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Jbl 4331b

So I am still deciding whether or not to leave these speakers original or modify to 4333A specifications. Would I be messing with the value of these on a resale? I'm thinking now of just cleaning these up and try to hold on to them as long as I can (wife doesn't appreciate the size). I should be getting them back from the cabinetmaker in two weeks and he is re veneering them in the original mahogany finish and I have found everything else besides grilles and grille badges. The original crossovers are being cleaned up and recapped as we speak so they should sound pretty sweet as they are. Am I really getting a superior speaker by changing them out to 4333 specs and will I be getting a better resale value selling them as 4333's? So many questions and as I'm not handy with electronics or woodworking I'll probably have 2000.00 (Can) tied up in them just redoing them in their original form. Any feedback would be appreciated and does anybody know where I can find a good picture of the original grilles for this model as I'll have to get them made from scratch.
 
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My opinion - worth every penny it cost - modified they are no longer 4331 or 4333. If resale is not in the picture, all bets are off. Make them what YOU want.
 
Personally, it isn't very expensive to convert to a 4333 - the 2405H's with OEM diaphragms may set you back $250 and mods to crossover another $50-100 or so, then you can evaluate and see if it sounds better to you or not. You won't lose anything if you don't like it because its essentially reversible (unless you cut a hole for the N8000 instead of mounting it inside), and selling the parts will essentially net you the same in return if you sell them correctly. To some, the additional parts are a natural upgrade to the 4333A/B/L300, and having a nice walnut cabinet is a plus over the gray utility cabinet.
 
mech986 said:
I wouldn't bother with building the lenses unless you want to do the wood work, they have a specific angle and spacing and cutout to do the right job at the right frequencies. There are already good reproductions at Kenrick and the price isn't terrible considering the time and effort to reproduce them on your own.

As for veneer, SAEMAN or the Rick in Kenrick veneered many large format JBL Monitors in Rosewood which were just spectacular.

you can easily upgrade the 4331a to a 4333 by adding a separate crossover for an 077 or less expensive 2405 tweeter, the crossover to use is the N7000, or you can add something similar (just the circuitry) into the existing crossover and be sure to add the crossover L-Pad for adjustment of output. you may then have to get a new foilcal as the existing foilcal would cover where the new L-pad normally would go. Or you could just position the new L-pad past where the current foilcal edge ends.
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I'm liking your idea of adding the N8000 crossover with the extra pair of tweeters I have (077's not 2405's) and hiding them (crossovers) inside the cabinet. As I won't be doing the actual wiring and mounting I will be asking my tech guy to do this for me for so I was wondering where i might get a picture or wiring diagram that I can hand to my guy. My tech guy is in the process of cleaning up and recapping the original crossover right now (3131A) and I would like to find a set of N8000's and get them to him ASAP. I will also need to find a new set of foilcals and L-Pads which I don't mind mounting on the front where they would normally be. Any help on a diagram or a picture would be appreciated. Thanks a lot for all the feedback above.
 
mike1955 said:
I'm liking your idea of adding the N8000 crossover with the extra pair of tweeters I have (077's not 2405's) and hiding them (crossovers) inside the cabinet. As I won't be doing the actual wiring and mounting I will be asking my tech guy to do this for me for so I was wondering where i might get a picture or wiring diagram that I can hand to my guy. My tech guy is in the process of cleaning up and recapping the original crossover right now (3131A) and I would like to find a set of N8000's and get them to him ASAP. I will also need to find a new set of foilcals and L-Pads which I don't mind mounting on the front where they would normally be. Any help on a diagram or a picture would be appreciated. Thanks a lot for all the feedback above.
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Here is the JBL 4331B from the JBL Professional site under Support, then Service, or directly under www.jblproservice.com, then "Exploded Views", then Studio Series. Direct link to tech sheet:
http://www.jblproservice.com/pdf/Studio Monitor Series/4331B.pdf
Direct link to 3131A crossover network:
http://www.jblproservice.com/pdf/Network Schematics/3131A Network.pdf

Here's the corresponding info for the 4333B:
http://www.jblproservice.com/pdf/Studio Monitor Series/4333B.pdf
Direct link to 3133A crossover network:
http://www.jblproservice.com/pdf/Network Schematics/3133A Network.pdf

Here is the 3106 pro network which is identical to the N8000 for use with the LE85/2420 mid compression driver and 075/077/2405
http://www.jblproservice.com/pdf/Network Schematics/3106 Network.pdf

Personally, I would create the HF section (2405) section of the 3133A by adding the 1.0uf cap and moving the 1.5mf cap behind the 0.16mh inductor of the 3106. This creates the 3 element (2 caps and 1 inductor) 18db/decade crossover point for the 077 instead of the 2 element (1 cap and 1 inductor) 12db/decade crossover point of the N8000. You can see the LF (really MF) section of the N8000 is added on to the MF section of the 3131A so that comprises the MF section of the 3133A. That way, you don't have to have the outboard box of the N8000 and all the wiring, but add it directly to the 3131A box.

Zonker92 said:
You could just have him build these crossovers: http://www.firstwatt.com/pdf/art_l300.pdf
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that would be another great option. Interesting choices with the 077. However, this assumes, as stated in the article, driving the speakers to less than maximum volume, even though he states he uses up to a 600 watt amp.
 
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Zonker92 said:
You could just have him build these crossovers: http://www.firstwatt.com/pdf/art_l300.pdf
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Your darn right, I would love to have those crossovers. I read Nelsons article as well and if he's happy with his L-300's I'm sure I would be in heaven. I got to admit though I've been using my Jubals while the cabinets are getting done and they are a damn fine little speaker in their own right. I think I'll just keep them as a backup set or wire them as my upstairs speakers as my wife doesn't mind the look of the Jubals (little glass top end tables).
 
mech986 said:
Here is the JBL 4331B from the JBL Professional site under Support, then Service, or directly under www.jblproservice.com, then "Exploded Views", then Studio Series. Direct link to tech sheet:
http://www.jblproservice.com/pdf/Studio Monitor Series/4331B.pdf
Direct link to 3131A crossover network:
http://www.jblproservice.com/pdf/Network Schematics/3131A Network.pdf

Here's the corresponding info for the 4333B:
http://www.jblproservice.com/pdf/Studio Monitor Series/4333B.pdf
Direct link to 3133A crossover network:
http://www.jblproservice.com/pdf/Network Schematics/3133A Network.pdf

Here is the 3106 pro network which is identical to the N8000 for use with the LE85/2420 mid compression driver and 075/077/2405
http://www.jblproservice.com/pdf/Network Schematics/3106 Network.pdf

Personally, I would create the HF section (2405) section of the 3133A by adding the 1.0uf cap and moving the 1.5mf cap behind the 0.16mh inductor of the 3106. This creates the 3 element (2 caps and 1 inductor) 18db/decade crossover point for the 077 instead of the 2 element (1 cap and 1 inductor) 12db/decade crossover point of the N8000. You can see the LF (really MF) section of the N8000 is added on to the MF section of the 3131A so that comprises the MF section of the 3133A. That way, you don't have to have the outboard box of the N8000 and all the wiring, but add it directly to the 3131A box.



that would be another great option. Interesting choices with the 077. However, this assumes, as stated in the article, driving the speakers to less than maximum volume, even though he states he uses up to a 600 watt amp.
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Yes I'm sure Nelson Pass has amplifiers we can only dream of at his disposal. I'm driving my speakers with a Bryston 4B SST and it's more than ample right now. I have a second Bryston 4BST that I can use as well when it comes back from service at Bryston in a couple of weeks. Two 4B's would do the job pretty good I would think running them as two mono amplifiers.
 
Brad Muller said:
I bought the Kendrick lenses and am very pleased with them for $130. It's a no brainer.
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Yes, I did the same thing and just got them a week ago. They look and function quite well, now I just need to build some grilles for these babies although they won't be on the speakers very much ;)
 
Wouldn't have been me, I only see great possibilities. Did you have a thread on those? Was one who laughed your spouse? So what was the story with them?
 
Ya, there is an old thread. I don't think you can go wrong with any of the big blue faced 43xx series monitors. They are the real deal.
 
Take your time. It's worth it in the end. I even used new screws, although I had to paint them. If you can upgrade with the prism tweeter.....you won't be sorry!
 
Brad Muller said:
Take your time. It's worth it in the end. I even used new screws, although I had to paint them. If you can upgrade with the prism tweeter.....you won't be sorry!
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Yes I'm going to keep an eye out for a pair of proper crossovers but in the meantime I don't want to do anything to them that would ultimately detract their resale value. I plan on keeping them but you never know and I think keeping them as stock as possible is always a good idea.
 
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