Sorry for the late reply. I was out of town.
Thanks for the suggestion. I have a can of water based polyurethane. Will definitely give it a try one day.
I haven't contacted Radian. They'll likely tell me to have the driver reconed. I'm in no rush to repair this coax. I have their studio version which uses a poly cone. They stopped manufacturing that some time back.
This coax was stored for many years in it's original packing. I think more than 20 yrs. The dust cap fell off with the rest of the cone. The cone literally dis-integrated in my hand. It was that dry and brittle.
The vintage Radian are noted for this problem. I honestly don't know whether they replaced the cones with better paper.
Another issue with the Radians is oxidation in the gap. The voice coil and the magnet is very close. Oxidation on the walls of the magnet will jam the voice coil. Maybe it's not oxidation but fungi like you said. I don't really know. All my other drivers don't suffer from this. I don't live beside the sea, so that cannot be the factor.
hahahaha....that's a good one.
I thought I could at least salvage the compression driver but it seems to be glued in.
The old formula of White Rain hair spray is or was an ultra-light sort of lacquer used on model airplanes to seal the wood. Sorry ladies but you'll have to hide your hair spray now. I don't know if the old 1970's-1980's White rain formula is still available.
Then else get an Eminence paper cone and forget your worries. Plus get 10 db or more efficiency on most woofers and up there with the mids. I see 30 year old guitar amps with the only degradation showing is sun exposure.
Then else get an Eminence paper cone and forget your worries. Plus get 10 db or more efficiency on most woofers and up there with the mids. I see 30 year old guitar amps with the only degradation showing is sun exposure.
Not really, but if you're still in doubt after all that's been posted, then buy the ones treated for outdoor apps. If you want to be concerned about something, UV does more long term harm IME, at least down here in the S.E., so have had to lightly [airbrush] shellac some drivers to bring back 'clarity'/'detail', especially old mobile audio drivers.
GM
Aqua Net, the original hair spray is what we used back in the '50s and at least the early '60s before I switched from U-control combat planes to slot car racing. Treated speaker drivers too and based on a fairly recent experience, it's still good for the latter and still the cheapest in my locale.
GM
I have a pair of 1990 vintage Cerwin Vega 15" PA woofers,
They are paper cones and were used/stored in the following climates
3 miles from the ocean (Italy) 2 years
1 mile from the ocean (Tampa, FL) 2 years in garage
Arkansas 7 years
West Texas 9 years (storage)
Kansas in garage 8 years
Cone degredation is none and they work fine just as they did 28 years ago. The accordion suspension is fine and they just keep plugging alone.
Built a pair of line arrays in my unheated/no AC garage and after 5 years of being cooked in the summer with enclosed garage temps of around 125F and winter lows slamming down to 20 below--those 40 paper cone mids shrug it off with no degredation. The woofer cones have a poly coat on the fronts but not the back of the cone and no issues.
Of course it is not really "paper", more of a long fiber pulp mixed with all sorts of things, chemicals and adhesives in reality. Don't worry about in home use, the PA speakers that are hauled around the world and beat on for years use paper cones without issue. Plenty of clock radios, boom boxes and old TVs used paper cones that have run for 20 years or more without any problems. The in ceiling speakers at malls run 18 hours a day for decades without reliability problems.
Now foam surrounds? Well--those turn to dust so avoid anything that uses them for long term reliability. I've seen 30 year old paper cones with rubber surrounds start to crack in the surround although the paper cone is fine.
The absolute worse place for a speaker is in a high humidity area with salt water around. Plenty of speakers in Tampa that had foam surrounds would rot out in 5 to 7 years so a great place to ask around for long term speaker reliability construction. Swamp humidity coupled with constant, daily rains in the summer with 6 months having the temps peak over 90F really turns everything into a mold machine.
Other options are to get waterproof professional drivers--the cones already have the treatment complete and should last you many decades.
They are paper cones and were used/stored in the following climates
3 miles from the ocean (Italy) 2 years
1 mile from the ocean (Tampa, FL) 2 years in garage
Arkansas 7 years
West Texas 9 years (storage)
Kansas in garage 8 years
Cone degredation is none and they work fine just as they did 28 years ago. The accordion suspension is fine and they just keep plugging alone.
Built a pair of line arrays in my unheated/no AC garage and after 5 years of being cooked in the summer with enclosed garage temps of around 125F and winter lows slamming down to 20 below--those 40 paper cone mids shrug it off with no degredation. The woofer cones have a poly coat on the fronts but not the back of the cone and no issues.
Of course it is not really "paper", more of a long fiber pulp mixed with all sorts of things, chemicals and adhesives in reality. Don't worry about in home use, the PA speakers that are hauled around the world and beat on for years use paper cones without issue. Plenty of clock radios, boom boxes and old TVs used paper cones that have run for 20 years or more without any problems. The in ceiling speakers at malls run 18 hours a day for decades without reliability problems.
Now foam surrounds? Well--those turn to dust so avoid anything that uses them for long term reliability. I've seen 30 year old paper cones with rubber surrounds start to crack in the surround although the paper cone is fine.
The absolute worse place for a speaker is in a high humidity area with salt water around. Plenty of speakers in Tampa that had foam surrounds would rot out in 5 to 7 years so a great place to ask around for long term speaker reliability construction. Swamp humidity coupled with constant, daily rains in the summer with 6 months having the temps peak over 90F really turns everything into a mold machine.
Other options are to get waterproof professional drivers--the cones already have the treatment complete and should last you many decades.
ATC Loudspeakers for example give a 5 year warranty on all of their speakers and the entire line has paper cone bass drivers.
Don't be so afraid .. metal domes can corrode and oxidize too.
My Wolverine (EV) 12" full range have survived the winter in my open to the weather garage without a problem. Here in Oregon the humidity goes up in the winter, way down in the summer - opposite of Ohio. They are no less than 50 years old.
The surround is the cone itself, corrugated. I did add my usual doping.
The surround is the cone itself, corrugated. I did add my usual doping.
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Personally I prefer paper to most other materials. I can't get the efficiency to work with my 8 watt amps in other materials. Paper sounds good at low volumes while with metal cones you really have to turn it up before it starts to sound dynamic.
With metal and plastic the manufacture just runs a sheet of it under a stamp which shapes and cuts it at the same time. Paper is more difficult because you need to pulp it, cast it in a wire basket, get it out of the mold, dry it, and trim it.
I live on Long Island which has very high humidity swings and my Fostax paper cones show no deterioration. When my low pressure steam boiler started going wonky and failing to turn off it was very humid in winter which caused some condensation on the walls and damaged them but not the speaker cones.
With metal and plastic the manufacture just runs a sheet of it under a stamp which shapes and cuts it at the same time. Paper is more difficult because you need to pulp it, cast it in a wire basket, get it out of the mold, dry it, and trim it.
I live on Long Island which has very high humidity swings and my Fostax paper cones show no deterioration. When my low pressure steam boiler started going wonky and failing to turn off it was very humid in winter which caused some condensation on the walls and damaged them but not the speaker cones.
I'm getting some 8" woofers made by Eminence and they use hemp in the cones,
They are green--I can yank people's chain and call it "the orgainic sound". Maybe the hemp will give better highs? I'll test them with Bob Marley and the soundtrack to up in smoke so they start off with something familiar during break-in.
Knowing that hemp is rot resistant as used for rope for many, many centuries--also used as a paper so it can last longer than I will live.
Just hope if I smoke a voice coil it won't be a cause for alarm. They will be protected from the sunlight in my living room by acoustic cloth so I don't expect any real world issues from the hemp/paper mix--I think they throw in other things. Somebody has to be at the bleeding edge, the guitar players seem to like them.
I think the Radian probably was attacked by more than humidity or dryness, pack in a box in the dark with many humidity/dry cycles might allow for something to invade for light housekeeping.
As far as the pooh thing--there goes another beloved childhood character down the drain! The next time I get stuck watching Winnie the Pooh, I'll be screaming when he gets his head stuck in the honey pot! My wife might get confused when I yell "Get your head out Winnie! Do it NOW if you are in Ohio!
I don't think they would let me out of the jacket even if I told them about anagrams--might earn a padded room attempting to explain. Thanks for the mental image!
They are green--I can yank people's chain and call it "the orgainic sound". Maybe the hemp will give better highs? I'll test them with Bob Marley and the soundtrack to up in smoke so they start off with something familiar during break-in.
Knowing that hemp is rot resistant as used for rope for many, many centuries--also used as a paper so it can last longer than I will live.
Just hope if I smoke a voice coil it won't be a cause for alarm. They will be protected from the sunlight in my living room by acoustic cloth so I don't expect any real world issues from the hemp/paper mix--I think they throw in other things. Somebody has to be at the bleeding edge, the guitar players seem to like them.
I think the Radian probably was attacked by more than humidity or dryness, pack in a box in the dark with many humidity/dry cycles might allow for something to invade for light housekeeping.
As far as the pooh thing--there goes another beloved childhood character down the drain! The next time I get stuck watching Winnie the Pooh, I'll be screaming when he gets his head stuck in the honey pot! My wife might get confused when I yell "Get your head out Winnie! Do it NOW if you are in Ohio!
I don't think they would let me out of the jacket even if I told them about anagrams--might earn a padded room attempting to explain. Thanks for the mental image!
Just wanted to chime in. I have a penchant for composite drivers like the famous Focal W or Rohacell based drivers are among my faves.
However, when it came down to building my last main speakers, I went with Scanspeak. They use kind of a composite. It's 2 layers of paper glued together and sliced open. Could not be happier.
Best,
E
However, when it came down to building my last main speakers, I went with Scanspeak. They use kind of a composite. It's 2 layers of paper glued together and sliced open. Could not be happier.
Best,
E
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