Cosmetic restoration of vintage JBL L-100 Century speaker

Рет қаралды 51,503

3 жыл бұрын

My friend has lend me a pair of vintage JBL L-100 Century's for restoration.
They work just fine, but they has seen some abuse, so in this video I restore them back to their former glory. Nothing too special, just a cosmetic overhaul including:
► Sanding
► veneer repair
► Painting and oiling the cabinets
► Repainting the woofer driver
The JBL L-100 Century is the consumer version of the 4310 - the smallest speaker in the legendary 43XX range from JBL, known for their blue front and American walnut veneer. Because of the huge success and demand, the JBL L-100 Century's are maybe one of the most well-known vintage speakers today. Through the years I've restored and repaired quite a lot of them, but this time I'll take you along for the ride.
For an overview of the speaker and the different versions, please see the article I've written on auditur.dk/jbl-l-100-speakers...
Also, please like and subscribe for future projects!

Пікірлер: 107

@robertyoung1777 3 жыл бұрын

I would not take the risk of painting the woofers. It’s a golden rule of conservation to avoid doing anything that can’t be undone. Painting could change the sound characteristics of the loudspeaker. First do no harm.

@SorenKoelbaek 2 жыл бұрын

Thank you Robert - It is an individual choice. I would like to show in this video that it is possible. From my experience, and measurements and discussions withn JBL techs, the procedure does not alter the characteristics of the loudspeaker in any audible way. That being said I only do it as a measure in restoring a damaged woofer cone that would otherwise be replaced for cosmetic reasons alone. I agree with you in conservation you are very conservative in the chosen measures, but as you can see from the video this is not a conservation video, but a showcase of the different measures you can take to achieve a specific visual condition to your speakers. I am not saying you should, that is up to you - but I am showing what you could do.

@Reachowt Жыл бұрын

@@SorenKoelbaek What you should say more exactly is that "this video will showcase what you can do to cosmetically improve your JBL-100's(no matter which of the three). Each featured improvement is visual and will enhance the looks without compromising sound. Sound will not be compromised when painting the woofers(provide some JBL reference that goes beyond your own words). Not to correct you - but I agree that these Century L-100's look better and I wondered if painting the woofers is safe(i.e.; does not alter the performance and characteristic of the woofer). I was fortunate to be given a pair of Century L-100's a few years ago by a gentlemen in N.Carolina. They are visually very nice, but need tweeter foams and probably the crossover upgrade? I am no expert. Thank you and thanks for providing other L-100 information!

@SorenKoelbaek Жыл бұрын

@@Reachowt Thanks Phil! And thank you for your feedback, it is much appreciated. In regards to the crossover update please note that 1. the capacitors used by JBL are not prone to degradation over time. 2. They use values that are no longer standard values. 3. it is hard to access the crossover board without damaging the foilcal. I have done 3 different routes in the past, leaves as is, replace capacitors with new "audiophile types" and 3. doing the Troels Gravesen update. My experience is that the first two sounded identical, and the last changed the sonic characteristic in a huge way. some might find that "better" for me it was too different and I reverted back to the original filter. Congrats on the speakers!

@Reachowt Жыл бұрын

@@SorenKoelbaek Thank you for the detailed reply. I'm impressed, with all you have done with the L-100's. I read the same about the Troils Gravesen update and wondered just whether it was worth it. I think I'll leave mine as is-they sound good to me. Besides, I have older ears now-how much of a change would I really notice?. My speakers were originally in a large house in North Carolina, placed on built in shelving(no stands). I may just build some wood stands. Anyway-thank you for your comments, it has helped me decide.

@celticwoodworking8706 Жыл бұрын

During the 70's and early eighty's I was a professional musician. Every studio I walked into had a least one pair of 4310 JBL speakers for the engineer monitors. I always smile when people talk about the music is " supposed to sound" , because unless your standing in that room listening to the final mix, you will never know. The 4310 has always been my go to speaker for reference when it comes to rock music. Music is subjective and whatever sounds good to you is the right speaker. Thank you, as this was a wonderful walk through some great memories. Well done video work as well.

@SorenKoelbaek Жыл бұрын

I do like them, however it does has it's own sound, and there are bigger and better studio monitors that are more revealing, but it's a double edged sword. The L-100 was very widely used, alongside the Altec / Urei Coaxial monitors or the bigger 43XX series. The L-100 was often times used as a way to say "this is probably how it would sound at someones home" - where the other monitors where used for mixing and are "too" reveaeling. But that is the reason I have a set of 4343's as well :)

@buckaroo8805 3 жыл бұрын

They look really good Soren! Those speakers have been voted on a few lists to be the greatest speakers of all time!

@SorenKoelbaek 3 жыл бұрын

Thank you! They are great! which is probably why I’ve had many pairs - but the 4343 is quite a different league ;)

@KillerKlipsch Жыл бұрын

The Danes, they just cant help themselves, perfection is a way of life.

@theonlywaytofly 2 жыл бұрын

Hey, I really dig the Tuborg speaker stands. Very cool indeed!

@bikdav 3 жыл бұрын

I LIKE how you filled that hole on the back.

@geraldobrandi8280 Жыл бұрын

Belo serviço! Essas L100 são fantásticas! Som de qualidade muito acima do normal em um projeto muito simples! Parabéns por cuidar e salvar mais um par dessas preciosidades!

@PerfDayToday 3 жыл бұрын

Great work, nice video.

@SorenKoelbaek 3 жыл бұрын

Thanks David! - means a lot

@ianmartins Жыл бұрын

Great video, I recently scored a pair of JBL L112’s in rough cosmetic shape, but they sound great. I was contemplating painting the woofers as the old glue looks awful… interesting reading your earlier comment re speaking with JBl techs re:sound after painting. Might give it a go myself.

@stairwaytomusic71 Ай бұрын

Thanks for uploading it, beautifully done. BUT, as few people said about the painting on woofer, I would recommend to use Aquaplas to restore. All the best.

@SorenKoelbaek Ай бұрын

Aquaplas is the right material however, it is not possible to source as a a material (or very, very hard). When i researched and made enquiries last time, it came by the barrel, only in grey and had a shelf-life of 6 months. It is a rebrand of a material devised and sold as a structural paint used in large ships for acoustical control in engine rooms, apparantly. Also, I do not know if you can repair with Aquaplas - I would think you would have to have a raw paper-cone to give it an equal treatment.

@trihuynh5766 3 жыл бұрын

Good job brother. Thanks

@SorenKoelbaek 2 жыл бұрын

My pleasure

@reids_relics 2 жыл бұрын

Beautiful 4343’s

@SorenKoelbaek 2 жыл бұрын

thank you very much! I am very happy that I own a pair, and I really like the sound

@AudioElectronicsChicago 7 ай бұрын

Awesome

@steveogee7458 2 ай бұрын

Painting the woofers the correct way only increases the cone mass less than .05%. It's an Aquaplas coated cone. Do it.

@wilhamcobly3805 Жыл бұрын

wrong method for repaint woofers, sorry - first of all you used too much paint, making the cone heavier and it will no longer respond to its original characteristics, then you left out some points in the masking, and it shows. Thirdly, the aquaplas woofers have a yellowed edge which gives them an original feature, it is the glue used to fix the pleated edge - in my opinion, if not too yellowed or scratched, the aquaplas cones should not be touched - I have had many pairs of 4310 - 4311 - 4312 - only on one occasion have I used water-based, acrylic paint, VERY diluted and with a small roller, blending in the border, in order to "refresh" the white but leaving the glue border yellowed - I assure you it is much better, especially below the sound profile

@aliaqeeli3632 2 жыл бұрын

Nice work , Nice and perfect job, you made it look new. Looks great. Thank you for this video ❤️❤️

@SorenKoelbaek 2 жыл бұрын

My pleasure 😊

@alvaroriascos3004 Жыл бұрын

I have some PIONEER HPM 100 and I want to restore both their cabinets and their Driver cones. What do you suggest for the woofer cones? Thanks from Colombia.

@rayinpau.s.a.6351 2 жыл бұрын

Excellent Video ! , I have owned several pairs of these and always loved the powerful drive of them . I am always on the hunt for a pair of JBL's .

@SorenKoelbaek 2 жыл бұрын

Thanks for sharing!

@Arisild 3 жыл бұрын

awesome video Søren! I thought that the hole on the back is for the cabinet to take air? (what was the purpose of the hole ?)

@SorenKoelbaek 3 жыл бұрын

I can only speculate for why the hole was added by a previous owner. For airflow in a "ported box" the port is precisely calculated in terms of length, shape, diameter and placement, and the port is on the front. I could think the hole is for biamping the model, but coupling another amplifier directly on the bass-driver... But I can't verify that. It is not a pretty mod, and it compromises the seal of the cabinets, so a plug was in order ;)

@robwakefield5958 2 жыл бұрын

Can you tell me what paint you used please as I have also seen online not too paint the woofers, tks

@boandersen2895 2 жыл бұрын

I have L220s. There are a lot of small veneer chips on the bottoms. What kind of walnut veneer did JBL use, please? I see a LOT of different colored walnut veneers. And I have some walnut boards here and they look more gray? Or would you just use wood filler? Regards, Bo

@SorenKoelbaek 2 жыл бұрын

Hi Bo Thank you for asking, JBL used American Walnut veneer. The veneer has a grey tint before getting oil, so I wouldn't be afraid. If you need some inputs on filling veneer chips, you can also see the post I made on vintagehifi.dk Google: "JBL L-100 Century - Reborn III"

@SorenKoelbaek 2 жыл бұрын

Also - the 220's are nice speakers! I am a bit envious!

@donzash 2 жыл бұрын

Hey Soren, lovely video. How many coats of oil did you use?

@SorenKoelbaek 2 жыл бұрын

Just one - "soak it" and wait for the wood to not be able to take anymore and then wipe off excess :)

@user-pe1fb5uz6o 3 жыл бұрын

Молодец!!!!

@richardhuston2426 Жыл бұрын

The L-100’s are not notorious, they’re famous. Big difference. I own 4 that I bought in 1978, all still mint condition.

@spvlinn9009 3 жыл бұрын

Looks great! What brand of black spray and linseed oil used?

@SorenKoelbaek 3 жыл бұрын

The Black spray is an ordinary 9005 matte black - I would go for a quality manufacture (I didn’t but I had a ton of cheap cans lying around) The linseed again is just normal boiled linseed oil - purity is key here, but the product is the same no matter the manufacture - the one I used was bought in a paint-specialty shop, made for oil painting, and was much more expensive than the same product found in the hardware store.

@spvlinn9009 3 жыл бұрын

@@SorenKoelbaek many thanks!

@ScootieXP 2 күн бұрын

@@SorenKoelbaek The lindseed oil was already boiled in the bottle or you boiled? I found some linseed oil on the national market but doesnt say anything about being boiled and also needs like 24 hours to dry.

@origtex 3 жыл бұрын

I was hoping to see how you got the woofers out

@SorenKoelbaek 3 жыл бұрын

it is a bit tricky - my normal method is shown in another video - I take a screwdriver and via the mountinghole in the driver, i can shift it to the side to get it stuck in the metal hole of the woofer basket so I can pull the woofer out. hard to explain though - But be careful of wood and the nut mounted in the cabinet.

@bobbyserchion 3 жыл бұрын

Hi man can you give a link on were I can buy a pair of JBL speakers L100 or L65

@SorenKoelbaek 3 жыл бұрын

Hi Bobby - as these are vintage speakers that are no longer produced, you'll have to buy second-hand - there is not store where you can buy these. Depending on where you are there might be good local listing sites or services, otherwise take a look at Ebay, Craigslist or ask around on online-forums like Audiokarma and Lansingheritage. You can also try to take a look at hifishark.com, which indexes online sites.

@studio70audio 2 жыл бұрын

Repaiting the woofers? no, no, no...

@JessHull 3 жыл бұрын

what type of sand paper did you use? also what type of paint? you did a fantastic job, I have some L100's I'd like to give a soft restore.

@SorenKoelbaek 3 жыл бұрын

Thank you very much! Normal sandpaper, start with 180 or 240 with the grain and finish with 320 - you don’t want a polished feel on the veneer, it makes it look like plastic, so 320 is the highest. always with the grain, and use a block - for the matte black fronts I finished on grit 800, sanding in orbits so the finish is nice and smooth - painted with RAL 9005 matte black, the white in the woofers where montana gold eggshell primer :)

@JessHull 3 жыл бұрын

@@SorenKoelbaek this is great! thanks so much!

@JessHull 3 жыл бұрын

@@SorenKoelbaek I've started my soft restore using the techniques you've outlined in your video and so far so good!

@SorenKoelbaek 3 жыл бұрын

@@JessHull Good to hear!

@CarloRanieriRanieriracing 2 жыл бұрын

@@SorenKoelbaek why did you used only primer to paint woofers?

@williamjverhagen Жыл бұрын

What brand black spray paint. Was it Matt finish?

@williamjverhagen 5 ай бұрын

9005 matte black

@filipfilipovic1566 2 жыл бұрын

Curious why didnt you sand the front/back but rather just filled and sprayed them?

@SorenKoelbaek 2 жыл бұрын

Hi Filip - The filler was just meant to fill cracks and even out the surface for the paint. There was no real need to sand the front and back down completely as long as the surface was smooth. As you can see I did sand the filler and surrounding area to even it out :)

@R.A2030 3 жыл бұрын

painting paper drivers won't affect the sound?

@SorenKoelbaek 3 жыл бұрын

Well, yeah! -soft paper drivers would be affected in some minor way - you are adding a tiny amount of weight and for softer paper drivers you would change the stiffness when the paint dries - however for these drivers, we are dealing with a specific problem: they are from the factory covered in a (almost) ceramic compound called aquaplas, that is very stiff and rather heavy. this coating can crack and chips can fall off - if this happens you need to repair the chipping, but that’ll change the colour and will be visible - so the painting I did here is to finish such a repair. The JBL drivers were not assembled or coated that precisely from the factory, and the added paint in weight is not nearly enough to change the drivers specifications outside their normal range. ;)

@AlejandroGomez-yx1sg 3 жыл бұрын

Great Job, Soren. I was about asking the same question. I have a couple of JBL L100 century speakers and had always wondered if I should or could paint the white cones.

@SorenKoelbaek 3 жыл бұрын

@@AlejandroGomez-yx1sg You can! - of course I wouldn't if there aren't damages. The white cones will be yellowed over time, but it also bears some history and authenticity to it - it is hard to recreate normal aging. But if there is any kind of damage or tears - go for it! If you have any chips or breaks in the aquaplas I've had good experience with Texture paints, which are paints with small grains of sand in it, to mimic the rough texture. Of course testing on paper before the driver is a good idea ;)

@AlejandroGomez-yx1sg 3 жыл бұрын

@@SorenKoelbaek thanks a lot for your feedback! In fact, they are perfectly fine, justs normal aging yellowish. So, I will follow your suggestion 100%. Thanks bro.

@ScootieXP 3 ай бұрын

As someone who is contemplating buying a JBL set of speakers, which one would you choose? L100 or L112?

@SorenKoelbaek 2 ай бұрын

hard to say - the L-100 centuries have their shortcomings, the L112 some other. I really don't like the tweeter of the L112, and the woofer driver needs to be refoamed and therefore there is more maintenance. However, you might find they are not as "boomy" and "bassy" as I've found being the L-100 problem. end of the day, I would trry and listen to both and see whatever fits you. the good thing with vintage audio is you don't usually lose money buying and regretting :)

@ScootieXP 2 ай бұрын

@@SorenKoelbaek Thanks for getting back to me. However, please elaborate on the following: "However, you might find they are not as "boomy" and "bassy" as I've found being the L-100 problem." Maybe its my bad english but I didnt get that part. :) You lost me at the L-100 problem.

@SorenKoelbaek 2 ай бұрын

@@ScootieXP Your experience may vary, but in my opinion the L-100 tries to sound "bigger" than it is. Which results in a low-range that is not as precise at it should be: it has a lot of bass - for some modern music too much. Hope that helps.

@ScootieXP 2 ай бұрын

@@SorenKoelbaek thank you.

@earthexplorer579 Жыл бұрын

what size sand paper and paint you used here?

@SorenKoelbaek Жыл бұрын

I believe i worked from grit 120 to 320 and no higher. For the front face, just a matte black - I believe it's ral 9005 :)

@spanishjohn420 5 ай бұрын

where can i get new foam bits for the tweeters

@SorenKoelbaek 5 ай бұрын

They can be a bit hard to source - Ebay is your best friend, although I don't know any of the current sellers offering them, so I can't vouce for them directly. When you get them, please take care of removing the old foam and especially the leads for the driver than runs underneath. normally you can peel the old glue-pad off of the tweeter, but try to do it parallel to the leads so they don't break. There are a little bit of info and photos regarding that here: auditur.dk/jbl-l-100-speakers-a-guide/

@spanishjohn420 5 ай бұрын

@SorenKoelbaek Perfect mate thanks so much. I have ordered the foams from ebay and your advice is appreciated for when I fit them Thx

@cri1341 2 жыл бұрын

Buongiorno, quale suona meglio tra la 1 e la 2 e 3 serie. Grazie mille se mi rispondi.

@SorenKoelbaek 2 жыл бұрын

Hi Adriano, the 2nd and 3rd sound very similar and I haven't been able to tell them apart. The first is different; crossover and tweeter, but I do prefer the 2nd and 3rd the most. But your taste may vary :)

@RF1969 2 жыл бұрын

Por un momento pensé que le iba a echar café a la madera.

@SorenKoelbaek 2 жыл бұрын

That is an idea! - However linseed oil and terpentine performs a bit better ;)

@jeffm1896 11 ай бұрын

Doesn't painting the woofer change it's stiffnees and dynamics, increasing it's mass making it less efficient?i

@SorenKoelbaek 11 ай бұрын

In theory; adding mass to a woofer changes it's stiffness and mass - however there are a lot of changing factors in 50 year old speakers; the surround, the alnico magnetic field and the changing stiffness of the paper + aquaplas coating. On top of that, JBL (as with any manufacturer) produces units and crossovers and cabinets within tolerances, so adding a minute mass of paint to the woofer cone is not something you would be able to measure or hear in the final speaker. That being said, it is non-reversible so normally I would not do this, unless there was damage to the aquaplas coating or a previous botched repair (as in the video).

@fraula1 2 жыл бұрын

Hello. Did you really paint the woofer ??? 😳

@SorenKoelbaek 2 жыл бұрын

I sure did! - but only because they were damaged and had a repair ;)

@ic5720 2 жыл бұрын

La pintura al cono lo peor. Lo demás todo ok. El cono se debe limpiar de alguna manera no pintarlo, esa pintura en la bocina le quitó parte de sus hermosa apariencia.

@user-tv4tv2qh1w 9 ай бұрын

Человек хорошо делает не то что в наших роликах безвкусицв полная к

@rat8356 2 жыл бұрын

Um you forgot the most import thing!..The grills

@sadhooramrup4328 2 жыл бұрын

how much do they cost

@SorenKoelbaek 2 жыл бұрын

Not currently for sale

@wallylafferty1166 2 жыл бұрын

Whoa! What?! You painted the woofer's cone???!!!! Are you mad!? (Really, I'm just asking "Does that really work out okay?")

@SorenKoelbaek 2 жыл бұрын

;) - It does work. I wouldn't do it if the woofer was just sundamaged or could be repaired by other means, but applying a tiny amount of paint evenly to a woofer-cone is not something that in any way affects the parameters of the woofer outside of the specification from the factory - ie the tolerances from JBL are greater than what you can affect the woofer with. From an old JBL tech I've also heard using chalk mixed with linseed oil used on aquaplas coatings to fix discolouration, but I haven't tried it. But again: I wouldn't use it for discolouration alone. in this video it was done to hide a repair that was made to the aquaplas coating.

@VINTAGEs-ro1yv Жыл бұрын

What color is the spray 🙏🙏🙏

@SorenKoelbaek Жыл бұрын

It is Montana Gold eggshell primer :)

@SorenKoelbaek Жыл бұрын

I'll have a look and try to find the product no

@VINTAGEs-ro1yv Жыл бұрын

Thank you very much, I would appreciate if you write the paint code Thank you very much, I would appreciate if you write the paint code

@bigboykldaudiosounds3756 3 жыл бұрын

what spray did you use on those woofers ?

@SorenKoelbaek 3 жыл бұрын

I used an eggshell-white primer from Montana Gold - Only a very light layer is enough, and I would only do it to cover up repairs to tearing as was the issue here.

@icarosanchez5113 2 жыл бұрын

Tengo estos mismos parlantes para reformar incluso ya me llegaron los aros de espuma desde usa y también compre el enchape de nogal americano estoy mirando tutoriales como desmontar los woofer medios y twitter pero lo que si tengo claro es que el cono de woofer no lo tocare por nada del mundo porque esa pintura afectara su calidad de sonido

@alvaroriascos3004 Жыл бұрын

Tengo unos HPM 100 y quiero restaurar tanto sus gabinetes como los conos de sus Drivers ¿Qué sugieres para los conos de los woofers? Saludos desde Colombia.

@nopochoclos Жыл бұрын

1:.43 bad method, ,you need to apply glue to both parts first, then the part to be glued must be bigger, put over the entire side of the damage, then need to be sanded very slow, the part copy the damage hole perfect and like jigsaw no difference.

@SorenKoelbaek Жыл бұрын

Thanks for the feedback - I'll try that another time ;)

@dragonflymoxie5646 2 жыл бұрын

Ugh….painting a cone?….you may as well re-engineer the crossover to attempt fixing that fatal error.

@CaIIIKaTa 3 жыл бұрын

Never spray over speakers mate.. You lost me..

@SorenKoelbaek 3 жыл бұрын

Sorry to lose you - I'll try to give a little explanation then: The aquaplas coating on the 2123 drivers gets brittle over time and can crack if you have an accident. If this happens your only real solution is to replace the entire cone with a recone kit. The original recone kits are impossible to source however, and minor damages are therefore better to fix cosmetically and functionally instead. These particular speakers had been repaired in the cracked aquaplas coating leaving a colour-difference between the two drivers. You can absolutely paint over the repaired surface. You are not adding mass in an order big enough to change driver specs outside the tolerances when the drivers where manufactured or by the drift over time. The technique and material used varies from repairman to repairman, I've also heard of chalk being used by JBL service centers back in the 70's and 80's for re-whitening sundamaged items.