035TiA Disassembly
- Thread starter milo63
- Start date
Thanks I don't like Amazon so I did a search with their title. Found this The O Ring Store.
https://www.theoringstore.com/
Cord stock
https://www.theoringstore.com/index.php?main_page=index&cPath=117_119
Antique archaeology:
I've pulled six tweeters apart so far, some foam was stuck to the magnet, some foam was stuck to the inside of the dome, all foam was a crumbling mess.
My dissected pair of 035ti and 035tia. Both had what looked like it *might* have been the little guy perched atop the big foam piece. I'd guess it's purpose was to touch the center of the dome but it hasn't done that in years.
I might be doing this all wrong but the thought of that lump of rotting foam in my tweeters bothers me.
Old vs new
I've pulled six tweeters apart so far, some foam was stuck to the magnet, some foam was stuck to the inside of the dome, all foam was a crumbling mess.
My dissected pair of 035ti and 035tia. Both had what looked like it *might* have been the little guy perched atop the big foam piece. I'd guess it's purpose was to touch the center of the dome but it hasn't done that in years.
I might be doing this all wrong but the thought of that lump of rotting foam in my tweeters bothers me.
Old vs new
Sorry I missed this post. You are correct now to find a denser foam to do that job.
Getting there...
Zonker92
All shiny and chrome
OK. I’d started to think that maybe the little plug goes under the big one. But it sounds like you’re finding out for sure.
If you find a widely available source for the appropriate foam, it would be a great help if you would post that information here. A lot of people could use it. Thanks.
If you find a widely available source for the appropriate foam, it would be a great help if you would post that information here. A lot of people could use it. Thanks.
Last edited:
grey
Super Member
Finding the right material may be the larger hurdle. Density and shore hardness values must be of of some importance
. When I had oem samples on hand for the 044ti and 035ti, I didn't have the right durometer scales to measure these very soft materials. Did the next best thing and tested against other materials using my finger
. The closest match found was some saved product packing.
After inspecting a new pair of sealed 035ti, I went with that assembly order for my diy efforts.
center pole>large foam plug>small plug>ti dome
I've not found any of my pictures of the small plug yet. I do know that it is a higher density. The large plug is identical for the 044ti and 035ti.
. When I had oem samples on hand for the 044ti and 035ti, I didn't have the right durometer scales to measure these very soft materials. Did the next best thing and tested against other materials using my finger. The closest match found was some saved product packing.After inspecting a new pair of sealed 035ti, I went with that assembly order for my diy efforts.
center pole>large foam plug>small plug>ti dome
I've not found any of my pictures of the small plug yet. I do know that it is a higher density. The large plug is identical for the 044ti and 035ti.
![IMG_20180909_105327145[1].jpg](https://audiokarma.org/forums/data/attachments/1151/1151383-d8dbffe4cda67de5b2d6132bf0852437.jpg "IMG_20180909_105327145[1].jpg")
@grey Thanks for sharing, your experience and opinion is priceless.
https://www.ebay.com/itm/JBL-035Tia...5-L7-Others-/162923277235?hash=item25eefbebb3
It is my thinking that this kit is not meant for the 035, the magnet in the eBay ad looks different and poking at the remnants of my foam I can't see the top piece once being that little hard nubbin in the kit. I *think* it was just a smaller, thinner foam of the same material as the larger piece to fill up the dome. Adding a chamfer to a slightly thicker foam would accomplish the same purpose.
My aim here is to find a foam vendor that could cut a bulk order of the correct material in the shape we decide, be it one domed piece or two-piece.
Taking a break from this project to do some research and get input.
https://www.ebay.com/itm/JBL-035Tia...5-L7-Others-/162923277235?hash=item25eefbebb3
It is my thinking that this kit is not meant for the 035, the magnet in the eBay ad looks different and poking at the remnants of my foam I can't see the top piece once being that little hard nubbin in the kit. I *think* it was just a smaller, thinner foam of the same material as the larger piece to fill up the dome. Adding a chamfer to a slightly thicker foam would accomplish the same purpose.
My aim here is to find a foam vendor that could cut a bulk order of the correct material in the shape we decide, be it one domed piece or two-piece.
Taking a break from this project to do some research and get input.
One last pair...my garage 4406's*...what have we here?
The little nubbin under the foam on a magnet that looks EXACTLY like the one in the eBay ad.
There's more than one 035TI/TIA magnet/foam configuration.
*I've always thought that my garage 4406's sounded sweeter than my other speakers using the 035, is this the reason? :scratches head....
Edit: Just remembered that I recapped my garage speakers after a 120WPC amp, beer and the 4406's collided. I need to recap the fleet.
The little nubbin under the foam on a magnet that looks EXACTLY like the one in the eBay ad.
There's more than one 035TI/TIA magnet/foam configuration.
*I've always thought that my garage 4406's sounded sweeter than my other speakers using the 035, is this the reason? :scratches head....
Edit: Just remembered that I recapped my garage speakers after a 120WPC amp, beer and the 4406's collided. I need to recap the fleet.
Last edited:
The small piece is 6mm DIA., a fairly hard foam, doesn't seem like it's intended to compress. The larger 22mm DIA foam is extremely soft. The small hard piece sticks to the magnet first, then the softer one over it which creates a little more of a dome shape (which is pretty hard to create otherwise from a sheet of foam).If you put the small hard pellet on top, it would likely rattle against the dome as well as adding to the mass of the dome, ... two things you really don't want to do.
The attached photo is of NOS kits.
Thank you @SaturationPt
I could see that working for the domed magnets but I don't think the little nubbin will boost the large foam enough to do it's intended contact on the flat magnets.
Edit:
Gracious eBay seller reports that the old style used a smaller soft disk on top of the larger, replaced with the kit. Seller also said to leave screws loose and adjust fitment in the gap until there's a clean sine at 2-3Khz.....Now if I only had a scope...
Audio geniusing is HARD.
I'm loving this hobby, in the garage with music playing and my hands and mind occupied. (I come from a long line of tinkerers)
I could see that working for the domed magnets but I don't think the little nubbin will boost the large foam enough to do it's intended contact on the flat magnets.
Edit:
Gracious eBay seller reports that the old style used a smaller soft disk on top of the larger, replaced with the kit. Seller also said to leave screws loose and adjust fitment in the gap until there's a clean sine at 2-3Khz.....Now if I only had a scope...
Audio geniusing is HARD.
I'm loving this hobby, in the garage with music playing and my hands and mind occupied. (I come from a long line of tinkerers)
Whether it worked, it is the way that the kit is designed to be assembled. Happy to show you a kit if you're ever in this "neck of the woods" also. Many of the more modern JBL tweeter dampers have domed foam, but this was a cheap and quick way to create somewhat of a dome in a flat sheet product.
Sorry the photo doesn't show the smaller foam pellet well, it is die-cut in the strip, but the entire strip is packaged and not separated from the pellet until installation.
I doubt that you can find a foam too soft for this application. The foam was a very soft/light material, not designed to add any resistance to the motion of the tweeter, just prevent ringing by its contact/damping with the surface and to be springy enough to move up and down 24,000x per second when necessary.
I wouldn't worry too much about the hardness nor mass of the small pellet in this application as it never moves nor compresses. Could even use hard rubber I suppose if you find the right thickness, the original ones are pretty stiff.
grey
Super Member
This is my simple setup for testing drivers. If nothing else, it's good for a voice coil rub test. It's a Heathkit IG-18 for $30 + some reliability components replaced. Requires a suitable amplifier with an rms meter on the outputs to complete the test set.
Keep some free, full range speakers on hand to test everything before connecting the expensive units.
![IMG_20180911_145955569[1].jpg](https://audiokarma.org/forums/data/attachments/1153/1153184-f35f417572e856b99e0717dc51890b7d.jpg "IMG_20180911_145955569[1].jpg")
The 035 has assembly alignment tabs and you should be fine without this. Never hurts to check.
Last edited:
I believe that the assembly tabs are only on the 035Tia, not on the 035Ti.
gbCambridge
New Member
Hi, users in the UK might appreciate a UK link for appropriate foam. I found some very good material at https://www.ebay.co.uk/itm/193206988881 ....it is actually filter foam for fish tanks! It seems open enough and strong enough. More importantly, it has taken the edge off the harsh treble. and at £4.99 for a sheet 30 cm by 25, not exactly a budget breaker.
The foam is supplied in sheets 1.2 cm thick. I found that the old foam was completely hemispherical, which means it fully fitted into the titanium dome. I experimented with 1 cm and 1.2 cm foam and found no difference...so using the slightly thicker foam becomes much easier and tidier.
I kept the hard rubber piece which fits under the soft foam.
It is no more than a 20 minute job to change foam plugs, and most of that is cleaning off the old foam. With new foam, it would be much faster, which means it is easy to experiment with different matials and thicknesses.
The foam is supplied in sheets 1.2 cm thick. I found that the old foam was completely hemispherical, which means it fully fitted into the titanium dome. I experimented with 1 cm and 1.2 cm foam and found no difference...so using the slightly thicker foam becomes much easier and tidier.
I kept the hard rubber piece which fits under the soft foam.
It is no more than a 20 minute job to change foam plugs, and most of that is cleaning off the old foam. With new foam, it would be much faster, which means it is easy to experiment with different matials and thicknesses.
I haven't messed with it for a while but here's my process.
I bought the eBay kit and measured, a 7/8 hole punch is nearly perfect, 1/3" thick.
I used to work for a local major aircraft manufacturing corporation so I had access to lots of foam densities/types from shipping containers, the foam pictured was the closest to the kit I could find.
My band saw blade is a standard general purpose blade and it worked fine.
To be honest, even though the old foam was a gooey mess I couldn't tell any difference in sound.
Last edited:
