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boethius
06-12-2018, 09:37 AM
I reluctantly picked up a set of L100s that have sat in an unconditioned shed for the last 20 years. They would otherwise have ended up in the garbage, so I paid the $5 and took them home. The cabinets were disintegrating and have been disposed of. I did remove the woofer, mids, tweeter, crossover, port and mid housing. They are all in surprisingly good shape, except for the highly offensive mildew odor. I have the ability to assess performance with the DATS v2 system, but no reason to believe there is anything wrong with any of them. The 123As do have white spots on the back of the cone, the front seems okay. The foam rings are in good shape, but I don't think they could ever be made acceptable. I need these to be completely odor free before I touch them without gloves and carbon filtered mask. My plan of attack is to wipe down with a weak bleach solution, all surfaces with the exception of the 123A front. Several days in the sun. If there is any remaining odor, then proceed with this:

Starbrite NosGUARD SG:

https://www.amazon.com/dp/B0053HPJ92/?coliid=I2UA9U8XOFGW6E&colid=3VUVG73N8WUBO&psc=0&ref_=lv_ov_lig_dp_it

This is intriguing and I just recently discovered it as an option and wonder if anyone else has ever used it on a driver, specifically the 123A, I'm afraid it might deteriorate or discolor the front, which at this point, is in very nice condition with minor yellowing.

I plan on dropping the woofers into a test box I have for zilch's econowave. I have the 220ti compression drivers with JBL waveguides and the <95dB crossover. At present, I have some Large Advent metal frame woofers and the sound is less than stellar, I'm curious to see how these will perform. Box is a bit on the small size (an Advent 5002 cabinet, I believe). There is always the possibility I get motivated to make some new boxes for all these drivers, I have everything I need except for the box measurements.

Mr. Widget
06-12-2018, 12:14 PM
No useful info to add, but lease keep us posted on your progress. This could be useful for others tackling such an ordeal.



Widget

rdgrimes
06-12-2018, 12:38 PM
Starbrite NosGUARD SG:

https://www.amazon.com/dp/B0053HPJ92/?coliid=I2UA9U8XOFGW6E&colid=3VUVG73N8WUBO&psc=0&ref_=lv_ov_lig_dp_it

.

That is essentially just bleach.

boethius
06-12-2018, 02:46 PM
An ozone generator might also work and they are available from Amazon for only about $70, I have one on order. People seem to have good results with them. I have had the drivers for 4 days now and a great deal of odor has already dissipated on its own (it was the cabinets, apparently, that were rank). I will report back on what I do and the results obtained. I have a very large nose, so know that my standards are very high as to end result, which is essentially no malodor at all as the level of acceptability.

rdgrimes
06-12-2018, 03:00 PM
Some direct sunlight can work wonders. The ozone devices also work great. Put the drivers in a small closet or the like with the generator and close it up for 2 days.

boethius
06-16-2018, 03:04 PM
So I settled on using Concobium Mold Control, rather than some of the bleach like products. Firstly, I wiped all the driver surfaces with a dry rag and small brush to mechanically remove as much dust and mildew as possible, then saturated a rag with the stuff and wiped on all surfaces. I did not apply to this to the driver cone faces, but did wipe the underside of the woofer and midrange with a damp rag. The idea with this stuff is to wet the surfaces thoroughly and then let it dry on its own. I then followed up with another wiping of all surfaces with a damp rag, as this stuff has TSP and will clean things up.

Some observations:

1- The foam ring on the woofer was covered with white spots, but three applications of the liquid and rubbing with some moderate force has them looking fine now. I thought I would need to replace these, but I will most likely not, since it looks like that would destroy the surround.
2- Mildewed cone surfaces will peel a bit of the paper when passed over by a damp rag and the area where the cone meets the spider was particularly bad, but I have pretty much removed all white spots, the back of the cone looks acceptable at this point.

I have them drying in the sun now and should be getting the ozone machine in a day or two to hopefully finish up removing all traces of odor. There are some oxidation spots on the aluminum, probably will get at those with wet 2000 grit paper.

Since there had to be a mishap, one of the tweeter leads broke off during the process, will see how that repair goes.

All in all, not a bad haul for $5. Next up is to test the drivers.