Opinions wanted: 240Ti vs L-150A [Archive]

BMWCCA

12-06-2020, 07:15 AM

I have to assume that across the Atlantic either of these must be rather rare.

Beyond the normal advice to purchase both and then make the determination for yourself, let me suggest that if the L150A costs double the 240ti then you'd either be over-paying for the L150A or stealing the 240ti.

I've owned my L112s since they were new. Nearly 40-years. I never thought of them as even superior to my 030 system I've owned for 20-years longer, but some of that is what you get used to. And my primary system is now 4345 so nothing else really stands a chance. I also own a pair of L150A, too, but really haven't used them much. And I have a pair of 250tis and a pair of L96s, so I'm experienced with most of the components of the two systems you are contemplating. I always loved the L96 and the L112 for the non-tiring nature of the phenolic tweeter. They really don't ever sound bad in any environment of on any type of material. The later titanium iterations of the 044 tweeter require superior program material quality to not occasionally become tiring to the ears. I'd have to say your enjoyment might depend on what you listen to, and whether the quality of the source is more important than simply listening to your favorite music complete with any flaws that exist in those recordings.

Obviously the L150A requires some space commitment, but to properly hear the 240ti you'll need to elevate them anyway, so that's not really an issue. They have a somewhat equal footprint. Then there's whether you like the deep base provided by the more modern 240ti woofer versus the nice balanced low-end of the older 128. And then also whether the bass coloring from a passive radiator hits you the same way as the more direct single cone. You likely won't dislike either but side-by-side your favorite may be determined by what you listen too, and where in the room you can place either. Remember the 240ti has a rear port which requires placement away from back walls and must be elevated to get the tweeter to ear-level and to keep the woofer from too much barrier reinforcement. The L150A is more self-contained and will pretty much play well wherever you place it.

Dagfinn

12-06-2020, 10:44 AM

Thanks for your responses, it helps a lot :). It clearly makes it much more attractive to give the lower cost 240s a shot. They do look good, space is there... :).

Located Norway, in the same area as Odd (you've maybe seen them on Finn.no, Odd). I'm not too familiar with the marked, but prices do seem high for some objects. I got back into vinyl a year ago, and revived my E100 Northridges from storage. After a year of rebuilding a vintage vinyl system and discovering a passion for vintage hifi, I thought these speakers now are ready to be replaced. I used to want an indestructable rock speaker, now I listen mostly to acoustic instruments in variety of styles. From '50s Art Blakey to Little Feat, Ry Cooder, Jennifer Warnes to Joni Mitchells early folk and later jazz period. But collection starts with AC/DC and ends with ZZ Top. Music is primary, sound number two. I will buy a better pressing, if needed! But I also found I enjoy the cultural heritage of hifi, so for me a Signet TK9Lca on a Kenwood KD550 with AT1100 tonearm, connected to Electrocompaniet EC-1 MM pre/phono stage amplified by a modern Abrahamsen v2.0 up integrated, is one signal path which makes me smile... :). To have something like the suggested sets to finish the line seems... right :).

So grand piano, standup bass, drums, some sax and some trumpets, many stringed instruments and multiple metallic percussives and lots of vocals are key words... Tom Waits, swordfishtrombones.

I heard the L300s some 45 years ago, and have never forgotten them. When I recently stumbled over the Troels Gravesen site, his writings actually tempted me to go vintage JBL, which he gives great respect to (for the same reasons I seem to remember).

Asking prices for 240s are $850, L-150As $1700. I'm sure there's some leeway on the 150's, didn't talk to the 240 seller yet...

Mr. Widget

12-06-2020, 11:23 AM

Considering the price differential, I would definitely go for the 240ti. Either speaker will be a significant step up from your current system, but the possible harshness of the titanium tweeter aside, the 240ti is a better speaker.

I used to have the KD500 table in a system with 4 SEAS 13” woofers... I had to build a special isolation platform to avoid feedback. Either of these new JBLs will have more low end than your current system, so keep that in mind.

Widget

grumpy

12-06-2020, 12:03 PM

My thought is that 70w/channel might not wake up the L150A.
I used a similarly powered integrated amp, that also doubled its power into 4 ohms, and was surprised at the difference when I replaced it with a 200w/ch separate amp. No ear-bleeding levels were involved.

I have not noticed this same effect with the 240Ti. Both are enjoyable. The L150A cabinets are more interesting looking, with the sculpted grilles.

SEAWOLF97

12-06-2020, 12:57 PM

I have 3/4's of the "Ti line" (18's,120's,250's) and like the teak styling and their build quality .

Cannot speak to the 150a's , never heard any, but did read some neg comments
on the 150 - NON a's. Cabinets seem good looking and well done.

The LE-14H-1 is a fine LF driver and very capable. I'm also partial to the 044Ti HF driver. It's not super crisp, but sound very nice to me. It's main drawback is that by now
the foam under the dome is most likely gone, rendering the HF a bit harsh to some people. Not too hard or expensive to fix.

For that price difference, seems like an easy choice , if all condition on both is the same.

Dagfinn

12-06-2020, 05:01 PM

Thanks again for your responses, and based on those I've simply decided to go for the 240Tis :D. Had a nice conversation with the seller, so all I need to do is arrange shipping, or go get them :D.

I've considered a potential need for more power, and do have a half idea of a 250w dual mono Electrocompaniet for an alternaternative line in the future. I already have the EC-3 MM. But the Abrahamsen may suffice, I don't play at extreme levels anymore. But, of course, maybe other reasons to have extra power...

As for drivers, I note the potential issue. Some foam dissolves in time, just have to accept and fix, if needed.

As for feedback, my floor is concrete and I use thick, non-resonant platforms, which seems to work very well together, no resonance enters via tt feet. My vinyl ...interest... has become several turntables, but they all sound the best on a firm, non resonant and heavy slab of something. Oh, and I used to have a B&W AS6(?) sub, to really shake things up, but I don't think it brought much to music with the E100s, so I got rid of it.

Anyway, I certainly would have liked to get both, but that is beyond my means in several ways. I need a bigger house, but that's not happening soon.

I hear some change caps and crossovers, is that something necessary to do? I can solder a little and have a electrical engineer as father in law who can help should need arise...

Bliss, I'll dream about big woofers tonight ;)...

BMWCCA

12-06-2020, 05:41 PM

I hear some change caps and crossovers, is that something necessary to do? I can solder a little and have a electrical engineer as father in law who can help should need arise...
Leave them alone until you've had a chance to really listen to them. There's likely nothing wrong with what JBL put in there decades ago.

Here in Amerika we have a saying: "If it ain't broke, don't fix it!" For some that should be "Fix it until it's broken."

grumpy

12-06-2020, 05:50 PM

I hear some change caps and crossovers, is that something necessary to do?

On a system that “new” I would expect not, unless something is damaged or you wish to alter the sound for some reason (rethinking or revising the crossover, for example).

There are those who choose to personalize their possessions as a necessity... a part of being involved in a hobby. Audio, cars, musical instruments, residences. Nothing wrong with that. Necessary? (Shrug)

macaroonie

12-07-2020, 10:10 AM

Incidentally , welcome to the forum , we have a few longtime members here from Norway and the rest of Skandinavia.

Electrocompaniet make some A++ amps , you should be on good ground there. Did you ever hear a Nordsk amp maker Auditon ? Very similar to Threshold / Pass.
Either of these would be excellent with the 240's IMO.

Other things you might want to ponder for the future , I reckon the 240 is a good mule , Bi Amping being an easy step.
However , and this has been discussed before , I think that removal of the mid and HF leaves cut outs that can be absorbed by the cutout for a PTH f1010 Horn. Add a 2450sl
compression driver and DSP management and you will be well on your way to a poor man's M2.
Endless fun during the long winter nights.

Just floating ideas here. :)

Dagfinn

12-09-2020, 12:17 PM

Thanks, macaroonie :). Adyton I do know by name and reputation, I've had the pleasure of talking to owner Geir Tømmervik at his shop. He's a well of information when he gets started talking :). Rare to see Adyton amps for sale, and what I have seen have been too rich for me. But nice deals pops up, you never know ;). Thanks for the tips, they are big boxes and space for mods - I see that.

I mentioned caps because seller mentioned some change them, but for starters they will be left as is, unless something is wrong. Seller says they're fine, no known issues :). They may need some surface treatment, but I think they look pretty good.

But, initally I'm looking for their original sound, and hope I don't have to change or fix anything :). I do have digital processing available as optional path in the setup, so - yeah, lots of fun for dark winter months :D.

They will be here come Friday, so I'll post some first impressions then. I'm going to need stands or bases for them, so that's one thing I'll have to fix :).

macaroonie

12-09-2020, 04:54 PM

Adyton --- yes , memory is faded. I only ever heard one and it was very very good.

On it's own the 240 is a damn good speaker , also quite a big boy , I have doubts about the stands but hey , ?? Whatever fits.

Where are you in Norway ?

Skol :cheers: Mac

BMWCCA

12-09-2020, 07:03 PM

My recollection was flawed about when we couldn't get the 240ti to perform as expected in the fabled Mid-Atlantic Speaker Shoot-Out years ago. We started with them on short stands and then setting them up on dining chairs. According to the just-after commentary, they actually produced improved bass when being compared to the L7, when we put them on the floor. Obviously boundary reinforcement is important depending on your listening environment; you may get too much, or you may need more. Placement seemed critical for the 240ti according to the golden-ears in this thread: http://www.audioheritage.org/vbulletin/showthread.php?22268-Dumb-thought-Anyone-ever-compared-an-L7-and-an-L300-side-by-side&p=226570&viewfull=1#post226570

That link was my posted summation of the day. There are many others throughout that thread that discuss the 240ti you may find interesting. Grab a beer and enjoy the whole thread!

Dagfinn

12-11-2020, 10:26 AM

Thanks, BMWCCA, will have a read :). I'm near Oslo, macaroonie. (Had a look at Adyton power amps; used from €4K and up. Some interesting pre/RIIA too, but not much info to be found.)

Picked up the 240s today, and have only played a few albums, yet enough to have a nice warm feeling inside and a big smile on my face :).

Authority, finesse, resolution, depth... power. Can't really play loud yet, but power/sensitivity seems no problem. What they deliver on lower volumes levels is just right, and some of what I've been missing, perhaps.

Well see about stands or platform, for the moment they sit on boxes bringing tweeters to ear height, some distance out from walls both rear and sides. Quite pleasing so far, I'll leave them there for a while. And the veneer looks even better than the pics in the ad, so I'm happy about that too :).

macaroonie

12-11-2020, 04:11 PM

Delicious. Enjoy and have fun with you favourite music. It's not a contest it's for enjoyment.

Dagfinn

12-16-2020, 03:14 AM

Thanks, macaroonie :). Don't think I could even enter any competition of that kind. Not that I need to anyway, it seems I have ample power resources - I can play much louder than wanted or needed.

So, after a few days of playing different music, I'm more than happy with my choice. Radka Toneff & Steve Dobrogosz Fairytales, one female voice and grand piano has never sounded so real, so rich in insight in the instrument and so close to the performer in my house.

For me they are a huge leap closer to stage or closer to the studio room, and music has gained both dimension and neuance. And more. It's easy to go on, but most of you know what a big, vintage woofer can do. On the other realism side, they are vintage so I'm trying to evaluate if the tweeters need a new damping foam plug. As far as I understand, the difference in a working or powderized/shrunk foam damper is subtle, so it may be hard to determine by ear. But to start with, I'd rather listen to positives than search for errors.

Tweeters out? (sellers pics)

macaroonie

12-16-2020, 03:38 AM

:applaud:

Henri

12-16-2020, 05:22 AM

Congrats! I'm entering the world of vintage JBL too!

Dagfinn

12-16-2020, 06:48 AM

Thanks, Henri, and good luck :)! It seems you'll be ready to party soon :applaud:. Look forward to hearing your impression of the 250's!

DavidF

12-16-2020, 06:40 PM

I sure do like those woofers. They are very tuneful and don't shy away from a little added gain once in a while.

clwinbe

12-17-2020, 08:06 AM

Dagfinn

12-27-2020, 05:43 PM

Hehe, clwinbe, I'm at loss for words :D.

After a couple of weeks I'm getting to know them a little better, and love is growing steadily. I've dropped them to the floor, no need to elevate them.

14 inches of woofer - yes! Also, I believe it playing up to 900hz, (or so), matters in coherence and dynamics. As a guitarplayer I'm used to being in rooms with drumkits and big bass amps, and in my youth I also worked as stagehand/PA/backline roadie. So I have quite a bit of experience with instruments and amps as they sound before recording. These speakers brings out those stage sound memories, which is both pleasing and surprising. As for organ, they will play church organ G0/24,5hz audibly, if not as forcefully as G1 at 49hz. :p.

As for tweeters, both are working without distortion, which is good. 044Tis are old, question is how age affects their sound.

But I find they play deeper in image, and with more layering than I'm used to. Spaces for new details have opened up, yet music/sound/instruments is/are more complete and distinct.

They are more revealing of bad productions/pressings, while others makes me think they were mixed on JBL studio monitors, and sound just perfect and better than ever.
But the system I'm building will allow for two signal paths, one fully analog, and one with DSP in line for EQ, recording and analysis/spectrum monitoring.

It'll take much more time to get to know them properly, but time I have lots of, and it'll be a joy.

Also I'm glad I found this community of aficionados and experts, feels much safer to have so many people loving the same thing - and who are sharing so willingly experience and knowledge... and passion, which is infectious, I have to say :D.

Thanks for leading me onto the path:applaud:.

macaroonie

12-27-2020, 06:12 PM

You should write reviews for magazines !!

So glad you have landed on your feet with your 240's and at a very fair price.

Seasonal greetings from Scotland , regards Mac

Mr. Widget

12-27-2020, 07:27 PM

14 inches of woofer - yes!

...Thanks for leading me onto the path:applaud:.Great to hear!

Widget

Dagfinn

12-30-2020, 03:49 PM

Incidentally , welcome to the forum , we have a few longtime members here from Norway and the rest of Skandinavia.

Other things you might want to ponder for the future , I reckon the 240 is a good mule , Bi Amping being an easy step.
However , and this has been discussed before , I think that removal of the mid and HF leaves cut outs that can be absorbed by the cutout for a PTH f1010 Horn. Add a 2450sl compression driver and DSP management and you will be well on your way to a poor man's M2.
Endless fun during the long winter nights.

Just floating ideas here. :)
Thanks mac, as you now know I like your idea :). Took a little time to read up on, but... very tempting.
87937
I did a little mockup based on the PTH1010HF-1 waveguide, very well fitting, would be invisible behind grill :). I tried overlaying the M2 waveguide, but it's just too big, I think. But would it be possible to use a passive crossover? My technical insight is limited, but something simple at crossing at maybe 800hz, would that work? JBL has some used in 2-way monitors. Or even build one? As a temporary solution, using existing DSP for EQ? Spread the cost a little... ;)

macaroonie

12-30-2020, 04:11 PM

I'm going to let the popcorn muchers get into this , lets see what they have to say.
Passive is entirely feasible with most of the network that is there , or the big components at least.

As it stands 900Hz , you could leave the bass part as is.

JeffW

12-30-2020, 04:18 PM

I think I'd build a new box rather than cut up a pair of 240ti to experiment on.

Robh3606

12-31-2020, 03:44 AM

Please don't take a nice pair of vintage speakers and butcher them. Leave them be and make new cabinets.

Rob:)

Dagfinn

12-31-2020, 04:12 AM

Hi Rob & Jeff! I do see your point, the question is how to make them sound the best. The 044Tis in mine are as old as any other 044Ti, and are in need of service to perform the best, they are in "original state", according to seller. I have some frequencies in their range which makes me go "hm", but can't tell why. Sourcing "as new" 044Tis seems difficult... New SB29BNCs?

As for building - I wish. But my workshop is limited, and don't have the tools needed to do a proper job. If I was building, I'd build M2s, I think ;).

But as the Stones are singing in the background "you can't always get what you want". I need good sound more than a museum, so maybe I have to choose (even if I want both). Waveguides would be invisible with grilles on ;).

SEAWOLF97

12-31-2020, 06:00 AM

The 044Tis in mine are as old as any other 044Ti, and are in need of service to perform the best, they are in "original state", according to seller. I have some frequencies in their range which makes me go "hm", but can't tell why. Sourcing "as new" 044Tis seems difficult... New SB29BNCs?.

044Ti Replacements are almost "unobtainable" ... It really is not that difficult to replace the foam in them before trying to find a suitable substitute.

a good thread on this procedure.

http://www.audioheritage.org/vbulletin/showthread.php?29325-044Ti-questions-Help-needed&highlight=044ti+help

macaroonie

01-01-2021, 04:17 PM

JBL have previous in this regard.

87956

DerekTheGreat

01-07-2021, 10:06 AM

I would vote for the 150a since the woofers are my favorite. I've designed systems with both woofers and think the 128h offered better performance, lower F3 and smaller cabinet. The 150 is unique as a passive radiator system hence the larger enclosure.

Just my opinion that's all.

My thought is that 70w/channel might not wake up the L150A.
I used a similarly powered integrated amp, that also doubled its power into 4 ohms, and was surprised at the difference when I replaced it with a 200w/ch separate amp. No ear-bleeding levels were involved.

I have not noticed this same effect with the 240Ti. Both are enjoyable. The L150A cabinets are more interesting looking, with the sculpted grilles.

...Picked up the 240s today, and have only played a few albums, yet enough to have a nice warm feeling inside and a big smile on my face :).

Authority, finesse, resolution, depth... power. Can't really play loud yet, but power/sensitivity seems no problem. What they deliver on lower volumes levels is just right, and some of what I've been missing, perhaps.

Well see about stands or platform, for the moment they sit on boxes bringing tweeters to ear height, some distance out from walls both rear and sides. Quite pleasing so far, I'll leave them there for a while. And the veneer looks even better than the pics in the ad, so I'm happy about that too :).

As an owner of a pair of L150A's, my vote was for the 150A's. Too bad I'm late to the party.. Not sure I'd want to spend $1,700 on a set unless they were mint but like Duane and grumpy said, the 128H is a damn fine woofer, but also, you need lots of power to properly drive a set. I've discovered by running twin Adcom GFA 555II's bridged (600wpc) is the ticket.

To express my favor of the L150A's, this past summer I went on a quest to try and replace them. Didn't really want to give up my Marantz gear so I tried more sensitive speakers, Klipsch. The L150A's battled Cornwall I's, Forte I and II's and then finally a set of JBL XPL200's. The L150A's lost their crown only to the XPL's. There is just something magical about the titanium tweeter, mid and running them vertically bi-amped. However, at the same time, I found that bridging those Adcoms to drive the JBL's was just F'in outstanding. They aren't as articulate in the upper registers or smooth or detailed in the mids but that's not trying to knock them, just nuances I noticed between the XPL's and the L150A's. However, that 128H in that cabinet with ~58g of mass on each PR300 (Factory is ~40g) the dig deep and are more accurate than the 2214H in the XPL200, especially above 100hz. This, at loud levels, more than makes up for the difference. So based on what you're listening to, a set of L150A's would treat you right and they do indeed look cool. An example of this extraordinary performance in the lows was provided by none other than the Beatles, "Honey Don't." It was so damn good I had to listen to it twice to fully appreciate Paul's bass plunkin'. Oh and of course, "Mercury Blues" by Steve Miller. I would have tried running the bridged Adcom's with the XPL's but minimum is 8 ohms and those are a 6 ohm system. Currently trying to figure out which older amps (because I can't afford new) will work with them. 200wpc from the Adcoms isn't enough...

EDIT: I really wanted to and still want to try out a set of Klipsch Chorus II's, JBL L100T3's and JBL 240ti's. Just before I got the Klipsch's there was guy locally (turns out he's also a member here) who was selling his but later parted them out. I passed because they didn't have the original poly 104H mids, maybe I shouldn't of. Another dude was selling a set of 100T's but the woofers didn't look right and he wanted too much. Although given I've tried the XPL's, I don't think I need to audition a set of L100T3's. SE Michigan is a dry spot for JBL gear as well as audio stuff in general. I had to drive down to Ohio just to get the XPL's and that guy met me halfway! Can't thank him enough. Think his name was Tom, maybe he's a member here. Only sold the set I bought because he had XPL 200A's. Said he couldn't notice a difference in sound between them but one set had to go so..

Dagfinn

01-18-2021, 03:22 PM

macaroonie

01-18-2021, 03:32 PM

Glad to help , good to see you back on your feet. Did Mats get in contact with you ?

Dagfinn

01-18-2021, 04:34 PM

Thanks mac, being sick with something which isn't covid is not top priority in healthcare these days :(. Didn't hear from Mats?

DerekTheGreat

01-19-2021, 12:14 PM

Thanks Derek & seawolf :). I've seen the repair thread, very nice (and somewhat scary). I'm considering buying a spare 044Ti to practice on or as backup, but so far no luck. The 150As are still for sale, now $1500, and wouldn't I like them too, but economy and space prohibits.

So I'm considering both a passive and active solution - thanks mac for all your help :)!

But it's not going to happen quickly. I may do the tweeter service route first, if I can find a spare for a decent sum. But waveguides are clearly tempting!

You're welcome! Thanks for reading my rant lol. Are you talking about my 128H's repair thread? OH boy, that was definitely a nightmare. I was close to setting the JBL's on fire or selling them. :banghead: Glad I didn't though! They're keepers. See if the one guy selling his L150A's will take $1,100? You miss every shot you don't take...

Dagfinn

01-19-2021, 04:36 PM

Actually Derek, I was thinking of seawolfs 044ti thread, but I'd like to see your 128H repair too? I have much to learn, for sure...

The 150As, I talked to him before buying the 240s, and he said he had rejected a lower offer than current price. But I'm quite certain I would have been happy with them too :).

Today I'm playing my 1976 Technics SL-150 with same age SME 3009 S2i tonearm with FD-200 damper. Cartridge is 1982 Signet TK7Ea, but with Audio Technica ATN150Mlx boron/ML stylus from mid 1990s. Phono stage is 1987 Electrocompaniet EC-1 MM/MC, powered by my 2015 Abrahamsen.

Listening to Paul Simons One Trick Pony, soundtrack but with many "live" tracks and Eric Gale plays a great guitar. One great thing about the 240s, I can play quietly, and still have a proper bass with tone, bassdrum kick and real dynamics in the instruments, with imaging and depth... :hyp:

DerekTheGreat

01-20-2021, 07:58 AM

If you haven't yet, try listening to Dire Straits "Brother in Arms" album. Great dynamics. I also like listening to Stevie Winwood's Higher Love. I would indeed like to see if the 14" woofer in the 240ti has any advantage over the 12" woofers in either my XPL200's or L150A's. The 240ti's are probably a better bet than the L150A's sonically. But as for appearance? Oh man, I love that white woofer, the aluminum edges of the drivers, veneer and flat black face the L150A's sport. I'm still somewhat searching for an affordable set of 240Ti's...

Dagfinn

01-20-2021, 12:19 PM

Unfortunatley I don't have vinyl versions of those album, may have to do something about that. I worked in a record shop when Brothers in arms was released, and got a serious overdose at work, never bought the album on vinyl :o:. Higher love is maybe the only album I can remember ever buying on cassette, for Christmas on the marked in Anjuna in Goa, India, 1986. A used walkman with assorted cassettes, and Steve Winwood was a clear winner. Back in the high life was a big hit on the porch in the jungle! Still a hit in my book :D!

DerekTheGreat

01-21-2021, 10:05 AM

CD will do, that's how I listen. I do have a turntable but I don't rock out when I play records. I have yet to do vinyl vs CD. Although the videos I have watched show that from a technical/engineering standpoint, they're the same. CD's actually get the edge, especially DVD's and Blu-Ray's being able to sample at 48/96khz.

Dagfinn

01-23-2021, 01:25 AM

It's one of those (whatstheword), I record digital only but prefer to listen to music from vinyl... :blink:. But really, quality of mastering for CD varies a lot, some is good, some not so good. Also, while the DACs are good, those first analog circuits after the DAC vary in quality. I'm ready to use DSP, so I'm not anti-digital. I'm anti lossy compression, though. (Some reference digital files here http://www.2l.no/hires/index.html? . Check out Arnesen: MAGNIFICAT 4. Et misericordia
Nidarosdomens jentekor & TrondheimSolistene).

Dagfinn

01-23-2021, 03:54 AM

Trimming M2 horns? This looks cheap? https://reconingspeakers.com/product/jbl-d2430k-tweeter-for-jbl-m2-5032754x/
88134

DerekTheGreat

01-23-2021, 07:33 AM

It's one of those (whatstheword), I record digital only but prefer to listen to music from vinyl... :blink:. But really, quality of mastering for CD varies a lot, some is good, some not so good...

I'd wager to say that comes down to the cartridge used on the turntable.. And those get crazy out of hand cost wise. I've got an Ortofon blue, and that's right at the cap of what I'm going to spend considering how little I use my TT. I feel fortunate though, that I bought my Denon DP 42F right before the hipsters made them cool again and thus increased the entry price.

CD quality does indeed vary, so too does vinyl pressing. My older friends would always say they exchanged lots of records two or three times due to bad pressings. Mixed bag for sure. What I like most about records is how intimate/involved the experience is. You really end up looking at the jackets, the record and most of all, engaging with the people around you. Hunting down second hand records is fun too. All of the digital music I mess with I do with lossless formats as well. Can't help the digital music I already have though. Although I can't always tell the difference, especially on modern MP3 recordings. When I do, I usually notice a higher noise floor and more fuzz in the upper registers.

Dagfinn

01-24-2021, 04:11 AM

I'd wager to say that comes down to the cartridge used on the turntable.. And those get crazy out of hand cost wise. I've got an Ortofon blue, and that's right at the cap of what I'm going to spend considering how little I use my TT. I feel fortunate though, that I bought my Denon DP 42F right before the hipsters made them cool again and thus increased the entry price.

CD quality does indeed vary, so too does vinyl pressing. My older friends would always say they exchanged lots of records two or three times due to bad pressings. Mixed bag for sure. What I like most about records is how intimate/involved the experience is. You really end up looking at the jackets, the record and most of all, engaging with the people around you. Hunting down second hand records is fun too. All of the digital music I mess with I do with lossless formats as well. Can't help the digital music I already have though. Although I can't always tell the difference, especially on modern MP3 recordings. When I do, I usually notice a higher noise floor and more fuzz in the upper registers.

I'm afraid I fell down the cartridge/tonearm/turntable rabbit hole some time ago, and secured a diverse stock of NOS styli and vintage cartridges. But I agree, a good nude, stylus is a must. Personally I use only linecontacts in some form, like ML or shibata. A Paratrace is also on it way from ESCO :).

But indeed, prices are rising and vinyl is getting more popular. I belive in 2019 vinyl beat CD in sales total (not units), according to RIAA.

Quality of vinyl is also a big problem, and more so now than it used to be :(. Seems some arts were lost during the last decades. Even Original Master audiophile pressings can be totally c***. Little Feat Dixie Chicken, for instance. Original pressing is much better. Same with (new) Tom Waits 180g remasters. Surface errors, piano distortion... (since my 197x copies does not show this distortion, I'm certain it's in the vinyl). Disappointing.

macaroonie

01-24-2021, 08:57 AM

M2 waveguide will be about 400mm once trimmed. Of course theat will mess with your grille mounting.
Note also there are some expensive bits and bobs needed to make it all fit together. Your neighbour Rob had some of those made. He is a serial trimmer so will be able to give you exact dimensions and a go -no go on the project.
It is this extra complication that inclined me towards the PT 1010 waveguide.

Cheers Mac

Odd

01-24-2021, 09:43 AM

Dagfinn

01-24-2021, 10:49 AM

Dagfinn

01-24-2021, 11:00 AM

If you want to build an M2 clone, it is better to have "trestokken (https://www.yourvismawebsite.com/trestokken-snekkerverksted-as/fresing-av-hogtalerplater)" make new boxes.

I have no connection to "trestokken"

Thanks, Odd! "Trestokken" looks both high quality and a safe way to go to make a clone... :). Nice to know about, from time to time I need parts made for projects requiring tools too expensive and large to own myself.

macaroonie

01-24-2021, 04:07 PM

Hmm, 400mm is within dimensions of the box - I could actually do it... :D

But I agree the PTH1010-1 looks much better, is easier and is probably cheaper to implement. Some mention crossing at 900hz as possibly too low for the PTH1010-1 waveguide? How high could the LE14H go? Would e.g. 1.2khz work? Also I've already forgotten why not use the D2430K driver from the M2 :o:...? Quite a few things to get my head around still...

As it is, they keep sounding better to me as I play them, so no urgency :).

Well , if you were to go down the path as iI suggested with the 1010 , the cutout for that waveguide would be within the cutout required for the M2 waveguide.. Cost of making that error of judgement ( if it was one ) $66 plus shipping per box.

PTH 1010 can be used with 2450 /2 / 3 with sl diaphragm and or D2 2430K as in M2

Dagfinn

01-25-2021, 04:34 PM

Well, if you were to go down the path as iI suggested with the 1010 , the cutout for that waveguide would be within the cutout required for the M2 waveguide.. Cost of making that error of judgement ( if it was one ) $66 plus shipping per box.

PTH 1010 can be used with 2450 /2 / 3 with sl diaphragm and or D2 2430K as in M2
:bouncy:

Appreciate your help, mac (even if you lead me into temptation :D). On paper several of the CD drivers looks usable and good, I'm trying to understand why some may be better than others... 2450SL vs the D2 2430K, for instance? I saw a test plot for pth-1010, (could have been first version), with 476Mg drivers which looked very impressive. As they did on M2 horns (Thanks Rob!). (I recognize several usernames I also see on diyaudio here, hi again everyone!).

As I'm educating myself, I happily found the FR plot for the LE14H woofer, so I know a little more what to expect from it as far as extension upwards, and what kind of flexibilty I have as far as crossing. LF extension is good for me :). Subs will never be on my list.

Edit: of course the woofer is LE14H-1, attachment irrelevant. At least I know where to search.

Dagfinn

01-25-2021, 04:56 PM

88155
LE14H-1, thanks Giskard. Looks good :o:.

Dagfinn

01-28-2021, 05:07 AM

Ok, this is becoming a different thread, I should make new thread under DIY for the continuation. Step one will be servicing tweeters one by one, so I know they deliver to their potential with no goo or fragments interfering. I have aquired a spare I will attempt first, as educational and backup, just in case. I don't want to be without music while I do the job either.

Should I proceed with rebuild, it will be by DSP and active solution. Also some non-destructive options have been suggested, but all are DSP based. I found a UMIK-1 locally, a useful tool I hope.

So procedure will be now be measure, restore 044Tis, remeasure & evaluate result :).

Thanks again for all feedback :)!

BMWCCA

01-28-2021, 06:20 AM

Dagfinn

02-14-2021, 07:16 AM

Did you already acquire the foam "plug" and, if so, what are you using and where did you source it?

Hi, sorry for the late answer, I've had a stay in hospital for some planned surgery, but recovering now.

I haven't got the plug yet, and don't know what to use. Perhaps look for a similar part, and work from there. I'd like to use something long lasting, but any more than that I don't know. I'm hoping to find some suggestions here to go by...

But, I've gotten a UMIK-1, so now I'll learn REW, little by little :).

Dagfinn

02-24-2021, 09:22 AM

Ok, after being lost in the Postal system, the 044Ti arrived today, and I just couldn't wait :bouncy:.

88302

It got a sqeeze during shipping, poor packaging :(

88303

But I managed, it came out looking nice :). Next is cleaning up, and then finding replacement pad. The old material is gong to dust when touched, so really good to get rid of.
Thanks to grumpy and seawolf for this http://www.audioheritage.org/vbulletin/showthread.php?29325-044Ti-questions-Help-needed&highlight=044Ti+repair

SEAWOLF97

02-24-2021, 09:34 AM

Ok, after being lost in the Postal system, the 044Ti arrived today, and I just couldn't wait :

It got a sqeeze during shipping, poor packaging :(

But I managed, it came out looking nice :). Next is cleaning up, and then finding replacement pad. The old material is gong to dust when touched, so really good to get rid of.
Thanks to grumpy and seawolf for this http://www.audioheritage.org/vbulletin/showthread.php?29325-044Ti-questions-Help-needed&highlight=044Ti+repair

looks nice ...
for foam, I just went through old packing boxes and found some pliable, but firm open cell foam that was older, but didn't seem to deteriorate at all.

the hardest part (for me) was getting all those blades inserted and hoping "the plinth" would not break or crack ... seems like you did fine. :) .... I like to mark 'the plinth" and the mag with a marker in the same spot when separating so to get correct (original) orientation when reassembling.

OH, and don't forget to blow out (with compressed air) the gap , sure some foam dust got in there ... can see in your pic.

macaroonie

02-24-2021, 10:23 AM

Good catch Dagfinn :)

Dagfinn

02-24-2021, 11:42 AM

looks nice ...
for foam, I just went through old packing boxes and found some pliable, but firm open cell foam that was older, but didn't seem to deteriorate at all.

the hardest part (for me) was getting all those blades inserted and hoping "the plinth" would not break or crack ... seems like you did fine. :) .... I like to mark 'the plinth" and the mag with a marker in the same spot when separating so to get correct (original) orientation when reassembling.

OH, and don't forget to blow out (with compressed air) the gap , sure some foam dust got in there ... can see in your pic.

Hi, and thanks again guys :)! Good idea, I must have some old foam somewhere. Matress foam, maybe?
Next one I'll use less/narrower leverage and more patience, even if it worked out without breaking. The double sided tape will let go, eventually. It is beginning to deteriorate too, btw (made 1987). The rear of the plinth may need some cleaning, the tape isn't sticky anymore. I'll post a pic of the rear too when I can take one. I did mark orientation just like you, and will do the dust job once I get my compressor out of storage :). But the tricky part is done, - couldn't have done it without the help I found here.

For reassembly I intend to follow described procedure: put som guides in the screwholes and lower into position using the guides. Since the tape isn't that sticky anymore, I wonder if I should replace it? The cleaning may be difficult/risky near the coil, and I wonder if extra tape may put it out of position?

SEAWOLF97

02-24-2021, 12:23 PM

Hi, and thanks again guys :)! Good idea, I must have some old foam somewhere. Matress foam, maybe?
Next one I'll use less/narrower leverage and more patience, even if it worked out without breaking. The double sided tape will let go, eventually. It is beginning to deteriorate too, btw (made 1987). The rear of the plinth may need some cleaning, the tape isn't sticky anymore. I'll post a pic of the rear too when I can take one. I did mark orientation just like you, and will do the dust job once I get my compressor out of storage :). But the tricky part is done, - couldn't have done it without the help I found here.

For reassembly I intend to follow described procedure: put som guides in the screwholes and lower into position using the guides. Since the tape isn't that sticky anymore, I wonder if I should replace it? The cleaning may be difficult/risky near the coil, and I wonder if extra tape may put it out of position?

>>Matress foam, maybe?
I would GUESS that kind of foam is CLOSED cell ??

I would not bother with the tape/glue ... it's the 4 bolts that hold & center it. The tape just makes it more difficult as once the dia is in place & stuck, cannot adjust.

IF you can't get to the compressor, maybe a wood toothpick could do it, but NOTHING METALIC into the gap. , but still blow it out afterwards

Dagfinn

02-24-2021, 02:32 PM

>>Matress foam, maybe?
I would GUESS that kind of foam is CLOSED cell ??

I would not bother with the tape/glue ... it's the 4 bolts that hold & center it. The tape just makes it more difficult as once the dia is in place & stuck, cannot adjust.

IF you can't get to the compressor, maybe a wood toothpick could do it, but NOTHING METALIC into the gap. , but still blow it out afterwards

Hm, I'm not too well informed on foams :o:. But, looking at https://www.foambymail.com/open-cell-foam.html, which would you choose?

It's not biking season, so I have to move some stuff to get to the compressor, but I will. I see minute fragments in there, and possibly space where dust could hide. The glue from the old foam plug is not so easy to remove after the plug has powderized, it seems. For other surfaces I would use a solvent to remove it, but since you mentioned non-metallic, maybe that is a bad idéa?

Also, out of curiosity and ignorance, what would happen if you used something metallic in there?

macaroonie

02-24-2021, 04:16 PM

You can buy comp air aerosols for cleaning electronic stuff.

Or CO2 canisters for beer , watch for frosting.

SEAWOLF97

02-24-2021, 04:39 PM

Hm, I'm not too well informed on foams :o:. But, looking at https://www.foambymail.com/open-cell-foam.html, which would you choose?

I'd go for the Speaker / Filter Foam (30 PPI) , but you only need about
1 cubic inch per speaker.

https://www.foambymail.com/SFF-/speaker-filter-foam-30-ppi.html

grumpy

02-24-2021, 06:57 PM

tape, sticky side out, on a stiff piece of plastic... e.g., part of an old credit card.
new tape, clean gap, inspect gap and tape, repeat until clean.

You don't want to add any abrasive or metal bits in there.

Dagfinn

02-25-2021, 05:23 AM

Great, I should get it clean :). I have a few foams available I've found, now that I know what "open cell" is.

88306
I very, very gently brushed off some powder sticking to the rear of the dome with a very soft art brush. A little is still left, but I don't dare pushing harder on the brush. Double sided tape is hardly sticky anymore, so I'll just remove what is loose and comes off easily...

grumpy

02-25-2021, 03:24 PM

That should be fine. The charcoal pick&pluck foam from the same vendor might be worth checking too (nice sized chunks pre-scored). Whatever is used should compress -very- easily. The foam plug that came with the factory diaphragm replacement was a bit taller than the height of the installed diaphragm at it's highest point on the dome, so there should be some foam plug compression when installed. There may be pictures in the 044 thread. I'd shoot for it just touching the top of the dome if unsure about the squish-ability of the foam.

Dagfinn

02-26-2021, 11:08 AM

Looking closer at foam specs, they have huge variance in "typical lifetime", from very short up to 18 years, as best I could find.

https://www.foambymail.com/hd36-hq-foam-sheet.html - typical lifetime 12 to 18 years. High density, support factor 1.9. Medium feel.
https://www.foambymail.com/charcoal-reg-foam-sheet.html - typical lifetime 8 to 10 years. Low density, support factor 1.9. Medium feel.
https://www.foambymail.com/speaker-filter-foam-sheet-30-ppi.html typical lifetime 5 to 10 years. No support factor data, but medium/firm feel.

:hmm:, makes me wonder how long the random stuff I have would last. Perhaps best to buy something with spec, would be sad to do it again in two-three years...

Alas, no shipping to Norway :(.

macaroonie

02-26-2021, 11:24 AM

One of the things that has always perplexed me about these foam plugs is that the idea is to control or reduce unwanted resonances.
To that end JBL set it up so that the foan would be touching the back of the dome under compression. I would assume that the amount of compression would have been established through testing. Maybe.
Lets take another look at it. The dome itself has rhat hydroformed pattern on the surface that is intended to break up ringing modes. In many tweets there is a felt damper behind the dome but not touching.
What we do know is that Ti diaphragms can have a tinsel kind of sound about them. This is the payoff for the light weight.
Now lets have a look at the dia in the 2450SL. 4" Ti with no ribs BUT it dous have a coating of magic dust ( fine grain Aquaplas ) This driver is known to sound excellent without harshness.
I wonder why JBL didn't just go this path and put a felt damper not touching the dome.
If it were me ,knowing what I know now having treated my own Ti Dias the transformation is very positive indeed.
I would be heading down this path if it were possible.
As you have spotted , there is foam and there is foam. All different never mind the thickness and hence compression.
Anyone have some magic dust out there ?

SEAWOLF97

02-26-2021, 11:41 AM

.

All 250 models were made in Northridge. All models had exactly the same enclosure dimensions and were built basically the same way. The woofer and mid bass were the same in all models. Only the 5" and tweeter changed. The best sounding model was the Jubilee and the weakest one was the original L250. From the 250Ti through to the Jubilee, this sonic difference was pretty small with each newer model sounding incrementally better. None of them had charge coupled networks, to my recollection.

it is true that there is a foam damping plug under the titanium dome. It does take a set after time and doesn't damp as well. Changing the plug usually brings the tweeter behavior back to original conditions. The biggest issue with the 250's is the failure of the woofer surround. If you can get the unit reconed or refoamed things go back to original. The LE 14-3 has a rubber surround which doesn't wear out. Although it uses a thicker frame, it will mount into the enclosure. The grille may or may not fit, however. The problem with this substitution is that the -1 woofer is about 1 dB lower in sensitivity. The LE 14H-4 is too loud by a dB.

The original L250 used first order crossovers with a lot of Zobel filters to true up the transducer impedance curves. Although a nice idea, the resulting sound was not as clear or detailed as all of the subsequent models. On those, I used a second order topology, but done differently than ever before. The sound was improved in clarity and detail. The 250Ti was the last of the series to use an in house built network. After that, we outsourced the networks from Taiwan since management closed down our network lines.

The Jubilee was the best sounding model by a little. It was just slightly smoother and a little more open than the previous model. We made 500 pairs which were ordered by and sold in Europe. I hope this helps a bit.

Odd

02-26-2021, 01:39 PM

Very interesting information, thanks for posting this.

.

Dagfinn

02-26-2021, 02:00 PM

Hm, I think if I could get the 12-18 year material, I'd start there and maybe try to measure my way to the right foam compression level. Long process perhaps, but maybe possible using a UMIK-1 and REW? Since the glue no longer sticks (at least on the spare), it is easier and less nervewrecking to disassemble...

Hi, Odd, sent my first order to Trestokken, nice guy - thanks for the tip! He's making some turntable parts for me already :).

Dagfinn

03-10-2021, 12:49 PM

So I'm considering using these for plugs, unused Thorens spring damper foam from recent replacement. Very soft and easy to compress, and I know they will not powderize over time. How long they will work is unknown, but after 40 years I know they will deform if heavily compressed. I have an old, used set with varying degree of deformation depending on compression, so I'm aiming for minimum compression. Not that I think they will last 40 years, but I have hopes for a few .

88409
88408
I think maybe trim them so compression is maybe 2 mm, or height is about 2 mm above the wood plinth? Judging pressure required is difficult, but in my mind they only have to touch lightly, compress only enough to maintain pressure and stop any "ringing"...

grumpy

03-10-2021, 02:17 PM

Sounds like a good plan. A few mm of 'squish' is probably safe, vs more for the original. But not being able to compare makes being conservative a likely wise move. Don't want to deform/damage the dome. You may also consider pre-shaping the portion that fits into the dome.

JeffW

03-10-2021, 03:53 PM

Here's a vid of Edgewound putting new foams in some 044Ti tweeters, for reference

https://www.facebook.com/UplandLoudspeaker/videos/660368414884259/

grumpy

03-10-2021, 09:36 PM

Nice. You can see how squishy the foam is. Lots of good info!

Congrats Grandpa Ken! :)

BMWCCA

03-10-2021, 10:35 PM

Here's a vid of Edgewound putting new foams in some 044Ti tweeters, for reference

https://www.facebook.com/UplandLoudspeaker/videos/660368414884259/Did I miss a step? Did Edgewound glue the "plinth" back to the base after running the sweep? If so, what type of glue was used? Thanks for that.

Dagfinn

03-11-2021, 02:03 AM

Very informative video, thanks a lot :)! I think the foam I have found is very similar to what he's using, very soft. I will trim them a little, and maybe "dome"-shape them as well. He's compressing more than I imagined, so I'll make them taller than I first planned. I was afraid of over-dampening, but seeing what he does I'm confident I'll be fine :).

He doesn't say whether he glued or not, he just skipped from "be very careful" to "ok, the diaphragm is reattached to the magnet". He does mention "checking alignment" when mounting the cover, so I'm not sure it's fixed in place? Guess I'd be partial to using some dots of the same double sided tape as originally used, to maintain position while reattaching the cover and still be able to disassemble it again in the future...

Great video find! :applaud:

JeffW

03-11-2021, 08:08 AM

I don't know if he re-glued or just used the bolts to hold it - I've seen posts where the glue was omitted.

He has quite a few vids on his Facebook. I don't have Facebook, but there's a link on his homepage

http://www.repairspeakers.com/

LHorn

03-11-2021, 12:27 PM

Sorry to butt in here..but I have 8 of the 044Ti's to refoam as well. My question is this...is the foams purpose to mechanically dampen the dome from resonating or is it to block sound waves from bouncing around under the dome hitting the pole piece? If the latter I could see using foam..but if it's to dampen the actual dome why not coat or put a drop of something rubberized on the inside of the dome?

I did see a while back where someone coated the outside of the dome with Aquaplas...but I wouldnt want to do that..even if I could get Aquaplas.

JeffW

03-11-2021, 12:31 PM

LHorn

03-11-2021, 12:46 PM

Right...I guess it makes sense..if the ringing would be caused by waves bouncing around under it the foam wouldn't necessarily need to be touching the dome...just like the insulation in a cabinet doesn't have to touch the drivers for instance.

Thanks Jeff.

macaroonie

03-11-2021, 04:14 PM

In the vid above, Ken mentions that the foam is to contact the rear of the dome to damp the ringing of the titanium dome.

As to why JBL decided on that as opposed to putting a drop of something on the back of the dome, I couldn't say.

Aquaplas seems to work pretty well on the 2450SL diaphragm.

Might be worth a go if you can get your hands on a little.

My own digging on this subject suggests that the coating on the 2450SL is much finer in texture than that used on bass drivers.
Mortar and pestle ??

Edgewound does Aquaplas treatment on bass drivers ( I believe).

grumpy

03-11-2021, 04:59 PM

JBL did put aquaplas on these Ti domes... LSR32 and 28. 053Ti ... don't know if that was instead of, or in addition to foam. :dont-know:

Also, the residual adhesive on the 'plinth' is sufficient to keeo things from moving around once the screws are in.

macaroonie

03-11-2021, 05:46 PM

Grumpy was that on the outside ?

I got a small amount via a connected member and applied it as he did in a thread here.
It definately took away that tinsel sound that Ti has. It seems quite gritty , is water soluble and paints on quite easiy , when it dries it is well stuck to the dia , not flakey.
Actually for a non factory application it was easy to get a satisfactory visual result.
Just enough to get an even non patchy coating.

88413

Outside it is. No ribs on that diaphragm I notice. My conclusion is that the ( Antivibe ) is a sufficiently efficatious treatment that they were able to do away with the rib forming process.

JeffW

03-11-2021, 05:47 PM

Aquaplas seems to work pretty well on the 2450SL diaphragm.

Might be worth a go if you can get your hands on a little.

My own digging on this subject suggests that the coating on the 2450SL is much finer in texture than that used on bass drivers.
Mortar and pestle ??

Edgewound does Aquaplas treatment on bass drivers ( I believe).

If they weren't so hard to come by, it might be worth a shot. I'll not be trying it on mine :D

grumpy

03-11-2021, 09:34 PM

Yes, same lack of ribs on the aquaplassed 4" dias. I bet they tried it. Probably dampened the upper freq tizz that the stiffened/ribbed diaphragms added to measurable and noticable effect, so why bother if it took that away. (conjecture)

The factory black coating looks sprayed on and the 'grit' is quite fine, unlike the stuff folks were hand painting their 2435Be drivers with awhile back (most seemed happy with the result, regardless). Front vs back? Probably much easier to evenly spray a diaphragm on the convex side, and easier to identify and differentiate in the marketplace... less distracting in the studio on an all black monitor. (more conjecture)

I have a LSR28 with a wrinkled dome and a spare 053Ti available to replace it (not in any hurry as the wrinkled one ended up sounding fine)... but if I ever swap the new one in, I can check to see if there's any foam behind the dome. I am a bit curious now, but don't hold your breath. Maybe someone else has taken one apart. I don't think they ever sold repair kits, just entire tweeter assemblies.

LHorn

03-12-2021, 10:30 AM

I was looking at the 1986 Ti brochure and found this interesting. JBL states that the diamond pattern in the surround and the ribs in the dome raises and lowers the resonant frequencies to above and below human hearing...along with strengthening the material. Nothing mentioned about the foam.

In the one paragraph they state that other manufacturers use "high internal dampening" to control resonances...but I dont know what that means. Is the foam considered internal dampening? Is the foam an afterthought due to the patterns not quite doing what was on paper?

88418

Dagfinn

03-13-2021, 09:02 AM

*Sigh*. If you look closely at the pics of the tweeter, there's a small black dot in the middle of the dent in the first picture. My friend in France recieved it like that, yet in the pics posted by the seller it was undented. The black dot is a tiny needle hole :(. It looks punctured on purpose. I didn't catch it until today, my eyesight is less than perfect.

Anyway, looking at the foam plug again, there's a lot of pressure needed to compress that plug from 1/2" to the height of the dome+thickness of plinth. I wish he hadn't skipped that part in the video. For me, the weight of the plinth/diaphragm isn't enough to hold it in place, by far. The stickyness is gone from the old tape; I'm wondering if it was there just to be able to assemble it, due to the pressure from the plug? The tolerance for misplacement is tiny, and any foam plug I can imagine will push it out of position without adherence.

But, what will the hole do, you think? :crying:

SEAWOLF97

03-13-2021, 10:31 AM

grumpy

03-13-2021, 11:38 AM

Personally, i’d leave the hole alone and not worry about it.
re alignment, if the adhesive is now completely ineffective, you could try thin, double sided tape... A sweep test will bring out any buzzes. I’d just visually center it and test. It sounds like you’re experiencing more back pressure from the foam than I would expect (not having the factory foam is why I suggested trimming it a bit more; the compression doesn’t need to be more than a mm or two as the dome excursion is very small).

Dagfinn

03-13-2021, 12:46 PM

Ok, I see. As you say, it's already there so... Guess I'll ignore it for now and proceed. I should be able to generate a sweep test, hopefully that will tell me something. It's a backup, but I still hope it's working ok. I've found that vintage gear often needs some investment in time or parts, or both. And some self education, so thanks for your guidance and input :).

This guy is fixing a 2412h driver, https://youtu.be/YNaTzoI-i7M
The 2412h uses a foam plug see 2:42-3:12. I wonder what they do to replace them? 2412h seems like a more current product?
And, they have "direct copy of 035Tia" which has "Foam plug behind dome to reduce unwanted ringing and resonance" https://www.simplyspeakers.com/replacement-speaker-jbl-tweeter-t-035tia.html

I sent them a request, maybe it could be possible to get plugs from them...

grumpy

03-13-2021, 02:47 PM

There was someone selling an equivalent item (as stated by the seller) on ebay at one time (?) or perhaps contact member Edgewound for one of his.

Ok, I see. As you say, it's already there so... Guess I'll ignore it for now and proceed. I should be able to generate a sweep test, hopefully that will tell me something. It's a backup, but I still hope it's working ok. I've found that vintage gear often needs some investment in time or parts, or both. And some self education, so thanks for your guidance and input :).

This guy is fixing a 2412h driver, https://youtu.be/YNaTzoI-i7M
The 2412h uses a foam plug see 2:42-3:12. I wonder what they do to replace them? 2412h seems like a more current product?
And, they have "direct copy of 035Tia" which has "Foam plug behind dome to reduce unwanted ringing and resonance" https://www.simplyspeakers.com/replacement-speaker-jbl-tweeter-t-035tia.html

I sent them a request, maybe it could be possible to get plugs from them...

SaturationPt

03-14-2021, 10:48 AM

I'm a little fuzzy on what you're looking to repair.

The 035Ti was first produced without a piercing. The 035Ti was then revised, with a piercing in the dome like your photo, but the P/N was unchanged. My 4312As first came with the un-pierced domes, later while still in Germany they were changed to the later pierced-dome 035Tis, an upgrade. I can't recall what it was that JBL found that was solved by the small piercing.

All of my D8R035Tia kits have the piercing. I haven't looked closely at the 044, but it wouldn't surprise me to find that at least one revision of it also has the piercing. I have no spare D8R044 kits so the only ones I have I'd have to peer through the screen, and with my aging eyes that's a challenge in itself. I tried a few minutes ago to look through the screens but can't tell.

The only way I can see currently to get a good matched pair of 044s is by buying a pair of used 1.8Tis, throwing away the cabinets (and probably the woofers), they often sell for less than the value of the tweeters. I would prefer to buy a pair, especially used or aftermarket, as matching tweeters (and mids) are extremely important to your imaging. When I bought my 240Tis (used) I couldn't find a pair of new JBL diaphragm kits to hoard, so I bought a nice pair of 1.8Ti speakers instead, ... as spare tweeters (kept the 1.8s, they are nice office speakers).

Regarding the damping foam (not "dampening"): The original and the 035Tia series kits include one open-cell foam pellet, which goes on top. Adhesive-backed / self-stick. It also includes a small, harder black pellet of a high-density foam rubber, self-stick, which is to be stuck down to the pole-piece first. The larger/softer piece then sticks over it and forms a dome shape to match the inside of the Titanium dome. I did measure the two pellets in a kit once, posted on AK some years ago, not sure if I still have those dimensions. The larger foam was the same density material that is used by Simply Speakers as the diffraction ring for the L100A speakers and is what I've used. The small pellet can be cut from rubber, I used gasket material. That small pellet was not designed to compress, just a "dead" piece of material that forms the dome in the larger pellet.

Incidentally, when I opened my last 035Tia kit a year or two ago, the larger foam pellet had started to disintegrate, was becoming unstable and had turned from resilient foam to fragile, and was only useful for dimensions and I had to make new damping foam for it. Being that mine were fairly late production and stored inside in air-conditioning and out of sunlight, I am confident that you won't find any around with good foam.

Ed Kreamer

03-14-2021, 02:00 PM

Colleagues,
Ken does use a "spot" of glue on the pole piece to hold the foam in place.
Edge wound does great work, he did some 2214's for me a few years ago. I;m going to attempt doing a plugendectomy (which looks like it's 3/4 inch dia. and 1/2 inch thick) on my 035's I have 4 of them that need help.

So thanks Wolf for the foam link.

Oh yes a note of caution to those who haven't worked on 035's before; Ive ruined 2 of them by not taking adequate caution. So be careful and take your time.

Ed

SaturationPt

03-14-2021, 05:08 PM

This is the complete D8R035TIA kit, note the small pellet (die-cut but not pressed out of the square piece yet) next to the larger low-density open-cell pellet.

macaroonie

03-14-2021, 05:41 PM

Having worked in manufacturing this looks like a bodge to me. It's not uncommon in the world of hi fi , a couple of reviews flag up an issue and you do have to go back and make a fix , if you can.
You can see it all over turntables if you have a keen eye and look under the hood.

I have a pair of 044Ti that have not been opened from new , in all likelyhood the foam will be mush. I'm motivated to get my hands on some magic dust plus add a felt domed backer on the pole piece ( not in contact with the dome )
This FWIW is straight from the compression driver world where the foam in the back cup is replaced with felt and some dia's of course have the magic dust.

I'll report back when I get round to it.

Here's a bodge if thre ever was one. This is the sub chassis from an Ariston RD11 circa 77/78.
The original chassis was the shape of the pressed part below the obviously added on part got added and spot welded on. This was not the original design.
Total bodge to effect a change that circumstances deemed necessary.
Happens all the time.

88427

SEAWOLF97

03-14-2021, 06:07 PM

.
On the first 044Ti , I did the 8 screwdriver blades under the "plinth" to
remove operation and waited an hour for it to "pop".

On the second one I did, got a little smarter. Took about 2 minutes.

took the pocketknife ... laid it against THE TOP at a 90 degree angle.
Then pulled the blade back so that the tip was about a half inch from the dome.

took some tape and attached to the blade at the edge of the plinth as a depth marker guide.

put the blade tween the plinth & magnet up to the blade tape marker and just ran the blade around 360 ... came right off safely. :D

Dagfinn

03-16-2021, 03:56 AM

I'm a little fuzzy on what you're looking to repair.

The 035Ti was first produced without a piercing.
I'm trying to fix some 044Ti's with powderized damping plugs. The 044Ti wasn't pierced originally, so I'd be hesitant to pierce it, myself. I was hoping a 035Tia foam plug could maybe be compatible, but the shop didn't sell foam plugs separate. I think everyone is punching their own. I have ordered some more foam, actually maybe the same diffraction ring you mention :)!

Ken mentions using acetone to loosen the glue, but I'll certainly go slow and easy on the next tweeter. Knife tip method may be worth trying too, thanks for that tip Seawolf.

Mac, I'm eagerly awaiting your magic dust results :)! If there was a box of JBL-aquaplas available, I'd go for it, for sure. The foam plug is bound to degrade over time, not a perfect solution from the start, and maybe even creating its own problems when degrading and maybe filling the gap for the diaprahagm. The Thorens foam I have was an afterthought, to cancel resonances from footsteps in the spring suspension ;).

Curiously, another set of 240Tis have shown up locally, twice the price of mine, yet strangely attractive... :blink:.

Dagfinn

03-16-2021, 04:06 AM

Here's a bodge if thre ever was one. This is the sub chassis from an Ariston RD11 circa 77/78.
The original chassis was the shape of the pressed part below the obviously added on part got added and spot welded on. This was not the original design.
Total bodge to effect a change that circumstances deemed necessary.
Happens all the time.

88427

Interesting to see this sub chassis, I have a Heybrook TT2 which is very much the same design principle, yet solved slightly differently.
88433
88434
New temporary armboard, different arm coming in a while.

SaturationPt

03-16-2021, 07:15 AM

Absolutely no reason to pierce a diaphragm that isn't pierced Dagfinn.

As mentioned, I don't know that the 044 is pierced by JBL, I am more thinking that someone installed an 035Tia dome somehow. The 044 is a slightly different tweeter and might have a different venting scheme.

As far as adding mass to the dome with aquaplas or other, I'd consider that experimental on the 044, if it works that is great, but I would leave it to those among us who can actually measure the results and that isn't me. It might change the response of the 044 tweeter in ways other than just damping a resonance.

It has always been interesting to me that JBL discontinued the embossing on the dome when they designed the 052, how I'd like to be able to understand what changed and why. Of course the next version the 053 had no embossing either, and included the coated dome, but again it was a complete redesign, not just added coating.

Also as someone mentioned below, JBL does only offer a complete tweeter, there is no 053 repair kit at this point, and it is designed to be used with a waveguide (I am not aware of any application with the 053Ti that has a flat face).