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View Full Version : L150's woofers glued in!



jay
04-17-2005, 08:51 AM
Hi folks, not long ago I scored a pair of L150's in decent shape. I thought everything was fine until on a tip from fellow forum member 'thoots' I tried to remove the passive radiators in order to get the 'extra' weights off.

It was then that I found that the passives were glued in with silicone adhesive! I tried to sneak in by pulling a woofer - same story. It seems that Brownell's of Portland Or. where they were serviced, has done their dirty work again. http://audioheritage.org/vbulletin/images/smilies/biting.gif

So here I am with an ultra-boring sounding pair of L150's that I can't do anything with.

Can anyone suggest a nondestructive way to get the woofers and passives out? The gap between the drivers and baffle is so tight that the odds of getting any GooF Off or other chemical in there is slight. I don't want to damage anything by literally prying on the baffle board.

I'm stumped.

Jay

Robh3606
04-17-2005, 09:23 AM
What might work is fine bare wire. If you can get something like a light gage quitar string rock it side by side and pull it towards you at the same time once you get under the frame. You may be able to cut the silicone and break it's grip. Then you can get something under the frame. Figure the 4 mounting screws will not allow you to really cut all the way so you can try with them in as a safety or remove them so you can get closer to the frame. Be careful you can slice your hands and fingers up doing this or damage the driver if you slip. The other way would be a putty knife but the blade may be too fat to get under the frame without maring the baffles or frames. You could try getting just a box knife blade under them but then you are asking for some nasty cuts trying to bare hand sharp blades like that and of course you could mess up the baffle.

Good Luck

Rob:)

porschedpm
04-17-2005, 12:36 PM
You may want to contact Brownell's in Portland to see what they suggest.

guest
04-17-2005, 02:40 PM
It was then that I found that the passives were glued in with silicone adhesive! I tried to sneak in by pulling a woofer - same story. It seems that Brownell's of Portland Or. where they were serviced, has done their dirty work again. http://audioheritage.org/vbulletin/images/smilies/biting.gif

Can anyone suggest a nondestructive way to get the woofers and passives out? The gap between the drivers and baffle is so tight that the odds of getting any GooF Off or other chemical in there is slight. I don't want to damage anything by literally prying on the baffle board.

I'm stumped.

Jay
Hi Jay, I'm Dave. No dilemma, piece of cake.http://audioheritage.org/vbulletin/images/smilies/applaud.gif CAREFULLY knock out the wire connector plate and come through from the back side? A 3 lb hammer, solid length of wood and some tenderness can get you what you want. I'd use a 5 gallon pail with lots of padding on the rim then lay the whole cabinet face down on the rim of the bucket with the 12" able to fall into the bucket. Padd the inside of the bucket with a blanket or similar so you don't damage the passive when it does break free. The padded rim of the bucket should give support to the baffle around the 12" so you won't cause any damage there. Make sure you take the attaching screws out before you start(no insult intended.) Gently tap all the way around the basket, USE GOOD JUDGEMENT!!! I didn't say it be easy, you'll obviously need to support the rest of the cab to keep you square with the bucket but there is ALWAYS a way. You could easilly re-attach the connector plate when you're done, they're only stapled in. Then again, if your dangerous with tools, you might not want to risk it http://audioheritage.org/vbulletin/images/smilies/banghead.gif . If you need a detailed walk through the process email for me for phone #'s and we can chat.
Harmonies, Davehttp://audioheritage.org/vbulletin/images/smilies/blink.gif

Zilch
04-17-2005, 03:42 PM
Is there a counterbore on the baffle, that is, is the woofer recessed into the baffle a little, or is it flush?

You'll not break a slicone seal by pounding on the driver frame from the back. Nope.

There's no solvents that'll do it, either, that I know of, and heat won't soften it. You'll have to cut it.

Soon as you can, insert a tapered prying tool, like a painter's 5-in-1 tool, between the frame and the baffle. Keep pressure on to stretch the silicone as you go around with a utility knife or NEW single-edge razor blades, maybe.

You want to cut the silicone itself, not the baffle, of course.

Your hardware store has a wire saw to use as Rob suggests above, as well, like a guitar string with "teeth," rings on the ends to pull it....

Titanium Dome
04-17-2005, 09:31 PM
Can you get us a closer look at the actual problem area? Your picture is too far out for any useful observation. I'm not familiar with how the drivers on the L150 are attached to the baffle.

OTOH, I'm familiar with removing silicone adhesive and things that are adhered to it, including glass, ceramic, tile, wood veneer, plastic, plastic laminate, stainless steel, chrome, brushed aluminum, and fibreboard.

guest
04-18-2005, 08:26 AM
You'll not break a slicone seal by pounding on the driver frame from the back. Nope.

There's no solvents that'll do it, either, that I know of, and heat won't soften it. You'll have to cut it.

Soon as you can, insert a tapered prying tool, like a painter's 5-in-1 tool, between the frame and the baffle. Keep pressure on to stretch the silicone as you go around with a utility knife or NEW single-edge razor blades, maybe.

You want to cut the silicone itself, not the baffle, of course.

Your hardware store has a wire saw to use as Rob suggests above, as well, like a guitar string with "teeth," rings on the ends to pull it....

Zilch is right, you won't get it out by "pounding" on it, NOPE, but then interpreting "Gently tap all the way around the basket, USE GOOD JUDGEMENT" as instructions to pound on your passives would explain why Zilch is only allowed to play with plastic hammers nowadays...YEP http://audioheritage.org/vbulletin/images/smilies/applaud.gif
A small bottle jack strategically placed between the back of the passive and the inside back of the cab can be incrementally adjusted to take up any slack against the stretch of the silcone as the passive moves out. The silicone will not simply tear. Reaching in and cutting any of the silicone you can will be to your advantage. It will stretch until the paint and pieces of partical board in the counterbore (that the silicone is adhereing to) break free and the passive will come out without consequential damage to the baffle. There is no quick fix for instant gratification, it is a process requiring patience and ingenuity. The instant gratification will come when you have tweaked your 150's to complete satisfaction and sit down in front of them for a delightfully tantilizing evening of your favorite tunes.
The wire saw idea is pretty good but you still have to get to the backside of the passive to hold the end of the wire and silcone is very uncooperative as well as the high probability of scraping both baffle and basket or even cutting into them on the exposed front where it matters most. http://audioheritage.org/vbulletin/images/smilies/bouncy.gif

4313B
04-18-2005, 09:03 AM
So here I am with an ultra-boring sounding pair of L150's that I can't do anything with.

Can anyone suggest a nondestructive way to get the woofers and passives out? The gap between the drivers and baffle is so tight that the odds of getting any GooF Off or other chemical in there is slight. I don't want to damage anything by literally prying on the baffle board.

I'm stumped.

JayI'm stumped. Why are they ultra-boring?
If they're that boring busting the drivers out and reducing weight on the passive radiators isn't going to make them the life of the party.

To be blunt - build new mirror imaged boxes and build them to at least L150A specs. eBay the 033's and pick up some 044's. eBay the N150's and pick up some N96's (L96), N112's (L112), N150A's (L150A) or build a pair of charge coupled 3113B's (4313B) or even 3109's (4411). Someday down the road if you find a pair of 120Ti's put those components into your "new" mirror imaged L150A boxes. They're a bolt-in.

jay
04-18-2005, 09:32 PM
Guys,

I'm incredibly impressed with the replies in this thread! Heck, I figured the 150's were at the end of the road, but you've given me new hope with your amazingly clever ideas for removing the woofers!

Titanium Dome, I've attached a 'closer' pic. I hope it's useful, the light here isn't good. It shows that both the woofers and passives are very tight within their baffle recesses.

Oh, and here's something weird -- when I bought these, the seller claimed the woofers to be D123's! I'm a tad skeptical as they appear to be the correct 128h's, or something near to it, but I'm no expert.

Giskard, the 'boring' sound I'm referring to is apparently the stock L150 and 150A sound. As I mentioned, it was member "thoots", an L150A owner, who put me on to these, and in conversations with him, he related that indeed his L150A's were thin, distant and 'boring' too, when stock, but merely removing the passive weights uncorked the hidden power of the design. Heck, I've heard his, and even above my 4333's, his 150A's rank as the best speakers i've ever heard! It was "that sound" that I was hoping to find with my L150's. As is, in stock tune, they sound very 'east coast' dull, or, "accurate" if you want to put it that way, but in my opinion have they little to recommend them.
In other words, they don't have that L100 magic! :D
Oh and thanks for the recommendations for improvement! I've saved them in a little file or future reference. :)

Once more, "thanks" guys. There's a lot to like in this forum!! :p

GordonW
04-18-2005, 09:40 PM
One thing that sticks out, from the picture- somebody has replaced the dustcaps on the 128H woofers, with the 4.125" dustcap for a 2235 or 124H, instead of using the 3.2" dustcap stock for the 128H.

I doubt it will make a huge difference in the sound, but it's definitely not stock. Those dustcaps are made to mount right on the voice coils; having the cap mounted up on the cone COULD possibly change the sonics, due to different coupling of cone motion into the dustcap.

Regards,
Gordon.

Zilch
04-18-2005, 11:15 PM
D123's? Not with foam surrounds they aren't....

4313B
04-19-2005, 05:45 AM
As is, in stock tune, they sound very 'east coast' dull, or, "accurate" if you want to put it that way, but in my opinion have they little to recommend them.Well, you're not the only person who doesn't particularly care for those L110/L150/L212/L250 filters. I've heard plenty of others say the same thing over the years. If you like thoots' L150A's better then you should at least look for the N96/N112/N150A filters if nothing else.

Schematics for reference.

Adding or removing mass from the PR is the same as lengthening or shortening a port/duct and will only affect the bass bump in the first octave or two.

pmakres1
04-19-2005, 08:51 AM
One thing that sticks out, from the picture- somebody has replaced the dustcaps on the 128H woofers, with the 4.125" dustcap for a 2235 or 124H, instead of using the 3.2" dustcap stock for the 128H.


I thought that dustcap looked big..Now that I look at the closeup, you can see how close the edge of the cap is to where the coil leads attach to the cone. Very astute GordonW!

Peter :)

Titanium Dome
04-19-2005, 11:13 AM
Guys,

Titanium Dome, I've attached a 'closer' pic. I hope it's useful, the light here isn't good. It shows that both the woofers and passives are very tight within their baffle recesses.



It's a better look, though a really tight shot would be more informative. Anyway, here are some caveats, then two methods I've used.

CAVEATS:

1) NO pounding. Banging around can cause things to get out of alignment, can create tiny fractures, and can deform things.

2) Be careful not to bend or warp the frames; once done this is difficult (impossible) to undo.

3) Protect all surfaces, baffle and speaker alike. Put blue 3M tape around the opening. Get a thin, flat piece of wood, metal, or plastic to lay against the baffle (on top of the tape) at any point where prying might take place. Scribe and cut out a circle of heavy cardboard or other material to place over the open face of the speaker to stop any errant tools that get out of hand.

4) Make sure the speaker enclosure is lying on its back on the floor. Yes, gravity will work against you, but when the driver pops out, that's a good thing.

5. Wear goggles.

6. Bear in mind you try these methods at your own risk, and I am not guaranteeing any result.

METHODS:

1. Procure four or five bicycle tire levers. These are the flat, angled levers used to remove and install the tires on the rims. Preferably get the plastic/nylon ones to reduce the likelihood of damage, but if they bend under torque, you'll need the steel ones. Working with an assistant, place two of the levers about three to four inches apart and work them down to below the speaker frame's edge and apply pressure to the other end of the lever to create a lifting force, but DO NOT attempt to actually pry the speaker free yet. Just get some lifting pressure on it.

While keeping the pressure on those levers, insert two more levers, about three inches outside of the two already inserted. (This is why you need an assistant.) Follow the same procedure as above, then when all four levers are sufficiently engaged, DO attempt to pry the speaker free by applying maximum pressure in unison. You should hear a ripping/tearing/popping sound as the adhesive fails. Then continue around the frame with the separation.

Note that you might need to place small blocks under the levers as fulcrum points if the lift is not sufficient. From the picture, I can't tell anything about speaker installation depth in the baffle.

Also, let me be honest and say you've likely to get a few edge dings around the speaker hole with the first few insertions. These should be minimal if you follow the caveat instructions.

I've used this successfully on more than one occasion.

2. This second method is less elegant and more dangerous, but I used it once with great success. You'll need a sturdy board that is about 2x6x?, with the ? being the length needed completely to cross your baffle from side to side. You'll need two wooden blocks, say 2X6 scrap pieces that are maybe two to three inches in length. Additionally, you'll need four bolts, a hydraulic jack, a shallow steel cup with four holes drilled equidistant around the edges, four equal lengths of 200# nonstretching cable, and eight small cable clamps. Essentially you'll be making a speaker puller.

I think you can determine how to assemble the thing yourself: one block on each side of the driver, board on top of that centered over the driver, jack centered on that, cup on top of jack screw, cables threaded through holes and clamped to equal lengths and run around bolt heads and clamped.

However, the bolts are key: they must have a thread diameter that is larger than the diameter of the speaker frame's four screw holes, but a shaft diameter that is less. You must find bolts (NOT screws) that have a fairly coarse thread with the widest possible shaft diameter that will fit. The bolts must be turned into the holes a few turns so the threads grip the frame on either side of the hole. All four bolts must be installed first, then secured to the cables. After everyhting is centered, jack the speaker out of the enclosure.

Actually, one of two things will happen: the speaker will pop out cleanly and quickly (my experience) OR the holes will distort, the bolts will pop out, possible striking you in the eyes and blinding you (wear goggles), and your frames will be warped (not my experience, but definitely possible).

porschedpm
04-19-2005, 11:36 AM
If the woofer is not recessed into the cabinet I would certainly recommend carefully going around the circumference of the speaker with a utility knife to try to cut through the silicone. As Titanium suggested use the blue masking tape or equivalent to protect the cabinet. The piano wire method may also work.

Just a thought. After bolts are installed as described by Titanium Dome above (and Giskard who suggested 1/4"x20 bolts) can a stout rod or sturdy broom stick or even a 2x4 be used to twist the speaker free. In other words place two bolts in two of the speaker mounting holes, each 180 degrees apart from each other, Then span the broom stick accross the face of the woofer so that it lays to the left of one bolt and to the right of the opposite bolt. Apply torgue at the end of the broomstick so that you would be twisting the woofer free. I've never tried this but it seems it might work if the silicone is first weakened by cutting with the utility knife. Of course it all depends on how sturdy the bolts are in the holes. Plus you wouldn't want very much of the bolt sticking out the other side of the hole since it would work against you when you go to twist the speaker.

And as always, wear protection.

4313B
04-19-2005, 11:56 AM
I just double-checked the 1/4-20 bolts on four different 128H frames. The bolts screwed right in to two of the frames and were too small for the other two frames...

jay
04-19-2005, 12:45 PM
Thanks G, that helps! :yes:

Jay

porschedpm
04-23-2005, 06:42 PM
Hey, Jay. Did you ever get the woofers out. If so how'd you do it.

jay
04-24-2005, 08:52 AM
Porschedpm,

Uh, well it's like this...

First, a friend dropped off a pair of Phase Linear P-530's for a long term listening session. If you're not familair with them, they're kind of an 'improved' Pioneer HPM-100, but with Pioneer TAD type drivers. They do sound great, so that's been a distraction.

Most critically though, I discovered that one L150 has two stripped screw "T-nuts", you know, the part that's in the MDF and accepts the hold down screw? One stripped T-nut is in the woofer, one in the passive!
So even if the silicone sealer came unstuck, there's still the problem of getting either of those loose.

Will it ever end?.....:banghead:

mech986
04-24-2005, 09:55 AM
Hi Jay, Sorry to hear of your dilema. At this point, it really sounds like you're going to have to come from the rear to get access to the screws. I'll bet the screws that are stripped (or that the T-nut has lost grip with the baffle) are one of the lower ones on each driver. I was going to suggest taking the tweeter out but then you'd need a long arm to reach down to the top woofer screws and you still wont get to the lower woofer screws.

Looks like you'll have to knock out the rear connector panel first to see if that gives you enough access to the woofer and passive screws/t-nuts. A well placed vise-grip on the loose t-nut then braced on the frame may allow you to get it loosened without a helper, otherwise engage someone to help - one to hold the grips and the other to unscrew the driver - you should make this one the first to come out. If you can then take out the driver, then access to the passive will be easier. STill, you do have the problem of breaking the silicone seal.

Hope this still encourages you.

Bart

Titanium Dome
04-24-2005, 09:56 AM
Well, that sucks. :biting:

If you can get the thin blade of an upholsetry tack remover under the head of the screw, then use the blade's offset to force the screw upward as you turn it counterclockwise. Again, protect all surfaces and your eyes. This may require some serious pressure to get the nut's lateral friction high enough that it will stop rotating and release the screw.

DMMD
04-24-2005, 10:04 AM
STOP!

Don't go in from the back plate or bang on it. Most of the post terminals are mounted to the crossover on the L150/L150A. I did see one pair with the crossovers mounted near the top of the cabinet... just check for the location first- that's the point. Don't assume a swift tap will just pop the staples and give you an armhole like on many of the small monitors.

Doing so on my L150A cabs would be a disaster. I'd experiment with the passive first... it's less valuable and more forgiving. :o: Good luck.

The putty knife would have worked.... if only the T-nut was still solid!