2245H recone or refoam?

[Ducatista47]

Opimax, maybe this would help, maybe not. Bo's post on the old and new 2245H cone designs.

http://audioheritage.org/vbulletin/s...5&postcount=61

Clark in Peoria

[opimax]

Thanks! appears to be the newer recone model on the ebay auction.

I have a velodyne sub (spl1200r), was going to get a 2nd one but will be buying this instead, hopefully replacing the desire to have the 2 smaller ones

Mark

[LowPhreak]

I'm glad this topic came up again, b/c one of my 128H-1's surrounds just disintegrated the other night. I was hoping it wouldn't happen at this time of year, but anyway...

With all of the stories about fairly shoddy recones done from JBL's Authorized Service and other places, I was wondering if any of you guys would like to take on a pair of 128' recones? R. Beardsley? Giskard?

Would it help if I said "please"?

[Robh3606]

Why don't you try to refoam them??? Take a look at this thread and look up Rick.

http://audioheritage.csdco.com/vbull...read.php?t=469

Rob

[opimax]

my first although only assisted refoam on 1 of my 128h-1. came with directions that did not need to cut the dust cap, centered using a 30hz tone. no problem even for a beginer, go for it, 25 bucks or so

mark

[LowPhreak]

Thx for the tips guys. Maybe I'll give it a shot. But who's got the re-foam kits?

How about these on eBay?: http://cgi.ebay.com/FOAM-SURROUND-RE...ayphotohosting

Are they just some generic surrounds, or do I need to get the Genuine Article from JBL?

[Robh3606]

Measure your cones edge to edge. Tell him the cone size and what woofers they are 128H-1 and you should be fine. His refoam kits are excellent. There are no genuine JBL refoam kits. JBL is recone only. These are black cone woofers??? If they are white they are 128H not -1. The cones can have slightly different diameters that's why you always measure them so they can be matched to the surrounds ID.

mailto:[email protected]

I just got a pair of 2108 surrounds from the same guy in your posted auction. They were a perfect fit. I didn't like how they were shipped in a soft bubble pack. I sent him an email and he said I was the first to suggest boxes and he never had a problem before. Looking at his feedback it's top notch.


Rob

[LowPhreak]

These are black cone woofers??? If they are white they are 128H not -1. The cones can have slightly different diameters that's why you always measure them so they can be matched to the surrounds ID.

They're 128H-1's, black. Standard issue for 4412's I assume. (?)



OK, well I'll check out the ones in the auction, and hopefully I won't make a mess of things.

[LowPhreak]

Measure your cones edge to edge. Tell him the cone size and what woofers they are 128H-1 and you should be fine. ...The cones can have slightly different diameters that's why you always measure them so they can be matched to the surrounds ID.

Another dumb Q, Rob: are you saying that all 128H-1 cones were not the same diameter and even knowing that these are -1's, I'll still have to measure them?

Now why would JBL go and do that?

[Robh3606]

Some of the 12" cones are not all the same size. Do they change in the same model number???? Not sure. When ever you go for a refoam kit you measure the cone. A 122A is larger than 128H-1 as an example. If l remember right the 128H white cone is also bigger OD wise. Look at the difference in the gap between the foam mounting pads.

Rob

[grumpy]

Just tell Rick what driver you have. If he has questions for you, he'll ask. I've done
quite a few (entirely successful) refoams including 128H with his kits which are well packed;
a recent 2214H set even survived the USPS postman's boot which crushed the center of
the box. -grumpy

[LowPhreak]

Here's the offending culprit sans surround. The cone measured approx. 9 3/8", so should be no prob there.

Using a screwdriver, I've scraped all of the foam & 99% of the glue from the basket edge, though it doesn't look so from this pic. I sanded the edge some to remove the glue, but didn't go radical down to the metal.

Is it neccesary to remove all traces of old glue?



...and here's the foam on the back side of the cone's edge. On the right I've already started, but getting that last little bit off of the actual cone surface might not be easy. I think I'll very lightly sand the residue off after the bulk of the foam is removed, to get a good surface to bond to, but not sanding into the Aquaplas. (I hope!)

Getting under those 4 wide spokes might be a bit tricky...



Meanwhile, I get to play the L channel in mono until the new surrounds arrive.

[LowPhreak]

Just got this e-mail, in case it may help others in the future:

Art,

JBl made the 128 speakers with two slightly different cones. There is no way to tell which cone you have without measuring. Most of them have the slightly larger cone.

Tom

We'll see which is the "slightly larger" cone.

[grumpy]

keep goin' dude. gaskets have to come off the frame too (carefully, if you expect to reuse
them). I've used a sharp x-acto knife, then fingers for rolling deteriorated foam off of the back
of the cone, then solvent. Different, wider/stiffer x-acto for the frame, then solvent.

Helps to keep the knife clean. I take off all the glue on the frame and any loose paint. Others
may have comments to complement the picture/story/example version here on the forum. I'd
certainly be happy to learn a new or better technique, but I've been happy with the turnout
thus far.

-grumpy

[LowPhreak]

FWIW, on the cone diameter:

Art,

That would be the smaller diameter cone. ...

Tom

Meaning this 9 3/8" unit is the smaller version. I don't know if that's good or of no consequence. (The smaller dia. requires perhaps a wider or taller surround, and hence a bit more Xmax?) He didn't say what the larger diameter's size is.

Here's the rear cone edge finished. Nice n' clean now. It was a tad fiddly getting under the spokes with a long screwdriver, especially the one over the tinsel leads, since the spokes are pretty low to the cone and wide, and nearly parallel to the basket's front plane.

I held the front edge of the cone with fingers directly under where I was working and scraping off the foam, so as not to bend or tear the cone. The screwdriver head was the same width as the flat mounting area, so it worked well.

Then I took some 80 Grit sandpaper and went around the flat area to remove the remnants of the foam. Just very lightly, and it didn't take much to clean it off.





Thanks grumpy, I didn't know the gasket had to come off too! I thought there was room enough to work around it. I'll get to it after dinner...