JBL L100?

[beeker]

I should recant some of my previous reply about the studio jbl's. They have absolutely awsome drivers. Honestly compared to a large percentage of drivers ever produced the jbl l00 and derivitives cabinets are loaded with top notch drivers. I am knowlegable about my testing with meters and ears tests and dont write anything down although rememeber mostly what i hear with my ears. L100 and derivitives are around 90 sensitivity. I gotta repeat the drivers are just amazing and with a good crossover wow these could be some of the finest speakers around. My L166's have a titanium tweeter and very similar to the L100 and still the sound and sensitivity is about parallel. I am more a solid state user at the moment then again with testing the L100 and derivitives on tubes they pull good power for an audiophile and is clean but the crossover is really one of the most unimpressive in audio and listening results are interesting. It just dont make sense considering the amazing jbl/altec drivers, with a nice crossover all these vintage jbl studio derivitives would surely be supreme.

The main hurdle i cannot get over are the simple sensitivity specs compared to our klipsch at 95 and about. Even with my favorite speaker the klipsch kg.5 with a lower sensitivity with a descent powered bass driver I am ever so impressed with quality of sound. Bottom line those precious vintage jbl studio drivers and used with a proper network I see these jbl studio derivitives as very high end and well worth the money. Any i want to re-state my comment on aftermarket drivers because i know some are just as good if not better. I would just be careful to those people not sure to do homework on whats inside or out before spending the amounts these jbl monitors are selling for. I have mine in climate controlled storage and insured nonetheless. I really do not see myself selling anytime soon now that i can see there are locals here in the K forums with details i can have somebody build networks worthy enough to install in a cabinet with these good jbl drivers.

On my lower to mid quality tube amps i have to have at least 87db sensitivity to hold what i'd call respective, consistant audio levels and sound. With planars in particular as sweet as sound gets i prefer a speaker that can maintain these respective levels consistantly. If the speaker/monitor dont sound good on tubes to me i find it difficult to keep in use. I will change in time as things do yet at this moment in time i cannot get enough of the high sensitivity in the speakers i use. I have about 20 pairs of speakers in my primary audio room now with half as many amplifiers. With the size of the l100's they may find space in here with a good crossover when i have the money of course haha The K forum sure does get the mind gears turning always for the better. Thank you for letting me be a part of this . . .. .

[djk]

"My L166's have a titanium tweeter"

Every one I have seen has the 066, a phenolic diaphragm that has aluminium sputtered on it. The aluminium frequently flakes off, and they frequently rubbed, as did the 033 they were based on.

http://www.ebay.com/itm/Foam-Rings-for-JBL-LE25-Tweeters-Fits-L100-L25-L45-L71-L88-Speakers-1-Pair-/151004141548?pt=US_Speaker_Parts_Components&hash=item23288c57ec#ht_908wt_758

http://www.ebay.com/itm/261207613642?ssPageName=STRK:MEWAX:IT&_trksid=p3984.m1423.l2649#ht_63wt_1156

[Marvel]

...but the new crossovers will take care of that. The reports from users are very impressive. And with good drivers, you would expect good results once the crossover is right.

Mark,

Did you ever get these finished? I'm still curious what you think of the sound.

Bruce

[Marvel]

Thanks for the update, Mark. That's really encouraging. Is the schematic in Post #7 the one you built?

Bruce

[Marvel]

Mark,

Dragging this back to the top...

Have you ever tried plugging the ports on your L100s? Some of the folks on the Lansing Heritage site say the woofers really work better in a sealed box. I haven't built new crossovers yet but did buy some plumber's test plugs to use. These can be pulled back out with no permanent change to the cabinets. The bass seems a bit tighter and much deeper than my Heresy IIs.

Bruce

Edited August 5, 2014 by Marvel

[Swerd]

mdemeem

A friend recently told me about this thread, which I hadn't noticed before. I'm alway happy to hear about people who built this crossover, and I'm very glad to see how much you like it .

I originally wrote that thread about the new crossover for JBL L-100s, years ago, and posted it on the Audioholics forum http://forums.audioholics.com/forums/diy-corner-tips-techniques/25014-vintage-jbl-west-coast-sound-becomes-%85.html and later on the Lansing Heritage forum http://www.audioheritage.org/vbulletin/showthread.php?13105-New-crossover-design-for-L-100A

When I built these crossovers for my L-100s, I used no variable L-pads in them. The balance among the three drivers is done correctly (in my opinion) by crossover, and those variable L-pads develop such oxidation that that, new or old, they all become noisy.

Someone commented that the new crossovers lower the sensitivity by 5 dB. That was my original guess, but more carefull measurments showed it was in the range of 1 to 3 dB depending on the frequency. The loss was small enough to not be a problem.

Someone else had commented that the "3.9µF in parallel with the tweeter doesn't look quite right."

A cap going directly to ground (see the 3.9 µF cap on the tweeter circuit) should, in theory, be avoided because it might create a significant impedance dip at high frequencies. In practice it was fine and caused no trouble. See the attached impedance plot. The tweeter impedance is the green line, and the total impedance is the black line.

[Swerd]

mdemeem

A friend recently told me about this thread, which I hadn't noticed before. I'm alway happy to hear about people who built this crossover, and I'm very glad to see how much you like it .

I originally wrote that thread about the new crossover for JBL L-100s, years ago, and posted it on the Audioholics forum http://forums.audioholics.com/forums/diy-corner-tips-techniques/25014-vintage-jbl-west-coast-sound-becomes-%85.html and later on the Lansing Heritage forum http://www.audioheritage.org/vbulletin/showthread.php?13105-New-crossover-design-for-L-100A

When I built these crossovers for my L-100s, I used no variable L-pads in them. The balance among the three drivers is done correctly (in my opinion) by crossover, and those variable L-pads develop such oxidation that that, new or old, they all become noisy.

Someone commented that the new crossovers lower the sensitivity by 5 dB. That was my original guess, but more carefull measurments showed it was in the range of 1 to 3 dB depending on the frequency. The loss was small enough to not be a problem.

Someone else had commented that the "3.9µF in parallel with the tweeter doesn't look quite right."

A cap going directly to ground (see the 3.9 µF cap on the tweeter circuit) should, in theory, be avoided because it might create a significant impedance dip at high frequencies. In practice it was fine and caused no trouble. See the attached impedance plot. The tweeter impedance is the green line, and the total impedance is the black line.

[Swerd]

mdemeem

A friend recently told me about this thread, which I hadn't noticed before. I'm alway happy to hear people who built this crossover and I'm very glad to see how much you like it .

I originally wrote that thread about the new crossover for JBL L-100s, years ago, and posted it on the Audioholics forum http://forums.audioholics.com/forums/diy-corner-tips-techniques/25014-vintage-jbl-west-coast-sound-becomes-%85.html and later on the Lansing Heritage forum http://www.audioheritage.org/vbulletin/showthread.php?13105-New-crossover-design-for-L-100A

When I built these crossovers for my L-100s, I used no variable L-pads in them. The balance among the three drivers is done correctly (in my opinion) by crossover, and those variable L-pads develop such oxidation that that, new or old, they all become noisy.

Someone commented that the new crossovers lower the sensitivity by 5 dB. That was my original guess, but more carefull measurments showed it was in the range of 1 to 3 dB depending on the frequency. The loss was small enough to not be a problem.

Someone else had commented that the "3.9µF in parallel with the tweeter doesn't look quite right."

A cap going directly to ground (see the 3.9 µF cap on the tweeter circuit) should, in theory, be avoided because it might create a significant impedance dip at high frequencies. In practice it was fine and caused no trouble. See the attached impedance plot. The tweeter impedance is the green line, and the total impedance is the black line.

[Swerd]

mdemeem

A friend recently told me about this thread, which I hadn't noticed before. I'm alway happy to hear people who built this crossover and I'm very glad to see how much you like it .

I originally wrote that thread about the new crossover for JBL L-100s, years ago, and posted it on the Audioholics forum http://forums.audioholics.com/forums/diy-corner-tips-techniques/25014-vintage-jbl-west-coast-sound-becomes-%85.html and later on the Lansing Heritage forum http://www.audioheritage.org/vbulletin/showthread.php?13105-New-crossover-design-for-L-100A

When I built these crossovers for my L-100s, I used no variable L-pads in them. The balance among the three drivers is done correctly (in my opinion) by crossover, and those variable L-pads develop such oxidation that that, new or old, they all become noisy.

Someone commented that the new crossovers lower the sensitivity by 5 dB. That was my original guess, but more carefull measurments showed it was in the range of 1 to 3 dB depending on the frequency. The loss was small enough to not be a problem.

Someone else had commented that the "3.9µF in parallel with the tweeter doesn't look quite right."

A cap going directly to ground (see the 3.9 µF cap on the tweeter circuit) should, in theory, be avoided because it might create a significant impedance dip at high frequencies. In practice it was fine and caused no trouble.

I'm trying to attach an impedance plot to illustrate this, but I can't seem to do it.

[Swerd]

mdemeem

A friend recently told me about this thread, which I hadn't noticed before. I'm alway happy to hear people who built this crossover and I'm very glad to see how much you like it .

I originally wrote that thread about the new crossover for JBL L-100s, years ago, and posted it on the Audioholics forum http://forums.audioholics.com/forums/diy-corner-tips-techniques/25014-vintage-jbl-west-coast-sound-becomes-%85.html and later on the Lansing Heritage forum http://www.audioheritage.org/vbulletin/showthread.php?13105-New-crossover-design-for-L-100A

When I built these crossovers for my L-100s, I used no variable L-pads in them. The balance among the three drivers is done correctly (in my opinion) by crossover, and those variable L-pads develop such oxidation that that, new or old, they all become noisy.

Someone commented that the new crossovers lower the sensitivity by 5 dB. That was my original guess, but more carefull measurments showed it was in the range of 1 to 3 dB depending on the frequency. The loss was small enough to not be a problem.

Someone else had commented that the "3.9µF in parallel with the tweeter doesn't look quite right."

A cap going directly to ground (see the 3.9 µF cap on the tweeter circuit) should, in theory, be avoided because it might create a significant impedance dip at high frequencies. In practice it was fine and caused no trouble. See the attached impedance plot. The tweeter impedance is the green line, and the total impedance is the black line.

[Swerd]

mdemeem

A friend recently told me about this thread, which I hadn't noticed before. I'm alway happy to hear people who built this crossover and I'm very glad to see how much you like it .

I originally wrote that thread about the new crossover for JBL L-100s, years ago, and posted it on the Audioholics forum http://forums.audioholics.com/forums/diy-corner-tips-techniques/25014-vintage-jbl-west-coast-sound-becomes-%85.html and later on the Lansing Heritage forum http://www.audioheritage.org/vbulletin/showthread.php?13105-New-crossover-design-for-L-100A

When I built these crossovers for my L-100s, I used no variable L-pads in them. The balance among the three drivers is done correctly (in my opinion) by crossover, and those variable L-pads develop such oxidation that that, new or old, they all become noisy.

Someone commented that the new crossovers lower the sensitivity by 5 dB. That was my original guess, but more carefull measurments showed it was in the range of 1 to 3 dB depending on the frequency. The loss was small enough to not be a problem.

Someone else had commented that the "3.9µF in parallel with the tweeter doesn't look quite right."

A cap going directly to ground (see the 3.9 µF cap on the tweeter circuit) should, in theory, be avoided because it might create a significant impedance dip at high frequencies. In practice it was fine and caused no trouble. See the attached impedance plot.

I've tried to attach an impedance plot to illustrate this, but I'm having difficulty doing it.

[Swerd]

mdemeem

A friend recently told me about this thread, which I hadn't noticed before. I'm alway happy to hear people who built this crossover and I'm very glad to see how much you like it .

I originally wrote that thread about the new crossover for JBL L-100s, years ago, and posted it on the Audioholics forum http://forums.audioholics.com/forums/diy-corner-tips-techniques/25014-vintage-jbl-west-coast-sound-becomes-%85.html and later on the Lansing Heritage forum http://www.audioheritage.org/vbulletin/showthread.php?13105-New-crossover-design-for-L-100A

When I built these crossovers for my L-100s, I used no variable L-pads in them. The balance among the three drivers is done correctly (in my opinion) by crossover, and those variable L-pads develop such oxidation that that, new or old, they all become noisy.

Someone commented that the new crossovers lower the sensitivity by 5 dB. That was my original guess, but more carefull measurments showed it was in the range of 1 to 3 dB depending on the frequency. The loss was small enough to not be a problem.

Someone else had commented that the "3.9µF in parallel with the tweeter doesn't look quite right."

A cap going directly to ground (see the 3.9 µF cap on the tweeter circuit) should, in theory, be avoided because it might create a significant impedance dip at high frequencies. In practice it was fine and caused no trouble. See the attached impedance plot. The tweeter impedance is the green line, and the total impedance is the black line.