How to prevent mold growing on horn path?

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What coating do you use on the horn path?

Primer
1
20%
Paint
2
40%
Stain
0
No votes
Tung Oil
0
No votes
Duratex
2
40%
Bedliner
0
No votes
Other (Say it in your reply)
0
No votes
 
Total votes: 5

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chris_c_
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How to prevent mold growing on horn path?

#1 Post by chris_c_ »

When you're in an area with wet seasons, and you store these cabinets in non-air conditioned garages trailer, there's one huge problem. Mold will definitely start to grow on damp untreated plywood surfaces, such as, on the horn paths of the Tuba, Titan, and DR top cabs!

My first idea is to spray paint, stain, or primer, on the raw plywood of the horn path, before gluing on the last side of the cab. Obviously, after that last side is on, you can no longer conveniently access the entire horn path.

Question is, of the three coatings, spray paint, primer, or stain, which one is the most effective at preventing mold growth on the raw plywood?

Any other suggestions or experience on which coating to use, to effectively and economically prevent the growth of mold on the plywood of the horn path?
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DJPhatman
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Re: How to prevent mold growing on horn path?

#2 Post by DJPhatman »

If you are getting mold growth on the inside of your speakers, in Connecticut, you are somehow getting the interiors soaking wet. When I lived in FL (the most tropically humid place in CONUS), there was mold growing pretty much everywhere, except inside my speakers. They were all constructed from Baltic birch, and I am pretty sure that Bb is treated with a mold and mildew retardant. You have some other issue going on if there is mold present. My guess would start at the plywood used.

With that said, any of the above treatments, with the exception of bedliner, would stop any microscopic growth. I exclude bed-liner because of how it needs to be applied, and the dangerous fumes it puts off. I would never recommend OTC DIY bed-liner products, such as the Hercu-Liner line, because of the solvents used. The really useful bed-liners need to be sprayed on by a dealer, and usually need higher than normal heat to cure properly. This makes them NFG for application during construction.
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Accept the fact that airtight and well-braced are more important than pretty on the inside. Bill Fitzmaurice

chris_c_
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Re: How to prevent mold growing on horn path?

#3 Post by chris_c_ »

Thanks for your comment @DJPhatman !

Humidity levels often reach 90% in the spring and summer, for days at a time, and temps 70F-95F. Inside a cool garage, the moisture condenses out of the air into droplets on any surface including the horn path. This occurs probably 20-30 days per year.

The cabinets are basically stored outside - in a wood garage which is not climate controlled. There's black mold stains on the wood walls and posts of the garage near the concrete floor.

So far I haven't seen mold form on the plywood of the horn path, but I can only see the first 2 feet of the horn path, which was painted with black spray paint, after the cabinets were finished. The rest of the horn path (6 - 7 feet) was not painted because both sides were already attached, sealing it off from further paint.
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CoronaOperator
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Re: How to prevent mold growing on horn path?

#4 Post by CoronaOperator »

What about something like this, says 25 year lifespan in enclosed areas.
Built:
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2 x 29" width dual Lab12 Tuba60
6 x DR250 2510/asd1001
In progress:
2 x DR250 2510/asd1001
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himhimself
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Re: How to prevent mold growing on horn path?

#5 Post by himhimself »

That biocide spray looks interesting. If storing for a long time, you could perhaps make airtight covers for the mouth (certainly the horn path is well sealed) and drop a bag of desiccant in before closing them up. Kind of like what you could use in a gun safe. Just a thought...
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Bruce Weldy
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Re: How to prevent mold growing on horn path?

#6 Post by Bruce Weldy »

Not being facetious, but why does it matter? If you can't see it, you don't know if it's there. And if it is, I'm pretty sure it won't change the internal volume enough to affect the sound.

I wouldn't worry about it.

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byacey
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Re: How to prevent mold growing on horn path?

#7 Post by byacey »

If you really want to cover the horn path, I would use thinned Tremclad oil paint, sprayed through a spray gun, both from the horn entrance side, and the exit side. If you get enough of a cloud of paint traveling through there, it should coat the walls inside after multiple applications.
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DJPhatman
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Re: How to prevent mold growing on horn path?

#8 Post by DJPhatman »

CoronaOperator wrote:What about something like this, says 25 year lifespan in enclosed areas.
Actually, CO, this is much more effective at killing mold and preventing it from releasing its' spores (the dangerous parts). Ask me how I know! :wink: :shock:
chris_c_ wrote:Humidity levels often reach 90% in the spring and summer, for days at a time, and temps 70F-95F. Inside a cool garage, the moisture condenses out of the air into droplets on any surface including the horn path. This occurs probably 20-30 days per year.
In Florida, it is near 100% humidity pretty much all the time. At least 300 days a year. Average Mean Temperature is near 85*F. Black mold grows overnight. It is a very serious problem in FL. My equipment lived in an enclosed, plywood-lined trailer with no ill-effects. If you can't get past your fear of mold growing in the horn path, use the spray I linked above, through the removed driver throat hole, using a slow, mild, gentle fan to "blow" the mist through the horn path.
I know money often seals the deal, but seriously, quality is an investment, not an expense... Grant Bunter
Accept the fact that airtight and well-braced are more important than pretty on the inside. Bill Fitzmaurice

chris_c_
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Re: How to prevent mold growing on horn path?

#9 Post by chris_c_ »

@Bruce Weldy:
Not being facetious, but why does it matter? If you can't see it, you don't know if it's there. And if it is, I'm pretty sure it won't change the internal volume enough to affect the sound.

I wouldn't worry about it.
Black mold spores are poisonous to humans. I'd really rather not be spreading toxic black mold spores out of my kick-butt Tuba subs, onto the people on the dance floor, for people to breathe in. They could get sick, and then, there's a chance they could die from it.

If a few coats of spray paint or anti-mold spray could prevent that, then that's what we need to do.

himhimself:
If storing for a long time, you could perhaps make airtight covers for the mouth (certainly the horn path is well sealed) and drop a bag of desiccant in before closing them up. Kind of like what you could use in a gun safe. Just a thought...
They are stored, during the week, Monday-Friday, with the horn mouths open to the air of the garage. I guess you could make airtight covers, but making them truly airtight could be a challenge. It would require weatherstripping and nylon straps and/or metal clamps - which tend to gouge the nice surface of the other cabs, and/or get caught and tear people's skin and/or clothing.

Spraying paint or anti-mold stuff, would take far less effort, as long as it truly does a good job.
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David Raehn
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Re: How to prevent mold growing on horn path?

#10 Post by David Raehn »

You could do like some of the pro manufacturers do:

Make a caster board that clamps over the front.

I keep my T48s in pairs on a 24 x 48 cart placed mouth to mouth.
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Grant Bunter
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Re: How to prevent mold growing on horn path?

#11 Post by Grant Bunter »

If the problem is condensation leading to mould formation, is the solution to put the cabs in an area where condensation doesn't occur for the 20-30 days a year that's required?
Somewhere already climate controlled (presumably) like the house?

Have you noted mould formation in your cab(s) path(s)?

I'm extremely intrigued by this conceptually.
In order for condensation to form in the horn path, the horn path must be cooler than the area surrounding the cabs...
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chris_c_
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Re: How to prevent mold growing on horn path?

#12 Post by chris_c_ »

David Raehn wrote:You could do like some of the pro manufacturers do:

Make a caster board that clamps over the front.

I keep my T48s in pairs on a 24 x 48 cart placed mouth to mouth.
Have you really installed butterfly latches on the left and right sides of every T48 cab??
Have you made them airtight?
What have you added to the front edges -weatherstripping or something else - to give you an air tight seal?
Grant Bunter wrote: If the problem is condensation leading to mould formation, is the solution to put the cabs in an area where condensation doesn't occur for the 20-30 days a year that's required?
Somewhere already climate controlled (presumably) like the house?

Have you noted mould formation in your cab(s) path(s)?

I'm extremely intrigued by this conceptually.
In order for condensation to form in the horn path, the horn path must be cooler than the area surrounding the cabs...
1. House is too small bring 12-20 PA cabinets inside during the spring/summer.

2. The entire garage is cooler than the outdoors, by about 5C degrees, more or less. No sun, plus, a huge cool, concrete slab as the floor. So when outside air leaks in, and it constantly does because the garage isn't airtight and will never truly be airtight, the condensation happens close to the floor area, but sometimes you get droplets on the wooden walls, yet those are rather warm to the touch, since the sun is blasting them most of the time in the summer. It's another story on rainy days, then, it's 100% humid outside, and the air coming in definitely condenses as water drops. Which is the requirement for mold growth. Water on wood.

Not to mention - indoor events where it gets hot in there, maybe 1000 capacity event - and water condensation forms on the windows and walls - as well as on the untreated wood in the horn path of the speaker cabinets... perfect conditions to grow mold unfortunately.
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CoronaOperator
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Re: How to prevent mold growing on horn path?

#13 Post by CoronaOperator »

How about getting something a bit squishy and cheap like a sheet of chloroplast, place a cab on the ground mouth face up, place sheet of chloroplast, then place another cab mouth down over top. Let gravity seal them together. If the chloroplast doesn't seal well, glue strips of rat fur (speaker carpet) to the chloroplast or just use hardboard, its cheap.
Built:
17" width 10" driver Autotuba
2 x 29" width dual Lab12 Tuba60
6 x DR250 2510/asd1001
In progress:
2 x DR250 2510/asd1001
For best results, point the loud end of the array towards the audience

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