Speaker Repair Kits - Yes or No?

[soundNERD]

I just got a pair of Marantz HLM-312B speakers for a buck at a garage sale. I was told they worked, and at first they did. But, the person must have had them stored inside a closet for a few years before they sold them to me.

I turn em on, they sound great, and I turn the volume up a little bit, but the second the bass hit i head this awful scraping sound from one. The foam surround had dried out and tore off of the frame of the woofer when the bass hit, and that sound was the voice coil scraping on the magnet.

They sounded suprisingly good, so I was disappointed that they broke.

I've seen rubber repair kits for under $20, and figured I'd just buy that and replace the old foam that dried out with rubber so I do not have to worry about it drying out again.

But, I've heard that they do not usually work and often make the speakers sound worse.

Has anybody here with old speakers with dried out surrounds tried replacing them, and if so, please let me know if they are worth it, or if I should just start looking for a good deal on a pair of 12's?

edit: almost forgot to mention the config of these speakers - 3 way, 3" tweeter, 4" midrange, 12" woofer, 165W peak RMS power handling.

Thanks,
Mike

[chipco3434]

Ya, do it. They work and it's a no- brainer.

[DSP_Geek]

Originally posted by chipco3434
Ya, do it. They work and it's a no- brainer.

They do work, but I wouldn't say it's a no-brainer. I've reconed a number of ElectroVoices and JBLs in my time, and I still followed the instructions carefully when using the PartsExpress surround kit to fix my Advents.

Hint: clear an area twice as big as you think you'll need and cover it with newspaper. That'll keep the spousal unit from complaining about speaker glue on the nice mahogany kitchen table.


Good luck,
Francois.

[xyrium]

If the surround is gone, what material are the cones made of? I'm assuming paper, and should probably be considered for replacement if you can get them while you're doing the surrounds.

I hope it works out, that would be a great find for a buck!

Rgds
Paul

[mpmarino]

Yep,
I did my old Infinity RS4B's and it worked out very well. Definitely worth the 20 or so bucks. It would probably depend what your cones are made of. Mine were poly so I was able to be a bit of a 'hammer head' scraping all the old surround off. I made a mess of a throw rug as the old glue seemed to turn to some sort of 'tar' with age. Also, the Parts Express kits came with glue that was supposed to work with all cone types, I couldn't get it to stick to the poly. The texture and smell reminded me of regular Elmers white glue. I ended up using Gorilla 'poly' Glue......worked like glue

[soundNERD]

The cones are thick paper. I think I could replace them, but that would change the sound of them a lot, plus cost more. And, I don't really need to worry about the cone being damaged during removal of the old foam because since it's so brittle, you literally only need to touch it and it falls off.

My ultimate plan was to buy a new tweeter and midrange and build some nice floorstanding speakers with the woofers. I was thinking to cross the marantz over at about 150-200hz and below to use them for deep bass, use a pair of pyle 10" woofers I have for the rest of the bass frequencies, then buy a midrange and a tweeter.

Thats just my idea, beyond that I haven't put much thought into it.

edit: Now, just thinking, if I'm going to be building some nicer speakers, maybe I might consider replacing the cones and surrounds with a poly cone. I searched on Froogle for 12" speaker cone and couldn't find anything. Does anybody know where I could find replacement cones?

Thanks,
Mike

[mpmarino]

edit: Now, just thinking, if I'm going to be building some nicer speakers, maybe I might consider replacing the cones and surrounds with a poly cone. I searched on Froogle for 12" speaker cone and couldn't find anything. Does anybody know where I could find replacement cones?

Thanks,
Mike [/B]

IMHO poly isn't necessarily an upgrade.

Also, I have heard ...(I have no real evidence) that replacement foam surrounds should last MUCH longer than the originals due to improved materials.

[DigitalJunkie]

Yea,they work fine.
I did a pair of 10" woofers in my speakers, and a pair of 8" woofers from some Advent's(I think?) my Uncle has.

It is a little tricky to get everything aligned again,just follow the instructions,and it should turn out fine.

(Hint: I used heavy paper wedged between the pole-piece and voice coil to make sure everything was centered and the coils wouldn't rub, before glueing the surround down.) -I think it mentions this in most of the re-foam kits.

[sprucemoose]

go for it! i have done several advent woofers: smaller, masonite ring, and metal-basket, and they work great! not a hard job at all.

sm.

[DSP_Geek]

Originally posted by soundNERD
edit: Now, just thinking, if I'm going to be building some nicer speakers, maybe I might consider replacing the cones and surrounds with a poly cone. I searched on Froogle for 12" speaker cone and couldn't find anything. Does anybody know where I could find replacement cones?

You'd have to cut loose the voice coil from the paper cone and get it aligned *exactly* with the new cone, while making sure the new cone is aligned with the suspension. The ElectroVoice recone kits worked that way. It's doable, but it's a pain in the neck, and not the sort of thing you want to try as a first project.

In any event, you still have to find a poly cone of the exact depth and diameter you need, no easy task as you've found. It's also not guaranteed the resulting frequency response will be what the crossover needs, either. These are $1 speakers, after all: at what point is it easier to just DIY from the ground up? Worst case these might be perfectly acceptable rear speakers.

I'd advise starting off with the surround kit and keeping the cones as they are. My re-surrounded Advents are 27 years old and the paper cones are still going strong. You might look at the crossover, however: if it has electrolytics, replacing them with better capacitors might be a fun project.