How can i ......


get a woofer out of the cabinet ?

I have a good sized subwoofer with a 15" driver that i'd like to do some internal mods / repairs to. In order to do this, i have to take the woofer out as it is the only reasonable sized access point to the internals. The problem is, i can't get the rassafrassin' driver out of the box. I have tried everything that i know to do this without going "bonsai" on it. I almost think that the driver was not only screwed in but also glued in place.

The woofer is a JBL 2235, so it is a sturdily built driver. All of the screws have been removed that hold the driver in place and the rear hatch for the binding posts have been removed. Having done that, i can push directly on the rear of the driver and NO luck what so ever. I have even tried pushing on the driver from the rear while my brother tried to pry the driver out from the front using a large screwdriver as a wedge. The only result of that effort was a small amount of damage to the baffle from the screwdriver digging into the wood. Luckily, that is all hidden under grille cloth.

Short of resting a 2 x 4 on the back of the driver and whacking it with a hammer a few times, has anybody got any suggestions ? This one has been a real ....... to say the least and i want to get it out of the house. It is a gift for my Dad, so it can take up space over there once i can figure this out and get it done. ANY help or suggestions appreciated ( short of a stick of dynamite ) : ) Sean
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sean
Sean,

It may be either some type of caulk or gasket that is stuck. Maybe the speaker was inserted when the finish was fresh. I would try a flexible knife such as a filet knife. With the blade laying flat to the cabinet use a sawing/rocking motion all around until you've freed the mounting flange. You may even be able to put masking tape on the cabinet to prevent visible damage.

Good luck.
Oh yeah, if this works, I predict blisters on your fingers. I figured it appropriate to quote John Lennon.
The heat's a good idea too. If you don't have a heat gun then a hair dryer just might do the trick, although slowly.
Thanks for the ideas guys but i forgot to mention one very important detail. That is, the woofer is flush mounted i.e. countersunk so that the outer edge of the woofer is flush with the baffle. As such, you can't really get behind the edge of the basket with anything, hence the small "chunking" of the cabinet when we were trying to pry the driver out. As such, the filet knife ( very sharp and thin blade, which was great thinking ) would probably just snap off due to the severe angle that would be required.

As far as the heat gun goes, i don't think that i can get one in from behind the driver as there just isn't any room to get into the box any other way. That's why i have to remove the driver to begin with i.e. to get access to the internals. There is no way to heat things up from the front without doing massive damage to the surround of the driver. That was a good suggestion though.

How about "round 2" now ? : ) Sean
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Huh...

Make sure their are no internal mounts holding the driver in place. Feel around the perimeter on the inside the driver and make sure their are no "clamps". Being a 15" I would think you could get some leverage from the rear to break loose and glue/varnish.

Rocking/twisting motion on the magnet assembly to loosen things up. Hopefully not the magnet assembly itself.

Leave it alone for a day and come back with a clear head. Try not to think about it during the day.

Swift kick.

Good luck,
Marty
The lids on paint cans are flush mounted. How about trying a few of the hooked tools specially made to open those? At any rate they're cheap :^)

Btw, I've pried out large sealed woofers from Advent and Dynaco speakers. Some of the MDF may indeed rip loose while lifting the woofer frames. Another use for Blu-Tac?
If you only need to gain access to the innards of the cabinet, why not saw a large access hole in the back of the cabinet and then reseal it after you're done modifying the unit? I know this is kind of a "last resort" approach, but if nothing erlse works ...
Maybe a homemade gear puller type of approach, threaded rod that will push it slowly out from the rear as you turn the rod. You can make a wood support frame that clamps the box from the front and rear with only the rod pushing from the rear as you turn the screw against the rear. Hope you understand what I'm getting at?
I think Marty may be right. It may be attached from the back side. See if you can see anything with a flashlight from the back or what. You will be working a long time prying it out if the woofer is screwed in. Many modern things aren't designed to come apart (easily) once they are put together. Arthur
Sean, you're gonna go "bonsai" on that thar rassafrassin' driver? You mean you're gonna sculpt Japanese trees on it? Hah!

If you decide to go "banzai" on it, I'd definitely see if there's a way to get around the back to verify nothing is keepin' that bugger in there other than glue or caulk.

If you don't find clips or internal screws on the back side I think prying it may be the only way, and unfortunately the scariest because you wouldn't want to bend the woofer assembly or damage the cabinet.

Good luck!
Round 2: [Act of desperation]
Find a narrow hall way or a door jam and place a wood support against the wall and behind the magnet structure of the driver. Position a 2X4 behind the wood support protecting the magnet cover of the driver; making sure the 2X4 is long enough to extend beyond the cabinet. Position a scissor jack etc. between the wood support for the wall and the 2X4, then extend.
Perhaps a solvent? The first one to come to mind is nail polish remover, but a good cabinet maker would know better than I would. How about applying just a little overnight and see if that loosens it up. The punchline is to use little enough to not let gravity carry it to the glues in the driver.
Thanks for all the help and suggestions.

As for attachments from the rear of the driver, i can't find anything. As it is right now, i have limited access to getting into the cabinet though. This makes everything rather difficult. The funny thing is that this is an older subwoofer and all of the glue that was used on the binding post plate and ports ( 2 of them ) is still holding like it was freshly applied. I had a helluva time just getting into the box at all. I guess that they built things to last 15 years ago and didn't plan on having to do maintenance EVER : )

In case you are wondering, this is a big, old Sumo Samson that i found at a local shop. It is about the size of a big end table ( 29" long x 22" tall and 19" deep ) and weighs 120+ lbs. I can't believe how good of shape this thing is in, especially for its' age. Factory specs show 25 Hz - 120 Hz +/- 1.5 dB's and with the JBL that it has inside of it, should produce GOBS of output and take a real beating.

Due to the physical size and the fact that it is passive ( requires external amplification), they couldn't give it away to the "make it small, simple and hook it up for me" HT crowd. As such, i was able to snag it for $40 and they even helped me load it into the vehicle : ) At that price, i couldn't pass it up as i could sell the JBL ( which looks brand new ) for 2 - 3 times what i paid for it. Since my Dad doesn't have a sub and only has two 10's and two 8's in his HT mains ( how it must feel to be deprived ... ), i figured this would help him out : )

If worse comes to worse, i will probably end up cutting a section out of the back panel, installing a high quality "plate" amplifier and adding stuffing to the cabinet to make up for the loss of internal volume that the amp takes up. Does anyone have suggestions here in terms of a good plate amp ? Obviously, i'd like something that is well built, offers great control and a "good" amount of power. Clickable links would be nice and yes, i'd like fries with that too : ) Sean
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Gunbei: Maybe i was thinking of "bon voyage" due to the thoughts of having to hit the driver with a hammer / 2 x 4 to dislodge it : )
Sean,

It's doubtful that there is any other type of clamps, etc. used to secure this to the cabinet. The screws were likely the only thing, so you have essentially a glued in place, press fit driver. The cabinet front is going to get chewed up a bit as I think you will need to use more of the screw driver/block tactic. See if you can get a couple of other helpers to simultaneously pry around the edge. Striking the driver from behind is the absolute last resort, IMHO. The driver flange can be straightened after removal, no sweat. But if the basket is bent from hitting the magnet, you're screwed. So, is your rear access via the crossover hole? The only other approach I can think of, assuming the driver flange or part of it is visible from the back, is a curved flat of the same diameter. I hope I make this clear so just visualize a piece of steel bent to the flange diameter. This could be a 3 or 4 inch piece. You may need to weld a handle on this for striking purposes. Tap or strike this tool as you move it around the driver. Eventually it will work lose but will, like said previously, probably bring some cabinet out with the driver. Holy cow, this is like working on my hot rod and trying to explain concepts gets increasingly tough. Is there a way to attach bolts to the flange with the threads facing away from the cabinet front? If so, you can fashion some metal straps to the bolts and use a slide hammer. Good luck. I'm out of ideas.
Funny this is a subwoofer. I tried to take the driver out of one of my subs(HSU VTF-3) and gave up. The sub was brand new, I just wanted to take it apart because(the doctors are still working on this one)....

I removed the screws and after a little prying no luck. I gave up because it was brand new and I did not want to screw it up.

Maybe manufactures use heavy duty glue plus screws on subs..?

Marty
Was just thinking if you have or know someone who has one of those little steam machines. The glue or gasket material probably is so old it has dried out and is like concrete. Also there is an automotive gasket remover that might loosen things up if you are carful of the driver. Just an idea. TG
ya know, I had a buddy who had this problem once, i cant remember the brand, it wasnt anything spectacular.

He ended up putting a scewdriver through the driver and got so mad he threw the thing on the ground and broke the box open.

after careful inspection, it turns out that the subwoofer had had these little mushroom looking bolts on the back of the outer edge that anchor it down into the box. These would be put into holes cut in the box and slide through a groove next to the holes, and the "mushroom cap" would be anchored in.

turns out all he had to do to was unscrew the main screws on the outer edge, then twist the subwoofer about 4 degrees to the left and the anchors would hit reach an area large enough for them to pass through, anf the subwoofer would pop right off.

maybe try rotating that bad boy before using chemicals.

ive seen some furniture that fastens together in this manor.
Audiophanatik: I'll have to try that.

Corona: kind of "advanced but still gentle" thinking. I like it. A lot more work than a hammer and 2 x 4 though : )

All you other guys are gonna have me either high ( using chemicals ) or destroying the driver or cabinet : (

I'll see what i can come up with Friday as i have the day off. Hopefully, i can get this done and catch up on a few phone calls to "fellow Agoner's" that probably feel that i've "neglected" them and their problems. As you can see, i've got a few of my own.

Thanks for all the help so far and feel free to continue on : ) Sean
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I vote for destroying the cabinet! Good excuse to make a new, cooler looking one. :-)
Take care not to warp the frame of the driver as you try to shimmy it out. If you do, you may as well toss it in the trash. Dont ask me how I know :)

Also, if it is in a sealed enclosure you it may not be able to seal it back up after you replace into the enclosure.