, but he had several pair.

For my purposes, testing two-way with horns, these Viscounts I found there are better.

If these work, I'll try some Barons with asymmetric waveguides, like stage monitors, to overcome the limitations of their "lowboy" configuration.

The front baffles are removeable, so just about any driver combination can be installed in them using a custom baffle, as required. The box frames on these are lock-mitred, so they're quite stable with both front and back removed.

It'll take some extra effort to achieve a tight seal on the front, tho; it was not so critical an issue in the original ported design. I haven't worked that part out yet....

[Robh3606]

Here try this

http://www.partsexpress.com/pe/pshowdetl.cfm?&PartNumber=260-540&DID=7&raid=44&rak=260-540

Rob:)

[Zilch]

Thanks, Rob.

The problem is sealing through the grille cloth, which wraps around the edge of the front baffle.

That foam tape may well work, since it "squashes" conformally....

[spkrman57]

Zilch,

I have found closed box systems to much more tolerant of tuning. Even if you are off 10 hz one direction or another the resultant product will sound pretty much similiar.

Vented boxes require much more precision to meet the end goal requirements.

Just my 2 cents worth for what its worth!:blah:

Ron




Thanks, Ron.

Your Vas translates to 212.4 L, i.e., closer to the 124A spec.

Guess I'll hafta rip the insulation out of an L88 and measure a bunch here.

Getting the Vas right is critical to deciding on a box design.... :(

WinISD shows 123A parameters for the 2213s.

[Zilch]

Thanks, Ron.

It's clear what happens as we increase the closed-box size with 123A from 1.6 cuft. L88 or L100 (green) to 2.0 cuft. L55 (blue) to 3.0 cuft. Baron (red) to 5.0 cuft. whatever (black).

Xmax is 7.874 mm., so 3.0, or 3.3 cuft., even, is likely "safe."

[spkrman57]

I think my L55 cabinets are ready for my 123A-1's!;)

The LE14H-1's will go into the 250 cabinets.

I only have to make one panel(front baffle) with cutout for the 12" and use a 800hz crossover to one of my Edgarhorns. I love the round tractix horns for their "non-hornlike" sound characteristic.

I will have to run a impedance curve on my WT2 for crossover design with the 123A-1.

I will also have to try out a 1st order crossover with a 20% frequency split at 1300hz also. (Just a hunch I have from a similiar experiment in the past).

With our buddy Giskard inactive lately, it is nice to see you and others taking the ball and running with it!:applaud:

Regards, Ron

[Zilch]

It's likely Giskard has tried this stuff before, like 2213H in closed EN3, for example.

I'm confident that if I suggest something REALLY stupid, he'll be so overcome with incensement as to reappear here for no other purpose than to kick my ass, in which case, as concomitant benefit, we'll get some good advice.... :p

[spkrman57]

Giskard has tired of the grief by some of the members here and will likely just lurk around for the most part. I am fortunate that he still answers my e-mails.

And for those who question the DD66000 system, Giskard commented to me he did not turn on his own system for 2 weeks after hearing the Everest in person. That is testimonial enough for me!;)

Ron



It's likely Giskard has tried this stuff before, like 2213H in closed EN3, for example.

I'm confident that if I suggest something REALLY stupid, he'll be so overcome with incensement as to reappear here for no other purpose than to kick my ass, in which case, as concomitant benefit, we'll get some good advice.... :p