Like most of you here I am a DIY person. I like to take on different projects ever so often to pass the time. I`ve built numerous car audio boxes, home audio/theater boxes, passive crossovers and now I`ve built a speaker. I didnt want to just recone one but rather get all the parts and build from scratch.
Before I got started, I read up on the process thoroughly. One important thing I came across was the centering of the voice coil. I`ve seen alot of subs in the classifieds where a guy threw one manufacturer`s kit onto another manufacturers motor and basket(eg jugg kit on an atomic motor). This is WRONG. You see the center of the voice coil has to be in line with the center of the magnetic gap of top plate. Above or below that, your BL symmetry will be way off and your TSp`s will be off.
while doing my research Ed Lester uploaded this most excellent video of the process which really helped me. I suggest you watch the entire thing.
The candidate is a blown RE SE 12.
These are the gutted soft parts: That coil is gone, not even a reading on the multimeter.
Next I separated the basket and motor. I taped up the gap so no debris fell into it and proceeded to clean the factory glue off the motor
By luck I came across a TC LMS coil on CACO which cost me less then the original coil would have. If you have never seen a LMS coil, this is what it looks like:
I encountered a minor issue with this coil. It fit, but the gap was really tight. No biggie, I sanded it down and got about 1mm extra clearance all round, which is enough. I then used a few sheets of paper to shim the coil for the remaining build process
Now if you watched the video, you saw how he calculated the coil over gap as well as the xmax. This coil is 60mm and the top plate is 14mm this means I must have exactly 25mm over the gap at rest and this gives me a whopping 39mm calculated one way xmax. It will definitely be less in reality though because of motor force differences etc. and these soft parts cannot support that range of movement but hey I`d have been happy with 20mm one way.
As luck would have it, my roll of blue painters tape is exactly 25mm wide so I used a piece to give me a better visual mark of exactly how deep my coil needed to be. You can sorta see it here:
I didnt mention before but the cone and spider I got were T3 soft parts meant for a 2.5 inch coil. Nothing an xacto knife and some careful measurements and cutting couldn`t fix. So heres the spider holding the coil snugly in place at the right depth:
Alot of "professional" repair guys use epoxy to repair speakers. Some epoxies dry hard with little to no flex, this may crack over time. What pro companies use is rubber toughened CA glue. I got a small kit of the CA glue that DD uses, at Triple R for $250; the glue and accelerator. I used half of the glue on this rebuild. So heres the primary joint with just the coil and spider:
and the entire" kit":
You need to be sure your measurements are even all the way around.
the basket was bolted back onto the motor and a bead of glue applied to the spider landing; not too much:
and as seen in the video piece by piece for the surround. I let it dry overnight:
The pigtails were ran and soldered into place. a little glue was used to secure the solder joint to the cone here. This is important, if you don`t you could damage the cone and or snap the tinsel leads from the movement of the sub.
The coil former was so tall I couldnt attach the dish dustcap in the normal fashion so I inverted it. Heres the finished product:
I tested it on my BASH home theater amp and it works perfectly. No rubbing and no noise. If you saw the post I made with the jig to measure your own Thiele Small parameters, well I will do that tomorrow. The FS will be very low because this coil feels almost twice as heavy as the original. Yes it will lower the sensitivity but I dont care. It`s going into my sister`s civic hatch and her front stage is a pair of DLS xprogram 5.25 comps. I wont be putting more than 300rms maybe 400rms on this sub.
Hope I inspired you to do something yourself.
Last edited by Soundstream_626 on March 6th, 2013, 5:55 pm, edited 1 time in total.
now that you say his motor had 2 1 inch slugs i found it strange how that top plate measured only 12mm. That top plate looked almost as thick as the slugs
