JBL L Series (1990s)

[mortron]

No idea, I bought it this way. Most of my speaker knowledge comes from my car audio days. On ported enclosures, the port is almost always in close proximity to the driver due to size constraints.

In most speakers in car audio with a port, the driver is a 10+ inch woofer, by comparison, the port is rather small.

On the L5, the port looks to be about half the diameter of the 708 driver. Its somewhat behind the driver as well. This as I have read, can cause the woofer to act more like a free air woofer in a respect - the box does not damp the woofers excursion as much, and sub bass will overexert the woofer. The reason I am lead to believe this is that both of my 708 woofers had spider damage where they separate from the cone due to over exertion and degradation of the adhesive used.

That said... my woofers were still moving, and not cooked. Had I kept listening they would have been. But I stopped and took a step back, and called a pro.

While my diagnosis of torn seam between spider and cone was correct, there was something I didn't know about:

When a speaker bottoms out, the voice coil former will hit against the backing inside the basket and damage the former. This can cause coil material to unravel from the former, contacting the inside of the basket, causing additional rubbing beyond the cone and spider friction. This was what was going on in mine. The repair person dissected the original driver, inspected it, and rebuilt it with the original cone. Its impossible to tell which one he repaired, and even he had trouble identifying which one it is.

In my limited experience, and based on posts and videos I have seen, it would seem that the 708 suffers an early death if neglected, but can be brought back from the brink of certain death if one has the patience and means to go about it. It also helps to use professional repair people with real world experience working with JBL and other high end and vintage drivers.

[JBLAddict]

Setup the L1's to rock my daughters high school spirit night yesterday.
100W early 90's Kenwood integrated + L1 put out surprisingly filling open-air Disney theme toons
Good to see them faithfully serving the public 25 yrs later

[grumpy]

Nice. Wonder how many L1 systems were involved with budding students... I don't think I'm getting "mine" back

[JBLAddict]

Nice. Wonder how many L1 systems were involved with budding students... I don't think I'm getting "mine" back

Yup, my student already put a claim on these once he moves out......

[thymanst]

Resurrection time - picked up a pair of L7's off cl cheap - couple dings, but drivers are perfect. Read whole thread ( ok not all the measurement posts) placed 3' out from walls with. 15 Deg. toe in - great soundstage and bass - using Yamaha rxa3040 in bi-amp mode (150 both hf & lf) drives them well - home theater sounds great with them. Had L250s, l890's and they compare favorably. I'm a big soundstage guy and really appreciate the stage they throw.

bonus - I remembered I had a lc2 and a pair of l820 bookshelves so changing out my ht speakers to a JBL lineup

[JBLAddict]

Congrats, the L7 is still a fine performer. I have mine in storage after switching to the PT stacks a few years ago. Was at the storage unit a few weeks ago staring at them wondering if I should lug the beasts back home for some ear time. They have a power and presence I do miss sometimes, but the Performance series 5.1 is so well balanced around the room and easy to manage with flat PT800s wall mounted on the rears its hard to disrupt what is an ideal setup.

[JuniorJBL]

Resurrection time - picked up a pair of L7's off cl cheap - couple dings, but drivers are perfect. Read whole thread ( ok not all the measurement posts) placed 3' out from walls with. 15 Deg. toe in - great soundstage and bass - using Yamaha rxa3040 in bi-amp mode (150 both hf & lf) drives them well - home theater sounds great with them. Had L250s, l890's and they compare favorably. I'm a big soundstage guy and really appreciate the stage they throw.

bonus - I remembered I had a lc2 and a pair of l820 bookshelves so changing out my ht speakers to a JBL lineup

Congrats on the purchase!!

I am glad you are enjoying them! The L7's are quite fun IMO!

[Holtcamp]

I love the style on those old ones.

[AugustaPrime]

Hello all, I've recently got a pair of JBL L5s and after a couple months of use I was checking out the woofers. For whatever reason I touched the 5" midwoofer under the tweeter and noticed that I could not feel it move at all as music was playing. The low end woofers on the bottom were definitely moving and I could hear music coming out of the tweeter. It didn't sound like any music was coming out of the midrange woofer. I moved over to the other speaker and was shocked to find the same occurance, I couldn't feel the midrange woofer vibrating or moving at all as music was playing. Is the frequency as such that you can't feel the woofer moving or could it be a random case that BOTH woofers are busted or not connected? I have unscrewed them from the speaker to investigate the inside yet... I plan on doing that tonight. Thanks for any insight

[Chris Brown]

I touched the 5" midwoofer under the tweeter and noticed that I could not feel it move at all as music was playing.

The crossover frequencies for the L5 are 170Hz/900Hz/4kHz. That means the 5" Midrange is only handling frequencies between 900Hz and 4Khz. Those aren't frequencies that are going to produce much cone movement. Try playing some test tones within that frequency range and see what sort of output you get.

[BMWCCA]

It didn't sound like any music was coming out of the midrange woofer.

I find using the inner cardboard tube from a roll of paper towels held to the ear and in front of the suspect driver can often help determine if there's sound coming out . . . or not.

Welcome to the Forum. I have two pair of L5s and two pair of L7s if I can help with anything. So, how do they sound?

[AugustaPrime]

I find using the inner cardboard tube from a roll of paper towels held to the ear and in front of the suspect driver can often help determine if there's sound coming out . . . or not.

Welcome to the Forum. I have two pair of L5s and two pair of L7s if I can help with anything. So, how do they sound?

The crossover frequencies for the L5 are 170Hz/900Hz/4kHz. That means the 5" Midrange is only handling frequencies between 900Hz and 4Khz. Those aren't frequencies that are going to produce much cone movement. Try playing some test tones within that frequency range and see what sort of output you get.

Great ideas, thanks for the responses. The paper towel roll helped out a lot to isolate the woofer as the speaker was playing. It sounds like the woofer is working fine . The limited frequency range must be why there's not much woofer movement that alarmed me in the first place. The speakers have sounded great so I would've been really surprised if the midrange woofer was not operating at all! These speakers have been in my second system and on the back burner for awhile due to my new purchase of some Ascend RAAL towers, but with all the praise they get on here and elsewhere I need to give them a serious listening to.

[Slava Z.]

Meet a new member! Manage to get a pair of L7 from my boss. The price is 35 000 roubles (appr. 580 $). Previous speakers were Infinity Ref.61 MkII. Receiver Pioneer 922 for Home Cinema and Multichanel, Amp. Pioneer 702 for LP and Stereo. Unfortunately 10 years ago left unit of L7 was slightly damaged by a dog. The beast used it as a WC several times (((. In spite of this the rest is perfect. Will search for a cabinet (or a cabinet-maker) somewhere not far. Find one at Ebay. The unfortunate left unit is also spoilt.((( Besides the shipping is rather expensive. Decorate the wound by a flower for a while.The other thing. If I am not dealing with bi-amp and bi-wi, the manipulations with inner jumper is of no use for me ?
PS Read 40 pages.

[jkrichards]

Well I'm back on the L7 Group as I just picked up another pair after I sold my last pair and missed the sound. I now have a pair of USA made, a Japan Made, and a UK made monitors. The JBL's just have that kickin' bass and drive that no other has.





From left to right:
L7's, Yamaha NS-1000M, Bowers & Wilkins 802 Diamond.
Pick your flavor! They all sound good.

[BMWCCA]

Well I'm back on the L7 Group as I just picked up another pair after I sold my last pair and missed the sound. I now have a pair of USA made, a Japan Made, and a UK made monitors. The JBL's just have that kickin' bass and drive that no other has.

Welcome back. You have some nice choices of what to listen to.