L200 Network Schematic...?

Sorry Robh (or whomever...) to come back to the well so quickly, but this mate of mine plans to run those L88's paired with some L200's he's refitting.

The L88 cabinet is factory positive. I need check the L200 network, same-same.

And, he's perplexed between the 136A, 2235H or LE15A. Here's a plot of all three in an approx. L200 cabinet.
136A = Green
2235H = Blue
LE15A = Yellow

I guess the 2235H would be safest, to avoid any chance of weakened alnico motor. Anybody run either of these in the L200 and have an good/bad experience?

Which L-200 are you working with?

The original L-200 with the LX-16 which crosses over at 1200Hz using the 4 ohm LE15B will not work well with any of those woofers.

If it is the L-200B then you can pretty much just drop in the 2235H and be in good shape. You may want to lower the box tuning a bit to extend the low end and reduce the JBL bass bump.

Thanks, Giskard and Mr. Widget.

Pretty sure it's the L200B - I'll check.

And, he's fitting in some 2482's and 075's (I suggested 2405's to no avail... ;) ).

I thought if he could find them, a great combo might be the LX5 and N7000. Anybody got schematics for them?

Does this make sonic sense? Alternatives come to mind?

Well here you go

200B

Thanks, heaps, Robh! Much appreciated.

If it is the L-200B then you can pretty much just drop in the 2235H and be in good shape. You may want to lower the box tuning a bit to extend the low end and reduce the JBL bass bump.

Re-reading friend's emails, I fear he's got the L200A - original with the LE15B. So, if he's going to drop in the 2235H's, what to do with the ports / tuning? Overall a bad idea, or what?

"And, he's fitting in some 2482's and 075's (I suggested 2405's to no avail... ).

I thought if he could find them, a great combo might be the LX5 and N7000. Anybody got schematics for them?"


Hmmm.... well if he is stuck on using that mid driver he will need a tweeter that can come in at say 5KHz so the 075 or 2404 are the ones if a JBL is to be used. In the JBL line up the N7000/3105 is the best bet, but not ideal. I assume he will be using the HL93/2311-2308 so a 500Hz crossover is a bit low for that horn. Yeah, it was originally called a 500Hz horn but they used to do a whole lotta wacky things! I would not use it at all but if you must I would not go below 1200Hz which kind of defeats the purpose of the 2482.

Here are the schematics for the 3105 (N7000) and 3115 (LX-5)

http://www.jblproservice.com/navigat...chematics.html

As far as the woofer is concerned that is the least of your worries. I don't remember the actual volume of the L-200, but I assume that it is about 5 cu ft. It is probably tuned to 35Hz give or take a few Hz. Calculate the actual volume and retune it to 29Hz if you are going to use the 2235H. It will probably be too long for the two ports of the L-200 so use one port and cap the other.

Have him build a super 4343 with a 2440 or 2441 instead of his 2482. Use the stock 3143 crossover and add a half cu. ft box on top with the 2121 in it. Or build a new cabinet.

Excellent, and thanks Mr. Widget for the lengthy discourse. It won us an experienced new member coming into the Forum - "thatguy" - so, he'll be carrying his own projects here.

Mr. Widget, having just read your great post about re-tuning the L200 cabinets, I was thinking that you have have an informed response to my question about my 4320 cabinets.
My 4320 cabinets came with the stock 2215 woofers. Each cabinet has two 4" ports that are 7 1/4" long. I've changed the woofers to 2231s and removed the mass rings, effectivly giving me 2234s. How should I adjust the ports to accomodate the woofer change?
My 4333s have aprox. the same 5.5 cu. ft. cabinets but use one 4" port that is 4 1/4" long. I changed the woofers in these 4333s to 2234Hs for better mids. What port length changes, if any, would you recommend for these 4333s?
It is an easy matter to insert plastic tubes inside the 4" tube to lengthen them if that is what's needed.

I guess that was at least two questions...sorry.

Thanks,

Tom

Tom,

Check your port diameters again. JBL frequently uses slightly odd sized ports. I am not sure, but I seem to remember that the 4333 uses a 4.25" port diameter for instance.

Are you saying that both cabinets now have 2231s without mass rings? Or is one a 2235 without the ring making it a 2234? The 2231 cone is not the same as the 2235 cone, so a 2231 with a 2235 cone minus the ring would be the equivalent to a 2234 where as a 2231 with a 2231 cone minus the ring would be an "other". Is that as confusing as it sounds? The concept is simple and I hope it made sense.

In any event running a 2234 in BassBoxPro with your stated volume and port size gives pretty weak low bass. I have no idea how a 2231 minus the mass ring would perform. I would guess that it would have more bass than a 2234, but still much less than a 2235 or proper 2231.

Mr. Widget

Mr. Widget, I measured the ports and the 4320 is exactly 4" I.D. and the 4333 has a port that maybe could be called 4 1/16" I/D. The 2231s in the 4320s have 2231 cones with the mass rings removed. The 4333s have 2231Hs with 2235H cones with the mass rings removed.
Any recommendations about changing port length, or switching the 2231Hs to the 4320 cabs for a better match?

Tom

"I have no idea how a 2231 minus the mass ring would perform."

Fs = 18.264 Hz
Qms = 4.818
Qes = 0.193
Qts = 0.185

Also, the 2231H suspension isn't quite as "tight" and "linear" as the 2234/2235 suspension, so attack and decay will "suffer" accordingly. In addition, the 2231 can't take as much electrical power input and has slightly greater power compression.

Based on the TS parameters supplied by Giskard the 2231X (my designation) in the 4320 cabinet with the original tuning will give you a very flat response down to -3db of 34.5Hz and a -6dB of 30Hz. This will probably give you an in room response with a hump around 40 to 50Hz. You could lower the tuning to say 28Hz (2-4" X 11" ports) to smooth this out and get just a bit more low end extension.

The 2234 in the 4333 cabinet must be a bit bass shy with the current tuning of (1-4.0625" X 4.25" port) which in a 5.5 cu ft box is a 27.7Hz tuning you will get a -3dB point of 61Hz and -6 db of 36.5Hz.

If you tune the box to 35Hz (1-4.0625" X 1" port) it will give you a -3dB point of 45Hz with a slightly less extended low end.

I would add the mass ring back to the 2235 cone making it a 2235 which in the 4333 cabinet will yield a -3dB of 37Hz and -6dB of 28Hz and a very smooth extended in room response.

I hope this helps.

Widget

Tom,

Did you try the 4333s with the 2235Hs and not like them, or did you go straight to the 2234Hs?

What about a LE14A with the L200B cabinet and XO?

L200(B) box is too big (4.9755 cuft. by my calcs) for LE14A.

BB6P says it wants 4 cuft. for "Extended bass," or 2 cuft. for "High Fidelity" (maximally flat).

Just use 2235H in L200B and concentrate on fixing the VHF.

In L200(A), the same, but close one of the ports with 4" plumbers' test plug for extended bass. Gotta move the Xover down to 800 Hz for that combo, tho, 'cause 2235H doesn't play very nice above 1 kHz..

Add cross-bracing inside the box to reduce LF resonances.

[There's MUCH more better stuff to do with LE14As, anyways.... :thmbsup:]

[There's MUCH more better stuff to do with LE14As, anyways.... :thmbsup:][/quote]
OK, I'll bite. What would you recommend doing with LE14A's? I happen to have a pair looking for a project.

That is the pic Zilch posted above!

Ron

Quote:

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Originally Posted by dmtp

OK, I'll bite. What would you recommend doing with LE14A's? I happen to have a pair looking for a project.

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1) There's the 240Tis, above, though I've never tried that. The "evolved" JBL three-way floor-stander; a Giskard favorite, as I recall.

2) They make very nice subs in Citation 7.4-size boxes (~3.4 cuft. @28 Hz).

3) Members Hamilton and John W have recently made L200T3 clone two-ways with biradial horns; a Zilch favorite. Reduce to 4425 size for "bookshelf."

4) I'm using them in small L55 boxes two-way with 2426H on $9.90 PT waveguides. BB6P says 2 cuft. @~32 Hz is optimally flat alignment for LE14A. :thmbsup:

[Mine are now tuned a bit lower, ~30 Hz; 27.5 Hz was too low.]

5) Smaller still? Build S99 Hotrods using that same 90° x 50° PT waveguide and thread-on compression driver. I've tried 2416H-1, 2418H-1, and 2426H.

John W's project used 2344A horns; the 2342s in Hamilton's version and factory L200T3 are still available new from JBL:

http://audioheritage.org/vbulletin/s...ead.php?t=9695

http://audioheritage.org/vbulletin/s...ead.php?t=8365

LE14's probably the world's most versatile woofer, and among the best sounding -- lotsa good options.... :)