4313B Details

[Guido]

I managed to get the complete set of 4313B components including original xovers for a very reasonable price (appr. 100 USD)
:dancin:

Now I need your help with the cabinet.

What is the size of the back enclosure for the LE5?
What is the diameter and duct of the port?

another Question: What is the difference between a 044 and a 066 tweeter?

Thanks!

[4313B]

Hi Guido,

I'll send you a couple of 4313 ports/ducts with your 2121H's along with the L-Pad knobs you requested. The subenclosures for the LE5's are supposed to be ~ 80 cubic inches internal volume. One that I have measures 5-5/16 ID x 3-5/16 deep. External dimensions are 5-11/16 OD x 3-15/16 deep. The little 3.5 mH 7.5 ohm DCR parallel air-core inductor in many of the JBL networks flattens out the impedance at the resonant frequency of the LE5 in this subenclosure.

The 066 has an aluminum voice coil for lower moving mass and the 044 has a copper voice coil for greater power handling. Both are phenolic domes with aluminum coatings applied via vapor deposition. For comparison the 033 has the same phenolic dome without the thin layer of aluminum so it is a soft dome. The 044 is down 6 dB at ~ 18 kHz and the 066 is down 6 dB at ~ 21 kHz.

One can use the 044 in place of the 066 in a DIY 4313 if desired. One can also use the deeper L96 enclosure. The port/duct is the same for both enclosures which means the shallower 4313 enclosure is tuned a bit higher. The Fb of the L96 is ~ 32 Hz.

When the 4313 was brought to market it was considered the most "accurate" loudspeaker system JBL had ever produced.


Here's a little matrix for those who might be interested.

Note - None of the 4313 systems used bypass capacitors. For some reason it took Pro a few years to catch up to Home (Consumer) and employ them. I think the 4411 (JBL L112 Century II in Pro attire with the completely different 3109 network) was the first to use the little poly bypass caps. The point is, it's not a bad idea to install the 61098 bypass caps in the 4313's and the original L110's. ;)

Note - The N96 in the L96 is the same network as the N112 in the L112 and the N150A in the L150A. The different network model numbers denote the different wire lengths and foilcals.

I'll post scans of brand new 4313B and L96 foilcals in a few days for those who want to recreate them.

[Guido]

:hmm: :hmm: :hmm:

Giskard, one day you must tell me the login to the JBL intranet.

This is an ANSWER!

One could easily see that the 4313B is your favourite bookshelf speaker. In fact this statement induced me to press the BIN button on this auction.

I'm curious to hear this L96 / 4313B DIY.

I read in an older post that you prefer the 4313B network over the L96. Well I decided to modify the L96 networks to 4313 networks after simulating both with circuit maker.

Thanks for your help!

[Earl K]

I've brought into this thread, a second matrix of le5 info created by Giskard.

I think they are both darn useful and ought to be seen together .

regards <> Earl K

[Mats Nilsson]

Would the deimensions posted by Giskard be internal or external dimensions?(23,5x14,25x9,9375). Thinking of using 1" MDF, not sure how the 4313B where built originally.

[duaneage]

I believe they were external dimentions. At least that is what my 4411 measures so taht should be true for the other dimensions. You should be able to use 3/4 Inch MDF for a cabinet of that size. The o44 and o66 tweeters were designed to be mounted through 3/4 material so using thicker would require relief cutting of 1/4 inch on the rear.


Internal bracing is important, I used 1x1 inch hardwood for bracing along the edges and sides.

[Malefoda]

Hi fellows,
Ok 32Hz for the resonant frequency of the L96, but what is the one of the 4313B? Closer to 38/40?
Thanks!

[hjames]

Hi fellows,
Ok 32Hz for the resonant frequency of the L96, but what is the one of the 4313B? Closer to 38/40?
Thanks!

Resurrect a DEAD Thread -
... bring this ZOMBIE back to life after 12 YEARS!

[Malefoda]

Hi,
I am sorry if it is not allowed, should I open a new thread?
Thanks

[pos]

IMHO reviving old threads that way (ie not responding to an old ad or any other anachronism, and simply being aware of the situation) is perfectly fine and probably better than opening a new thread as far as coherency and information retrieval is concerned.
The problem that often occurs in such situations though is with subsequent posts from other people seeing a "new" thread (re)appear and responding to old posts without noticing the time gap...

[turnitdown]

I found this in a search for the diameter and length of the port for the 4313. I am building a pair and this thread came THIS close but no ceegar for the dimensions. Anyone?

[Malefoda]

On mine, 7cm inner diameter and outside (longest) elbow lengh roughly 27.5cm. Hope that helps.

[turnitdown]

THANKS Malefoda! That did it. I put those figures into WinISD and it works. F3 @ about 44Hz.

[Malefoda]

Mind that lenght of the pipe is a bit less as inner side of the 90° elbow is a bit shorter. Maybe you calculated with that taken into account?

[turnitdown]

Yes, I did change the measurements around to best match the driver and box but I used your dimensions as a start. They were VERY close.

[Malefoda]

:cool:
Well done!