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Newbie needs ID on JBL I

motorcityguy

motorcityguy

Active Member
I picked these up at and estate sale. I think they are JBL, but I can find no identification on them. Can anyone help identify what they are?

PS, I fat fingered the title to the thread and there does not seem to be a way to edit it.

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90% sure JBL's L-100's 4311?
Not sure about the port location.
Do they work ? Looks like new foam around the Tweeters. and taken care of.
How much did you steel them for?
Bobhorn
 
Nyjblbob said:
90% sure JBL's L-100's 4311?
Not sure about the port location.
Do they work ? Looks like new foam around the Tweeters. and taken care of.
How much did you steel them for?
Bobhorn
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I was able to hook them up and confirm that they work well. Not sure about the history, but the wood cabinets are in beautiful condition. Just surprised that the wire connections or the L-pad have no emblem or identification. So, you're thinking they are 4311?
 
They’re not L100A, look like 4311s with the foilcal removed.

BTW, they’re upside-down.

The foilcal typically is removed to get to the two phillips screws and service the crossover, if the PO had removed them and damaged them that is not surprising, if they were stored separately they might have simply been misplaced.
 
SaturationPt said:
They’re not L100A, look like 4311s with the foilcal removed.

BTW, they’re upside-down.

The foilcal typically is removed to get to the two phillips screws and service the crossover, if the PO had removed them and damaged them that is not surprising, if they were stored separately they might have simply been misplaced.
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Thanks! Are they any good? I simply made sure they worked, and didn't perform any critical listening. (Might be a while before I can get them home). Is the "label/decal" available?
 
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Hell Yea! Either Loved or Dispised, But it was the Bookshelf to beat. Go price a mint pair
n Looks like they were babied.
Bobhorn
 
Nyjblbob said:
Hell Yea! Either Loved or Dispised, But it was the Bookshelf to beat. Go price a mint pair
n Looks like they were babied.
Bobhorn
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Bookshelf? LOL, they're actually pretty big.... But, yes, they are cosmetically mint. What did they originally use for grills? Mine have nothing. Guessing they were maybe originally that awful foam? I can probably make some from Masonite and cover it with black grill cloth, but would be nice to know what they are "supposed" to have.
 
Black grille cloth, frames held on by velcro.

As they were designed to be studio monitors, most of them were in studios without grilles. Search google for images and you’ll see the grille design, doesn’t cover the trim pots.
 
SaturationPt said:
Black grille cloth, frames held on by velcro.

As they were designed to be studio monitors, most of them were in studios without grilles. Search google for images and you’ll see the grille design, doesn’t cover the trim pots.
Click to expand...

Thanks! Now that I know they are 4311, it's a lot easier to search for representative images. Looks like a guy on that auction site sells new repro grills in variety of colors.

Also looks like there are (or were?) some repro decals for model number. That leads me to next question: Is there an easy way to tell if these are 4311, 4311A, or 4311B? Or do I need to pull the drivers? I may need to do that anyway, in order to see if crossovers have been updated (and if THAT is the reason the name plates are missing).
 
motorcityguy said:
Thanks! Now that I know they are 4311, it's a lot easier to search for representative images. Looks like a guy on that auction site sells new repro grills in variety of colors.

Also looks like there are (or were?) some repro decals for model number. That leads me to next question: Is there an easy way to tell if these are 4311, 4311A, or 4311B? Or do I need to pull the drivers? I may need to do that anyway, in order to see if crossovers have been updated (and if THAT is the reason the name plates are missing).
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The 4311- or A same, Alnico Magnets on at least the woofers, Ceramic magnet Woofer, the mids and tweets not too sure.
 
Okay, so I went ahead and tried to open them up. Woofers are labeled 2213.

I could not get the mids out, as they appear to be held in with some kind of tube. Clearly someone has been in there before as I see glue on the mid tube, and masking tape holding insulation to the bass port tube.

Tweets are marked LE25. The PO went a bit nuts on Mortite sealing strips. Does a ported speaker really need to be sealed?

Looks like crossovers have already been upgraded using a pair of 4uF Dayton film caps in parallel to make 8uF, and another Dayton cap that I could not read the value on. It also looks like they have bypass caps. Not sure why those would be added to a film cap.
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motorcityguy said:
Looks like crossovers have already been upgraded using a pair of 4uF Dayton film caps in parallel to make 8uF, and another Dayton cap that I could not read the value on. It also looks like they have bypass caps. Not sure why those would be there on a film cap.
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Many newer JBL crossovers utilize bypass caps so I suppose someone decided it was worth $1.50 (or whatever) for each bypass cap to add them. May not help but I doubt they could hurt.
 
donprice said:
Many newer JBL crossovers utilize bypass caps so I suppose someone decided it was worth $1.50 (or whatever) for each bypass cap to add them. May not help but I doubt they could hurt.
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I wish! I use AudioCap 0.01 mfd and they are $7.69 each. I piggyback these on Solen Fastcaps. :hug:
 
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