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fini
04-01-2016, 04:09 PM
Hi folks! It only took me 10 years, but I'm back! ;)

The other day, I was very surprised to run into a pair of 4315 Studio Monitors at a second-hand store. Unfortunately, they're not in the best shape, and I'm considering my options. My first choice would be restoration. First, the enclosures. One is in reasonable shape, in need of a re-veneer job. The other enclosure most certainly had a bad encounter with moisture. I'm pretty sure I would need to replace each side panel, as well as the top and bottom. This concerns me, as I know these aren't just simple boxes.

Secondly, they both have fallen victim to foam rot. In searching the forum here, I've seen that the refoam kits for both the 2203 and 2108 are no longer available. These were threads from a few years back, and I see that several kits are available on eBay. What are the current thoughts on the repairability of these components?

I'd hate to cannibalize these beasts for parts. I'd love to hear them!

Challenger604
04-01-2016, 05:11 PM
Hi folks! It only took me 10 years, but I'm back! ;)

The other day, I was very surprised to run into a pair of 4315 Studio Monitors at a second-hand store. Unfortunately, they're not in the best shape, and I'm considering my options. My first choice would be restoration. First, the enclosures. One is in reasonable shape, in need of a re-veneer job. The other enclosure most certainly had a bad encounter with moisture. I'm pretty sure I would need to replace each side panel, as well as the top and bottom. This concerns me, as I know these aren't just simple boxes.

Secondly, they both have fallen victim to foam rot. In searching the forum here, I've seen that the refoam kits for both the 2203 and 2108 are no longer available. These were threads from a few years back, and I see that several kits are available on eBay. What are the current thoughts on the repairability of these components?

I'd hate to cannibalize these beasts for parts. I'd love to hear them!


Yes! It's possible!
With a lot of patience, you can bring those speakers back to life!
I would...
C

kelossus
04-01-2016, 05:25 PM
Hopefully the 2108's and 2203's just need a refoam and nothing more serious.

I have had 2 pair's of 4315's and one set was in similar condition.

You can strip the veneer and route the corners out so you can inlay a piece of inch by inch timber (or larger) in to give you square corners again and hold them together. Bog up any imperfections then reveneer. Time consuming but worth it.

Or you could just bin the cabinets (sacrilege), refoam the drivers you have and sell them for a profit. The 2108s and 2203s are rare as hen's teeth and the 2405's are still worth money.

I spent a long time trying to get the best out of the 4315's and unfortunately without heavy eq they are not easy listening. Stretching the 2105 all the way to 8k results in an extremely peaky speaker with excessive sibilance.

My 4315B's have ended up being a source of spare parts for my other speakers. Built a pair of 2203 stereo subs for my L212's, the 2405's in my L200's, the 2108's and 2105's are spares for my L212's.

Triumph Don
04-01-2016, 05:44 PM
JBL never offered foam kits, just complete recone kits. You want foam kits from this guy, they are the best.


http://stores.ebay.com/looneytune2001?_dmd=1&_nkw=jbl

How much are they asking for the speakers?

Challenger604
04-01-2016, 06:36 PM
Hi folks! It only took me 10 years, but I'm back! ;)

The other day, I was very surprised to run into a pair of 4315 Studio Monitors at a second-hand store. Unfortunately, they're not in the best shape, and I'm considering my options. My first choice would be restoration. First, the enclosures. One is in reasonable shape, in need of a re-veneer job. The other enclosure most certainly had a bad encounter with moisture. I'm pretty sure I would need to replace each side panel, as well as the top and bottom. This concerns me, as I know these aren't just simple boxes.

Secondly, they both have fallen victim to foam rot. In searching the forum here, I've seen that the refoam kits for both the 2203 and 2108 are no longer available. These were threads from a few years back, and I see that several kits are available on eBay. What are the current thoughts on the repairability of these components?

I'd hate to cannibalize these beasts for parts. I'd love to hear them!

Are you in Noth Bay Ontario?

fini
04-01-2016, 07:32 PM
JBL never offered foam kits, just complete recone kits. You want foam kits from this guy, they are the best.


http://stores.ebay.com/looneytune2001?_dmd=1&_nkw=jbl

How much are they asking for the speakers?

Don, I already purchased them. It was an amazingly low price!!

fini
04-01-2016, 07:33 PM
Are you in Noth Bay Ontario?

No, I'm in Northern California.

fini
04-01-2016, 07:41 PM
[QUOTE=kelossus;389269]Hopefully the 2108's and 2203's just need a refoam and nothing more serious.

kelossus, is there a way to test whether or not a refoam kit will restore the components before purchase and install?

Thanks everyone for the great responses!!

Challenger604
04-01-2016, 08:12 PM
If would call Simply Speaker and ask I'm sure they have something. They are very good and I'm sure they can help you.
You can plug them up to an amp and play very low volume. If you have a sound, you'll be ok with it...
Good luck!
C

kelossus
04-01-2016, 09:47 PM
Test the DCR on the binding posts with a multimeter do see if the coils are toast, that would be a start.

Wait for others to chime in regarding this but I would also have a go moving the cone to see if it is frozen or not. As the foam is deteriorated it may scrape as the coil is not aligned. I have tested speakers this way before but others may advise against this.

kelossus
04-01-2016, 09:49 PM
Also take the woofers out and have a look at the spiders.....have they sunk.....are the coils popping out??

mech986
04-02-2016, 05:56 AM
Hey Fini, congratulations and welcome back! Uh, that Avatar is hard to be unseen!

You obviously are quite lucky to find these, congrats! The folks above have already given you some good advice.

These are the 4315A's, and should have the all alnico drivers with the updated 3114A crossover and single port cabinets. Would suggest connecting the speakers up to a modest amplifier, then lay the speakers on their backs and playing them gently with low signal volume to see if they are all operational. You can use a typical paper towel roll center tube to focus your hearing on each driver to hear if its playing. Resist the idea of playing them any louder because you can damage the voice coils if the speakers are upright or played at high volume without good surrounds, and the 2203A woofer and 2018 bass-mid are the unique and tough to find drivers here.

Alternatively, as mentioned, you can remove the drivers (careful with any screwdriver), and check each one's voice coil for DC resistance with a multimeter, then check with light cone movement for smooth easy movement with no scratching or rub, assuming the cone is not tilted. If there is always a rub no matter what orientation you try, then the voice coil is suspect. You could then try playing some low volume music in each woofer and bass-mid. For the upper midrange, you need to cut the bass out completely from your signal, and do the same for the tweeter but play at lower volume settings.

As for the cabinets, I agree with the above, for the upper seam split, you'll likely have to consider cutting out a square profile section, cut, place and glue/clamp in a new square piece, and then reveneer. It looks too split to consider cleaning out and reglue and clamp hard. The bottom water damage needs more pictures to tell if there's anything salvageable, or your being better off contemplating taking off the entire bottom panel and parts of the side panels and fabricating a matching new section, gluing them in, and then reveneer. As such, you are likely to veneer both anyway as you mentioned the other needs it too, although I suspect the veneer has some nice patina and could be restored somewhat.

Of course, you'll want to go through the cabinets, crossover, controls, etc. and clean all that up, and update some stuff. Should be a fun project.

You might want to come over to Audiokarma.org as well, and start a similar thread in Speakers forum. Lots of enthused JBL folks there too, and both LH and AK have members in the SF Bay area who may be able to assist you with the cabinet work. MrBiggles in Richmond is one I'm familiar with on AK.

As for the refoams, you could contact Audiovex in Berkeley, supposedly good work, not always quickly though. Or in Santa Rosa, Sound Expressions, may be able to help you. Check with both for pricing and if they have the correct foams for the job, otherwise, get the foams from Rick Cobb in Florida, and have one or the other shop install them for you.

mech986
04-02-2016, 06:05 AM
If you found these near Rohnert Park, I wonder if they might have belonged to a late Lansing Heritage member who lived there? I also had a dear friend who lived there too who passed away middle of last year.

http://www.audioheritage.org/vbulletin/showthread.php?25530-JOHNAEC-s-Funeral-and-Memorial-Service&highlight=rohnert

gasfan
04-02-2016, 10:12 AM
[QUOTE=kelossus;389269]Hopefully the 2108's and 2203's just need a refoam and nothing more serious.

kelossus, is there a way to test whether or not a refoam kit will restore the components before purchase and install?

Thanks everyone for the great responses!!

DO NOT buy your 2203 foams from Simply Speakers. I just recently purchased some from there as I also have a pair of 2203. Their product is way too heavy, thick, and non-compliant. They are not correct. I re-ordered a pair from Rick Cobb, a member here who uses the moniker loony tunes on ebay or you can look him up here. I've received them and they are half the weight, thinner and much more compliant. Nothing against SS. I've bought from them numerous times with no issue, but these are just wrong.

Challenger604
04-02-2016, 10:42 AM
[QUOTE=fini;389279]

DO NOT buy your 2203 foams from Simply Speakers. I just recently purchased some from there as I also have a pair of 2203. Their product is way too heavy, thick, and non-compliant. They are not correct. I re-ordered a pair from Rick Cobb, a member here who uses the moniker loony tunes on ebay or you can look him up here. I've received them and they are half the weight, thinner and much more compliant. Nothing against SS. I've bought from them numerous times with no issue, but these are just wrong.

Did you let them know?

gasfan
04-02-2016, 10:48 AM
[QUOTE=gasfan;389319]

Did you let them know?

I did not. But I will forthwith.

Challenger604
04-02-2016, 11:49 AM
[QUOTE=Challenger604;389321]

I did not. But I will forthwith.

I went to see them in St Petersburg and they are very nice. I always had a good experience with them...
But once again it's just me...
C

Wagner
04-02-2016, 04:53 PM
[QUOTE=gasfan;389322]

I went to see them in St Petersburg and they are very nice. I always had a good experience with them...
But once again it's just me...
C
Simply Speakers sells over priced "close enough" generic crap
(I say this after HOURS pursuing these things and figuring out how they're manufactured sourced and supplied)

I just this past year went round and round with them over a hard to fit EV project
I know I contacted 25 people looking for this exact surround if I contacted one

Contacted Rick initially and he didn't show a listing so I went hunting, even posted here looking for a supplier
EV can no longer supply................long story, fairly rare pro 12" with a foam surround and not their usual pleated type

Wound up (back) where I should have stayed all along, with Rick Cobb (but I had to give it a try)
With his help and looking at a lot of measurements, I managed to secure a pair that were 98.9% correct, only the roll width is a wee bit on the light side, but more importantly didn't ADD an extra 1/4" of material on the cone (the MOST critical I.D.) to which Simply Speakers could only comment "we've used these lots of times with no complaints"

They copped attitude about it, that I wouldn't just play along and bow down to their great expertise

Just watch their "how to" videos and you will see I am not exaggerating the fact; they are turn and burn hacks

Thomas

Wagner
04-02-2016, 04:56 PM
No, I'm in Northern California.
Can you tell me where you found them? I am in Clayton

Nice score!

Thomas

fini
04-02-2016, 05:39 PM
Can you tell me where you found them? I am in Clayton

Nice score!

Thomas

Clayton,

They were discovered in Petaluma. My home town!

Gregg

Wagner
04-02-2016, 09:18 PM
Clayton,

They were discovered in Petaluma. My home town!

Gregg
A thrift, a "re-purpose" "gently used" "previously loved" or a consignment type shop?
I am only curious as the thrifts here in and around the East Bay have really fallen off as of late
Used to be a nice find of some sort with every trip (a lot of that ended with the easy, pre-2008 re-fi money drying up)
Congratulations on your find (and you know I am dying to know what you paid)
Thomas

Challenger604
04-02-2016, 11:22 PM
A thrift, a "re-purpose" "gently used" "previously loved" or a consignment type shop?
I am only curious as the thrifts here in and around the East Bay have really fallen off as of late
Used to be a nice find of some sort with every trip (a lot of that ended with the easy, pre-2008 re-fi money drying up)
Congratulations on your find (and you know I am dying to know what you paid)
Thomas

So do I!! LOL!

fini
04-03-2016, 11:49 AM
Clayton,

They were discovered in Petaluma. My home town!

Gregg

Oops, I meant Thomas!:crying: