MCM 55-2421 came unglued in a T18. What alternatives??

[But it Hertz]

Here's a thread I started to get an opinion on the GTO804 vs 860W. Bill said the difference between the two are too small to make a difference.
http://billfitzmaurice.info/forum/viewt ... =1&t=18421

If the drivers weren't so difficult to install, I'd pull one of the Infinitys out of my Table Tuba and do a side by side REW measurement in my T18 using the Infinity and the Dayton. One thing I just thought of is that you might want to check the max mounting depth on the T18. The Infinity mounting depth is a little deeper at 5 3/16" compared to the recommended drivers.

That's great info, thanks.

Well I reckon the Infinity will fit in the hole OK, but I might have to rework the way the cover fits. I'll wing it when it gets here. HOPEFULLY the mounting holes will match up.

I just pushed the button with Amazon. My Infinity 860W will be here on Wednesday.

[Charles Warwick]

That's a spider glue line attachment failure and it is very uncommon to have one fail like this and it is indeed a manufacturing failure. MCM should have no problem doing a warranty exchange for this driver after they see the picture of the failure area.

Not that uncommon; MCM isn't the greatest in terms of quality control. The MCM in my TT had this exact problem. I used some super glue and fixed it. No problems with it for well over a year now. Just make sure you get the spider back to where it should be.
http://www.loctiteproducts.com/p/sg_ug_ ... ontrol.htm

[Tom Smit]

That's a spider glue line attachment failure and it is very uncommon to have one fail like this and it is indeed a manufacturing failure. MCM should have no problem doing a warranty exchange for this driver after they see the picture of the failure area.

Not that uncommon; MCM isn't the greatest in terms of quality control. The MCM in my TT had this exact problem. I used some super glue and fixed it. No problems with it for well over a year now. Just make sure you get the spider back to where it should be.
http://www.loctiteproducts.com/p/sg_ug_ ... ontrol.htm

+1

My son has an MCM in his TT, and when in the college dorm, he thinks someone may have run it too hard, and it too, separated. Once he brought it home, I used some two-part 5 minute epoxy, and let it rest for a couple of days. It's been able to pound now for the past year and a half.

Also, I have an MCM in my AT and it still works well.

[Gregory East]

Considering how many get used and abused they don't generate much negative commentary.

[Rick Lee]

Like others have said it's an easy fix- I used the two part epoxy on one that separated a year ago and it works great now.

[But it Hertz]

I did some research and found this fascinating video on reconing loudspeakers.

http://www.youtube.com/watch?v=lxGswEB3O_Q

If I have no joy with MCM I'll try gluing it as suggested. I agree, it looks like an easy fix.

[biggerrigger]

This seems to me to be a design failure in the glue up stage of building this particular model of driver. Seems to me that this problem could be easily fixed in the building of the cone assembly by adding a ring a glue to both the top and the bottom of the spider like used on most other drivers to prevent this from happening.

[But it Hertz]

Well it looks to me like the glue just didn't take to the spider. The ring of glue has texture from the spider... but it just didn't stick!

It's a mixture of cheap glue / shoddy craftsmanship / cheap construction.

The fact that people here are repairing their speakers with super glue or two part epoxy and then having them last for years... speaks volumes!

(Pun intended.)

[shawn_g]

...
The fact that people here are repairing their speakers with super glue or two part epoxy and then having them last for years... speaks volumes!

(Pun intended.)

Buh dum-dum-dum.

Good choice on the Infinity. I believe the rubber on the magnet assembly is removable if you need a bit more clearance.

Be sure to post a listening impression if you get a chance; I'm curious as to whether you'll notice any audible difference between the two drivers. Since the Infinity has a larger Vd, I'd expect it to have a higher max output.

[But it Hertz]

Buh dum-dum-dum.

Good choice on the Infinity. I believe the rubber on the magnet assembly is removable if you need a bit more clearance.

Be sure to post a listening impression if you get a chance; I'm curious as to whether you'll notice any audible difference between the two drivers. Since the Infinity has a larger Vd, I'd expect it to have a higher max output.

Yes, I will!

I can't wait to get it installed. I'm hoping I can get it in there without modifying the cover mounting.

I'll go ahead and break in the driver before I install it. That will be a looooong 12 hours to wait!!

So I called MCM. They were brilliant. Offered refund (even though I'm just over the 30 days) or exchange without argument. I have to pay shipping.

They will exchange it for 12 months provided you didn't cook it.

I'm going to hang onto it until the infinity arrives.. so I can more easily compare mounting holes.

[bassmonster]

Can you please measure the driver depth once you remove the rubber on the magnet assembly?

[Bryson]

My buddy has a dual TT and has been through a couple MCMs in that sub. Same issue. Just came apart at the glue. I'm pretty sure they warranty replaced both. Maybe a bad batch.

[But it Hertz]

Can you please measure the driver depth once you remove the rubber on the magnet assembly?

Sure. I'll take a couple of side by side pictures as well as how it fits in the T18.

Any other requests?

[Gregory East]

It looks like the rubber doesn't cover the back, only the circumference.

[shawn_g]

It looks like the rubber doesn't cover the back, only the circumference.

There are two little "nubs" that stick out. I'd guess you'd gain close to 1/4" of extra clearance without the rubber on there.

Here's an older (not very good) picture of mine to show what I'm talking about: