Need help with these JBL 4331B

[Andytn3591]

So I just picked up these 4331B at a really good price without doing any research. When I brought them home, I realized that they had an additional pair of tweeters on them. Then I asked myself how a pair of 2-way speakers have the horns , the driver, and the tweeters. The model of the tweeters is 2405H.
After doing a little of research, I saw people says that these 4331B can be converted to the 4333B/L300. I took out the woofer and saw that they had a pair of 3105 Dividing network in them. I hooked up the speakers to my receiver and the sound was weird. It was not clear, the bass was not deep enough. So my questions are :

1/ What's the purpose of the 3105 Dividing network in the speakers ?
2/ Have these 4331B been converted to 3-way speakers correctly ?
3/ If yes, how to hook them up correctly to get the sound right ? I'm not familiar with bi-amp, etc ....
4/ The 15" Woofers model is 130H. I don't have any info on these. What are they ? Are they original with the 4331B ?

Thank you.

 

[toddalin]

1/2/3 The 3105 is the 7,000 Hz crossover actually intended for the 2402/075 (bullet) tweeter, which actually uses the same magnet assembly, but a different "taper" and a different diaphragm. The 3106, 8,000 Hz crossover was actually the "correct" one for the 2405/077, but you can use the 3105 in a pinch. The 4333/L300 tweeter sections of those crossovers were actually a bit different than either of these at about 8,500 Hz.

4 The correct woofer is the 2231 but many of the woofers, including a 130H could be reconed as 2231/2235s with the same results. the 130H was actually a PA/musical instrument speaker.

Does your woofer have a foam edge or the original "double roll?" If it was reconed, it should have a foam edge. The double rolled edge of the 130 does not provide the bass response of the foam edge. OTOH, it has a more lively sound.

Also, your woofer is from a different "generation" with a ferrite as opposed to an AlNiCo magnet on the horn driver. Tweeter may also be from the later generation and you can tell by looking at/feeling the magnet.

 

[Andytn3591]

1/2/3 The 3105 is the 7,000 Hz crossover actually intended for the 2402/075 (bullet) tweeter, which actually uses the same magnet assembly, but a different "taper" and a different diaphragm. The 3106, 8,000 Hz crossover was actually the "correct" one for the 2405/077, but you can use the 3105 in a pinch. The 4333/L300 tweeter sections of those crossovers were actually a bit different than either of these at about 8,500 Hz.

4 The correct woofer is the 2231 but many of the woofers, including a 130H could be reconed as 2231/2235s with the same results. the 130H was actually a PA/musical instrument speaker.

Does your woofer have a foam edge or the original "double roll?" If it was reconed, it should have a foam edge. The double rolled edge of the 130 does not provide the bass response of the foam edge. OTOH, it has a more lively sound.

Also, your woofer is from a different "generation" with a ferrite as opposed to an AlNiCo magnet on the horn driver. Tweeter may also be from the later generation and you can tell by looking at/feeling the magnet.

Thank you for your help.

It seems like the woofers have "double roll"

I have to say that if the 4430 is 10/10 , the 4331 is only about 6/10 for the sound quality.
Idk if I hook them up correctly since the added 3105 network makes me confused. The horns and the tweeter sound so quiet right now. For the way they're set up right now, do I have to bridge the connectors in order to makes them work correctly ? Or should I just hook them up to the "internal crossover" ? I need to confirm it before doing stupid things

 

[toddalin]

Thank you for your help.

It seems like the woofers have "double roll"

I have to say that if the 4430 is 10/10 , the 4331 is only about 6/10 for the sound quality.
Idk if I hook them up correctly since the added 3105 network makes me confused. The horns and the tweeter sound so quiet right now. For the way they're set up right now, do I have to bridge the connectors in order to makes them work correctly ? Or should I just hook them up to the "internal crossover" ? I need to confirm it before doing stupid things

I don't think you have them connected properly. First off, it seems weird that the crossover would state "System Crossover 300 Hz" when the horn actually crosses over at 800 Hz. Anyway, the 3131A schematic should be similar, (not identical though because note that the schematic specifies 30 watts for the horn as opposed to yours which say 75 watts) and I've included it.

Using the "internal crossover", you should take the two wires originally intended to go to the horn and run them into the input of the 3105. Run #1 output (low) of the 3105 to the horn +, #2 to the horn -, #3 to the tweeter (High) -, and #4 to the tweeter +.

\http://www.jblproservice.com/pdf/Network Schematics/3131A Network.pdf

http://www.jblproservice.com/pdf/Network Schematics/3105 Network.pdf

 

[GordonW]

1/2/3 The 3105 is the 7,000 Hz crossover actually intended for the 2402/075 (bullet) tweeter, which actually uses the same magnet assembly, but a different "taper" and a different diaphragm. The 3106, 8,000 Hz crossover was actually the "correct" one for the 2405/077, but you can use the 3105 in a pinch. The 4333/L300 tweeter sections of those crossovers were actually a bit different than either of these at about 8,500 Hz.

4 The correct woofer is the 2231 but many of the woofers, including a 130H could be reconed as 2231/2235s with the same results. the 130H was actually a PA/musical instrument speaker.

Does your woofer have a foam edge or the original "double roll?" If it was reconed, it should have a foam edge. The double rolled edge of the 130 does not provide the bass response of the foam edge. OTOH, it has a more lively sound.

Also, your woofer is from a different "generation" with a ferrite as opposed to an AlNiCo magnet on the horn driver. Tweeter may also be from the later generation and you can tell by looking at/feeling the magnet.

A few notes about this:

- The 2231A is the same frame and magnet as the 2205A, 135A, 136A, D130 (preferably 1960 or later), K130, D140 and K140 Any of those with 2231/2235 kit in it, will result in the same acoustics as a 2231A.

- The 2205H, 2225H, 2231H, 2235H and 136H can all be reconed to be a 2235H. That is also an acceptable acoustic sub for a 2231A/136A.

- The 130A, 130H, E130 (and the consumer version, the rare D130H), E140, 2220A, 2220H, K145, E145, LE15A and LE15B all have DIFFERENT magnet structures than the 2231 and 2235. They CANNOT be properly reconed with a 2231/2235 kit. The magnet top plate thickness and/or the magnetic strength on these is different from the 2231/2235. The voice coil will not line up with the top plate correctly in most of these- and even those that have the same top plate thickness, have different thickness and strength magnets. That would upset the electrical Q, which upsets the needed box tuning...

Regards,
Gordon.

 

[toddalin]

So then a 130H is not the same as a D130 (as I thought) but like a 130A and reconing it this way creates a "Frankenwoofer."

 

[toddalin]

Another thing to consider.

I had 130A woofers (AlNiCo 16 ohm versions of yours) in my L200 cabinets and they had little real bass. I pulled them out and had three 2205 AlNiCo woofers reconed as 2235s (a legit swap and not a Frankenwoofer).

I instantly regretted how "dead" the speakers became, and I even had all magnets (woofers, mids and tweets) recharged at the time. In fact, I removed the three woofers (L/C/R), and took them back to Orange County Speaker, and had them recharged again, which did raise the BL a bit (now >22).

But I still feel that the speakers lost their livelyness and became tubby, and if I did it again, I would have either had the woofers reconed as 2234s (i.e., leave out the mass rings), or just kept the 130As and added a sub, which I did anyways. The standard 130A cones will provide more "slam" and better vocal rendition than the 2235s as well as more efficiency. But you give up some bass, and should retune the cabinet ports to different specs to make the most of them.

 

[GordonW]

So then a 130H is not the same as a D130 (as I thought) but like a 130A and reconing it this way creates a "Frankenwoofer."

The D130H is an E130.

Apparently, a 130H (no "D" in front), SHOULD be like a 2220H.

The way to tell for sure, is to look at the magnet top plate. If it's only about 1/4" thick, it's an E130. If it's almost a half inch thick, than it's a 2220, effectively.

However- the magnet is wrong on both of those, for a 2235. Too thick top plate on the 2220/130H, and too much magnet strength in the E130/D130H.

Speaking of 2235- as alluded to above- any time you build a 2235, you can always leave out the mass ring, and try it as a 2234. If you later want to go to the 2235 spec, all you have to do is cut off the dust cap, install the mass ring, and put on a new dust cap. The 2234 will be more efficient in the mids.

Regards,
Gordon.