Sunday, March 25, 2012

Reconing a Kilomax

OK, this one's a little specific.  I realize this isn't going to get a lot of interest but I had to recone an Eminence Kilomax sub this week and it was kind of hard to find info about it on the net.  If you've never reconed a speaker you're missing out on a cool experience.  In the case of a larger cone you can easily save a hundred bucks by spending a couple hours at the bench.  There's a few things you need to know about like clearances and special glues but with so many specialty marketers on the web these days you can have a box shipped to your house with all the right stuff in it.

I didn't take any pictures because I wasn't planning on writing an article but I'll just go over the tricky bits for the next guy attempting this.

The first thing you run into on a Kilomax is that instead of a domed dust cover in the middle you've got this big embossed heat sink.  Flip the cone over and get the 4mm allen screw out of the center then flip it paper side up again.  Now here's the bit I had a hard time finding out.  Grab something sort of heavy and not too hard, leave the hammer and grab a chunk of 2 x 4.  Just whack the heat sink on the side four or five times until you see it start to budge.  Then you can just grab it and twist it out.

Then all the usual speaker change stuff happens where you cut the suspension and the spider, scrape off all the old glue and get ready to place the new cone.  There's one additional step on these because there's kind of a second spider mounted to a cardboard tube coming up through the center.  A good recone kit will have this part too so just break it out and scrape all the glue out of the hole.  Blast all the dust out of the gap with some air and you're ready to move on.

Putting it together is way easier if you get a kit that includes some shims.  There's nothing worse than spending all that time and effort to find that when your done and it's dry you've got the coil rubbing.  Set and shim the cone and glue it down, then add the gasket and glue that down too, flip it over and let the weight of the magnet hold it for a couple hours, then come back and glue in that central tube and second spider.  I was having trouble getting mine to stick so I grabbed the larger tube from the box, it's just shipping material, and weighted it down with just a handful of papers until the edges all stuck.

Putting it back together I took one extra step and got some thermal paste for the heat sink.  You can get it at Radio Shack and it's made for putting between computer chips and heat sinks to help the heat get out.  The sink only contacts the rest of the assembly at one point so a little extra help getting the heat out might mean a little less likelihood of another blowout. 

When I was all done I had a fully functioning sub for about $150 less than the cost of a new one.  My only issue was a little bit of crackle when I drove it hard.  I think I wasn't quite careful enough about the glue at one point along the edge of the cone and the suspension was moving a little too freely.  At the point I started to notice it I had the thing cranked though and unless the casual listener is going to have the grill off my cab and stick their head inside I'm not going to worry about it. Also I didn't carefully align the heat sink so the logo is slightly crooked but it's not where anyone can see it so I didn't bother to fix it.  If appearances matter in your installation check the alignment of the mounting holes in your cab and straighten it up.


You're the Scotty to our Kirk