L-150s Restore and Recap

[Jobrewer1983]

Good Morning Lansing Folks,

Hope all of you had a great Christmas/New Years. I have been in the process of acquiring a pair of the L-150s for a few weeks now. Yesterday I was able to finally get my hands on them. My friend James is a huge collector of vintage gear, he wheels and deals all over California. A few weeks back he picked up a pair of L-150s in Los Angeles at a flea market for $50.00.

We have been going back and forth on what to swap for, or a price he would let them go for. He basically did not want to sell them to me, due to us constantly bartering for gear. The past few barters he has gotten the better end of the deals, and he wanted to give them to me. He knows I enjoy restoring vintage receivers/amps and asked me if I would mind trouble shooting a few receivers for him. I gave him the $50.00 he paid for them, and I am in the process of cleaning a Pioneer SX-880, and will be working on a Sansui AU 717 for him.

On to the good stuff:

I have not had the opportunity to remove any of the drivers yet, or check the crossovers, but I am wanting to recap the crossovers. While I have replaced caps before, it’s usually a trip to FRY’s or Radio Shack for cheap caps. I am looking for some good quality replacements, any suggestions? Has anyone on the site conducted a rebuild on the X-overs for the 150s? If so, any tips would be greatly appreciated. Any upgrades that any one is willing to share?

I will be sure to take many pictures, and post them along the way. I will be doing a steel wool rub, and a Danish oil finish. The cabinets are in great shape, even the raisers are still intact. The cabinets will not require much work.

Any information would be greatly appreciated, and as always, thank you in advance.

Thanks All,
John

[grumpy]

Those appear to be in fine shape other than the obvious surround issue... easily resolved. Fun speakers

I'd check the operation of the L-pads first. Consider updating the terminals. Then perhaps a small update
to the crossover (parallel .01uF mylar or polypropylene across the larger values as JBL themselves did
with the L150A/L112/L96 line). Then see how they sound before jumping in with larger changes.

[Doc Mark]

Good Morning, Jobrewer1983,

You got a wonderful deal on those L150's! I remember when they first came out, and I eagerly went to the local Hi-Fi stores to get some brochures on them! They looked great back then, and they still look great today! Good luck on your refurbishing job, and I'm looking forward to seeing your progress as you wend your way down that happy path. Take care, and God Bless!

Every Good Wish,
Doc

[rdgrimes]

There's a complete set of innards on eBay right now for the L150A. If I were re-doing a pair of L150, the upgrade to L150A would be high on the list of possibilities. IMHO, the 044 is a superior tweeter to the 033. You can also substitute crossovers from the L96 or L112 for the L150A.

[Jobrewer1983]

Those appear to be in fine shape other than the obvious surround issue... easily resolved. Fun speakers

I'd check the operation of the L-pads first. Consider updating the terminals. Then perhaps a small update
to the crossover (parallel .01uF mylar or polypropylene across the larger values as JBL themselves did
with the L150A/L112/L96 line). Then see how they sound before jumping in with larger changes.

Good Morning Grumpy,

Thank you for the information. I figured I would spray a little Deox-it in the L-pads, is it possible that they will need to be replaced? Do they hold a value that can be lost, or would a good cleaning do the job? As for the crossovers, I'm just worried that the high end has lost its value. I'm no expert, but I have noticed that when the caps go bad, the top range seems to not be so clear/sharp.

As for the terminals, I am planning on installing some banana plugs, I just found out that my brother in-law has a box full of high end connectors and cables for me. I was talking with him over the holiday, apparently a few years back he went in on purchasing a Magnolia show room floor when they were closing out a Best Buy in the local area. I was shocked to find this out, he said he has a garage full of parts for me. I just need to make the time to go pick them up. not sure what he has exactly, but i'm sure ill find something good..

Once I finish the foam job i'll have a better understanding of where I stand. I will be running them with my L -110A's, ill take a look at the L-150A crossover schematic to see what the difference is between the L-150 and L-150A.

Thank you for the great information!! Ill be sure to outline each step along the way via the thread.

[Jobrewer1983]

There's a complete set of innards on eBay right now for the L150A. If I were re-doing a pair of L150, the upgrade to L150A would be high on the list of possibilities. IMHO, the 044 is a superior tweeter to the 033. You can also substitute crossovers from the L96 or L112 for the L150A.

Good Morning rdgrimes,

I have not had the opportunity to test any of the 044 tweeters, this is only my 2nd pair of JBL's and my L-110A's have the 033's. Will the 044 tweeters fit the same cut out as the 033? I've read many times that the 044 is a lot better, but is it really going to make a noticeable difference to the ear?

Thank you for the information, If I go the 150A upgrade, I'm sure ill be asking many questions along the way.

[Jobrewer1983]

Good Morning, Jobrewer1983,

You got a wonderful deal on those L150's! I remember when they first came out, and I eagerly went to the local Hi-Fi stores to get some brochures on them! They looked great back then, and they still look great today! Good luck on your refurbishing job, and I'm looking forward to seeing your progress as you wend your way down that happy path. Take care, and God Bless!

Every Good Wish,
Doc

Good Morning Doc,

Thank you for the kind words, I would love to get my hands on some original literature. I agree, the deal I got is pretty amazing. Mind you I needed to downsize a few months back due to a lack of space in my living room, so my friend James got my University's from the early 60's in new cond. I was the 2nd owner, and the original kept them in the boxes... I did not have my rack finished at the time, and needed the space. It was either store them in our parking garage, or get rid of them. I could not think of anyone who would enjoy them as I did other then my friend James. He still has them, and loves them. If you look me up on AK you can see some of the many changes my system has gone through over the past year.. Its pretty impressive for what I have paid for everything. Mind you its been years of searching and swapping... Its a hobby that I cant kick. I added a few pix of the tops to show the cond.

Again, thank you for the post.

God Bless,
John

[rdgrimes]

Good Morning rdgrimes,

I have not had the opportunity to test any of the 044 tweeters, this is only my 2nd pair of JBL's and my L-110A's have the 033's. Will the 044 tweeters fit the same cut out as the 033? I've read many times that the 044 is a lot better, but is it really going to make a noticeable difference to the ear?

Thank you for the information, If I go the 150A upgrade, I'm sure ill be asking many questions along the way.

I have a lot of time with the 044, and some time with the 066 which is pretty similar to the 033. The 044 is virtually indestructible, and sounds better when pushed hard. The 033/066 sound worse when pushed, at least to my ear. The 044 is pretty much the pinnacle of the development curve for soft dome tweeters, they don't get any better. Everything else is the same in those 2 models, just the tweeter and crossover need to be obtained. (unless you want the shiny frame of the LE5-12.)

[audiomagnate]

Deoxit doesn't do anything for L-Pads in my experience. If they're bad it's usually because of overheating and they need to be replaced.

[Jobrewer1983]

I have a lot of time with the 044, and some time with the 066 which is pretty similar to the 033. The 044 is virtually indestructible, and sounds better when pushed hard. The 033/066 sound worse when pushed, at least to my ear. The 044 is pretty much the pinnacle of the development curve for soft dome tweeters, they don't get any better. Everything else is the same in those 2 models, just the tweeter and crossover need to be obtained. (unless you want the shiny frame of the LE5-12.)

Thanks rdgrimes,

Ill have to track down some o44s, eBay was a bust... Just checked. There is someone on CL who has some midrange drivers, they look like the LE5-2's but they look a little newer, they are the pro series, so I'm assuming they are mid 80's-early 90's. He is asking $90 per set, and he has 2 sets, the good thing is they have the silver face. Not sure if they are the LE5-2s or not, but if so I've read that they are a little better then the LE5-12's. Any input on the differences between the 2 and 12 other than the noticeable magnet, and the inverted dome? Both seem to run near a $bill on eBay and CL, I would like to pick the better of the two if there is a difference.

Link to drivers on CL: http://sfbay.craigslist.org/sfc/msg/4825531275.html

Ill keep my eyes open for the 044's, ill check bartertown tonight as well. Thank you for the good information!

[Jobrewer1983]

Deoxit doesn't do anything for L-Pads in my experience. If they're bad it's usually because of overheating and they need to be replaced.

Good Morning audiomagnate,

I did not know this, looks like I will be replacing them. Is there a better brand that I should go with, or would the local frys/ Radio shack have something suitable?

Thank you again for the information!

[Jobrewer1983]

Good Morning All,

It's been a while, I did not forget about the L-150's I wanted to knock out the Sansui 717 before I stated the JBLs. Nonetheless, I knocked out the Sansui yesterday.. See Link and video:

http://www.audiokarma.org/forums/sho...d.php?t=634612

I will be starting the L-150 in the next day or so, I am waiting for the foam to arrive! the video is on Page 6..

Thanks All,
John

[couldbfishin]

This is an old thread now, but maybe someone doing a similar search will read this.

I have a pair of L150s that don't sound as good as they once did. The woofers and midranges look good, one tweeter is pushed in and is not putting out sound. The other tweeter is very faint.

I have never recapped speakers before, so I am reading threads here and checking videos on YouTube. This thread was useful.

I have a simple question now. I see in the photos of the active woofer on these L150s that they are white. The woofers on my L150s are black. Does this mean anything?

I previously owned L150A's and the woofers were also white.

Do I have an early model pair of L150's or did they provide woofers in either color?

Just curious.

Thanks,

[BMWCCA]

This is an old thread now, but maybe someone doing a similar search will read this.

I have a pair of L150s that don't sound as good as they once did. The woofers and midranges look good, one tweeter is pushed in and is not putting out sound. The other tweeter is very faint.

I have never recapped speakers before, so I am reading threads here and checking videos on YouTube. This thread was useful.

I have a simple question now. I see in the photos of the active woofer on these L150s that they are white. The woofers on my L150s are black. Does this mean anything?

I previously owned L150A's and the woofers were also white.

Do I have an early model pair of L150's or did they provide woofers in either color?

Sounds like your L150s have been messed with! Non-functioning tweeter is commonly caused by dirty L-pads. Try working the controls back and forth several times with sound off or at very low volume, then try it again. The woofers, well, you'll have to provide us with some pictures to be sure but why not take out the active woofer and see what it is. If you're lucky, someone re-coned or replaced the 128H with a 128H-1 which is the same but with a black cone.

[couldbfishin]

Hi again,
I have some photos of my JBL L150s. They are sequential serial numbers, 17621 and 17622. They don't sound as good as they once did and I am thinking of recapping. It would be my first recap, so any good advice would be appreciated.

Also, I noticed in researching the L150 that the active 12" woofer in all photos I have seen has the white coating on the cones to make them stiffer. I read in a JBL brochure this is what the white material is. I am curious why my L150s don't have the white coated woofers.

Also, I would appreciate it if you would look at the midranges and the tweeters and tell me if I should attempt to pull the dents out or replace them. I have done it before on other speakers using tape. I am guessing it will work on the mid-range dustcovers, but I am not sure about dome tweeters.

Not to get too convoluted in this thread, but is it possible my problem is with my source rather than the speakers? I have tried multiple sources, three Marantz receivers 2275, 2285B and 2325, and McIntosh tube gear, C20 preamp and two MC-40 mono block amps. They are all pretty clean sounding gear, although none of them comes close to the 300 wpc max rating of the speakers.

I really think I need to do something with the speakers, and I am thinking recap. They are 37-40 years old.

What do you think?