JBL 4311's = system complete... for now.

[oconnorweb]

I am hoping someone can give me some advice on the JBL 4312 crossover.

I got the foilcals off the screws and the crossovers out. I know this is not a difficult recap but its a bit over my experience level. I am sure this is a fairly easy issue but I want to make sure I get this right.....

So my crossovers already have the .01 bypass caps installed. Here they are:




Well prior posts on this thread (its really helpful btw) show the .01 bypass caps installed in parallel with the two 4 uF Dayton caps and the one 3 uF Dayton cap. I copied some pics here:



My newbie question is this; should I just install the .0.01 uf AudioCap Theta's where the .01 caps are currently located or should I follow the other posters here and place them in parallel with the new caps? It looks like if I do that there will only be wiring to 2 of the 3 connections on the high freq L pad?

My guess its the same result? What's the easier/don't mess up option?

Is it ok to just get one 8.2 uF cap instead of the two 4 uF's?

Last newbie question, assuming I just follow exacting what I have now and replace the L Pads and caps right where they are now located, where's the best place to start? The two 4 uF caps, the 3 uF cap, and the .01 caps and then the L Pads or visa versa? Sorry if this is stupid stuff but I am a bit confused.

Thanks for any help guys.....

 

[Michelag]

I am hoping someone can give me some advice on the JBL 4312 crossover.

I got the foilcals off the screws and the crossovers out. I know this is not a difficult recap but its a bit over my experience level. I am sure this is a fairly easy issue but I want to make sure I get this right.....

So my crossovers already have the .01 bypass caps installed. Here they are:

View attachment 1674656 View attachment 1674657 View attachment 1674658


Well prior posts on this thread (its really helpful btw) show the .01 bypass caps installed in parallel with the two 4 uF Dayton caps and the one 3 uF Dayton cap. I copied some pics here:

View attachment 1674660 View attachment 1674661 View attachment 1674662 View attachment 1674663

My newbie question is this; should I just install the .0.01 uf AudioCap Theta's where the .01 caps are currently located or should I follow the other posters here and place them in parallel with the new caps? It looks like if I do that there will only be wiring to 2 of the 3 connections on the high freq L pad?

My guess its the same result? What's the easier/don't mess up option?

Is it ok to just get one 8.2 uF cap instead of the two 4 uF's?

Last newbie question, assuming I just follow exacting what I have now and replace the L Pads and caps right where they are now located, where's the best place to start? The two 4 uF caps, the 3 uF cap, and the .01 caps and then the L Pads or visa versa? Sorry if this is stupid stuff but I am a bit confused.

Thanks for any help guys.....

If you follow the wiring you'll discover the small are in parallel with the big.
You can do whatever, I did them parallel because I prefer order...

Second, with an hairdryer I let the glue start to melt, then removed the bigger one, and installed the new cap on the glue...
Small caps you remove them by cutting the wire...
Then same for the other big cap...
Beware the order 1 2 3 in the l pads, there is the only point you have to pay attention

 

[oconnorweb]

If you follow the wiring you'll discover the small are in parallel with the big.
You can do whatever, I did them parallel because I prefer order...

Second, with an hairdryer I let the glue start to melt, then removed the bigger one, and installed the new cap on the glue...
Small caps you remove them by cutting the wire...
Then same for the other big cap...
Beware the order 1 2 3 in the l pads, there is the only point you have to pay attention

So I'm right that the current set up has the .01's in parallel with the big caps? I may just leave it the current way and swap out the components so I don't screw it up. Safer and OK?

 

[Michelag]

So I'm right that the current set up has the .01's in parallel with the big caps? I may just leave it the current way and swap out the components so I don't screw it up. Safer and OK?

as you prefer... it's really the same

 

[drumbum]

I am hoping someone can give me some advice on the JBL 4312 crossover.

I got the foilcals off the screws and the crossovers out. I know this is not a difficult recap but its a bit over my experience level. I am sure this is a fairly easy issue but I want to make sure I get this right.....

So my crossovers already have the .01 bypass caps installed. Here they are:

View attachment 1674656 View attachment 1674657 View attachment 1674658


Well prior posts on this thread (its really helpful btw) show the .01 bypass caps installed in parallel with the two 4 uF Dayton caps and the one 3 uF Dayton cap. I copied some pics here:

View attachment 1674660 View attachment 1674661 View attachment 1674662 View attachment 1674663

My newbie question is this; should I just install the .0.01 uf AudioCap Theta's where the .01 caps are currently located or should I follow the other posters here and place them in parallel with the new caps? It looks like if I do that there will only be wiring to 2 of the 3 connections on the high freq L pad?

My guess its the same result? What's the easier/don't mess up option?

Is it ok to just get one 8.2 uF cap instead of the two 4 uF's?

Last newbie question, assuming I just follow exacting what I have now and replace the L Pads and caps right where they are now located, where's the best place to start? The two 4 uF caps, the 3 uF cap, and the .01 caps and then the L Pads or visa versa? Sorry if this is stupid stuff but I am a bit confused.

Thanks for any help guys.....

Have you tested the caps you removed from the loudspeaker?

I tested some recently and they were fine. Tested the caps from my pairs of Imperial 6's and they were also fine.

 

[Michelag]

So I'm right that the current set up has the .01's in parallel with the big caps? I may just leave it the current way and swap out the components so I don't screw it up. Safer and OK?

done?

 

[oconnorweb]

done?

Caps, L Pads and new binding posts are coming today from PE! Plan on getting to it as soon as I can.

I've repaired the small tear in one woofer with glue and white coffee filter. Worked well.

There was some gooey black stuff running from the bottom of the woofers. I've read that is common. Heated that stuff up with dryer and scrapped it off carefully.

I also need to clean up the cabinets.....

 

[oconnorweb]

I read the above posts again. I am taking a chance that new caps will help. The sound was plain bad. In the past a recap has helped a lot.

The drivers all tested OK in capacitance. I hope the new crossover will make these baby's sing again.

 

[Terminal]

The system that you have is vintage, very old and should be restored to sound as good as it did new.

Having said that, neither the 4312 (non-A) nor the 2235 are really known for brightness nor speed, especially in the higher octaves. It is one of the reasons I have no vintage Marantz, it is more of a "warm" sound where I prefer more detail.

Was your 2235 a better sound on brighter speakers? The 4312 is a nice collectible speaker, but lacks the sizzle of a modern unit, the 4312A was much better at producing HF as were any of their dome-tweeter speakers.

Yes there is an electrolytic cap in the crossover that should be replaced, not sure but I think that the cap in the sand-filled tube is a film cap.

Uuuummmh, nonsense.
this thread is about all the very common problems with 4311s, if the extent of service by the speakers previous owner was to flood deoxit down the shaft of the L-pads I think it is safe to say these speakers are probably in need of some service ( like most unrestored 4311s). blanket generalizations about Marantz amps? give us a break please....
I would like to sit you in front of my 2285B with some LaScalas and show you what bright ( and "fast" ) sounds like!! or you could just listen to how they sound with my vintage Cabasse speakers and realize that generalizations fail us all.
Most vintage Marantz amps have what is described as a warm sound -and- they are excellent for classic material. I have been listening to Bach, Callas, and Blakely tonight and have no complaints about the range or dynamism of the sound because the 4311 is not the speaker I find ideal for that material.
I would recommend the OP try a different set of speakers ( while restoring his 4311s!!) or even a good set of headphones with his amp to confirm the 4311s are the weak link, and to look into doing the repairs/upgrades detailed in this thread to bring his speakers back to the original condition ( or the "Bright" modification ) so he can really enjoy them.

 

[SaturationPt]

Welcome to the forum Terminal.

Yes, out of my many marantz receivers I found the 2285 and 2265B to be the best at producing HF detail, but in general I feel that they (all fully restored and/or when new) are warmer and less detailed than their contemporaries from Pioneer, Onkyo, McIntosh. If I could have one of my 22xx/23xx receivers back it would be the 2285. Generalizations are valid if they cover the general population regardless of whether there are outliers. I have also had horns, not my first system here, we all have our preferences and that's why in the '70s our store sold many lines other than marantz.

This thread is about the JBL monitors, and interactions between the sources and entire audio chain are extremely important when assessing a pair of speakers, I expressed an experienced opinion that there are brigher receivers that will help the system produce better HF with the LE25 tweeters (although then you need to deal with the response of the LE-5 which can overwhelm toward the top). If the OP's taste leans toward more HF there are ways to get there.

 

[oconnorweb]

done?

I recapped and replaced the L Pads on one speaker tonight. Here is a pic of the new caps installed...forgot to take a pic after I replaced the LCaps....



I know. Not the best soldering but not a lot of experience.

I made a couple of mistakes that slowed me down but finished the first one. Hooked it up in mono just to make sure I got all 3 drivers working and no hum etc. Well I am very pleased. So much better sounding. Night and day! I don't know if its the caps or the L Pads or a combination of them both. Really glad I replaced all components after all the work in getting that crossover out. I will likely get the other done Friday so I can do some critical listening. I did get the cabinets cleaned up too. I will post some pics of the finished product when done.

Thanks for all the help -

 

[oconnorweb]

Finished up the other speaker. Again the sound is a huge improvement with the recap and new L Pads. Also replaced the posts while I was in there. I do recommend the work if anyone is on the fence.

I am going to enjoy them awhile in my main system. It's interesting that with certain genre or even particular songs they sound as very good; as good as my ADS L810's ; with other materials I hear a weakness. Some booming bass. Some mixed mids and highs. Hard to explain but definitely there. Is this inherent with these monitors or does anyone have any thoughts on mods to correct?

Here are some pics of the finished product.

View attachment 1686519 View attachment 1686519

 

[Michelag]

Finished up the other speaker. Again the sound is a huge improvement with the recap and new L Pads. Also replaced the posts while I was in there. I do recommend the work if anyone is on the fence.

I am going to enjoy them awhile in my main system. It's interesting that with certain genre or even particular songs they sound as very good; as good as my ADS L810's ; with other materials I hear a weakness. Some booming bass. Some mixed mids and highs. Hard to explain but definitely there. Is this inherent with these monitors or does anyone have any thoughts on mods to correct?

Here are some pics of the finished product.

View attachment 1686519 View attachment 1686519 View attachment 1686520 View attachment 1686521 View attachment 1686522 View attachment 1686523 View attachment 1686524 View attachment 1686525

hi Oconnor,
very happy to hear that it made a significative difference...
my 0,02€ on your points:
booming bass is usually question of positioning. I've got your same stands, I found out that placing the speakers at 50-60 cm from the floor helps a lot, since the floor is mirroring or even conducing lower frequencies;
after many tests, hard to explain, i found out that the "neutral" flat curve is obtained with the pots around "8", that's what gives me a good listening for classical music as well.
put the speakers at a distance not less than 1,5m one each other.
this is my personal experience, hope it helps.

 

[Jayrosc]

So this pair of old 4311wx's I got last week started out great but it looks like new caps are needed. One of the mid ranges started to crackle and drop in and out so I pulled the woofer and got some deoxit in the pots. Crackle is gone as is the dropping in and out but the mid only produces about half the volume of the mid on the other speaker in the pair. Here's the problem: I noticed the pots on these are tiny. Like only 3/4 inch in diameter. When I changed the pots in a pair of 4312's couple years back those pots were large, like an inch and a half in diameter. Are there suitably sized replacements out there for these 4311's? I had no trouble getting Dayton pots for the 4312's. These little guys are harder to track down. Took a pic of the knobs. They do not look like others I've seen on 4311's and 4312's. Perhaps this is a very early generation of these speakers?

 

[Nosmo]

A huge thank you for this thread. I have just completed an update to a pair of 1974 JBL 4311wx,s.
New caps and L-Pads. So far so good. However I found an error in member "Brainwashed" parts list on page one of this thread.
The L-Pads required are 1" Shaft length not 3/8" as shown. Correct part number is 260-250 and it's a stock item.

 

[Hannes123]

Hey! I will also renovate my 4311WX and i opted for these caps...Can anyone tell me how to bring them in the right order when glueing them on the cardboard?
I need 8 caps, apprently, but is there a picture where someone did his xover with these caps so that i get the idea? My LPads seem to work fine, one is crackling but you can´t hardly hear it, i guess i just clean them with DeOxid. I will also get them repainted in utility grey so the only thing that haunts me is the removal of the aluminium badge. Someone has already done that before on mine so they already don´t look like new. They will mostly be used with a restored Fisher 500c - i hope these caps will work well with the 500c

"CAPS FOR REBUILDING A PAIR OF JBL 3112 NETWORKS YEILDING A "MELLOW" SOUND
ClarityCap PX range
You'll want to select the Value from the dropdown menu, and type in the quantity:
Value=1.5uf Quantity:4
Value=3.3uf Quantity:2
Value=4.7uf Quantity:2"

Thanks

 

[Pier]

Sorry for my not perfect language, I'm Italian and I rely on Google for the translation. I wanted to give my contribution to this 3ad with this little job done by me at home. It is not a new job but done 33 months ago. I treated the piece of furniture with sandpaper 400, shellac and wax finish. Didn't need to replace the L PADs, they still worked fine, opened and cleaned them with an electronic contact spray cleaner, new binding posts new Jantzen Audio Silver Cap capacitors and rewired with Van Den Hul CS 12 wire and silver wire from the capacitors to the L PAD. I decided to publish it because I finally found some photos that I thought I had lost, others I have redone. I do not publish them all because the old Xover is known to all as well as how the foilcals are removed. Of course this forum was of great help and inspiration to me for the electronic part, another site is that of the well-known and talented Japanese who modifies and resurrects every JBL model. I am satisfied with the work and the result obtained both aesthetic and sonic but I would like to know the beryllium Tweeter model that it uses on some 4311B since the original LE25 2 do not have a great frequency response, they do not go beyond 15khz or alternatively a supertweeter to cover the range above 15khz. Some advice?

 

[grindstone]

Nice. Welcome

 

[Pier]

Has anyone experimented with bi-wiring? If I find a tweeter to adapt without changing the aesthetics of the front panel I think I will experiment, bi-wiring I don't think it will bring benefits but it certainly won't make anything worse.

 

[PMB]

Just replaced my L-Pads with Monocors, and caps with Jantzen standards. I went 3.3uf and 8.2uf. They sound fantastic! However, what caps would people suggest as a significant upgrade? Without breaking the bank!