Suggestions. Need weather-proof speaker.

[nharrer]

Hi.

First off, I am an electronics beginner and hobbyist. So I probably don't know what I am doing .

TL;DR: I need a speaker that can withstand outdoor conditions (humidity, rain) and temperatures down to about 0 degree C. What can I use?

Long story: My parents live in the countryside and my mom has a nice garden. There are a lot of deer around and they come in at night an eat delicate stuff like rosebuds. The more precious the plant, the more likely they eat it. She has tried a lot - horn shavings, all kinds of hair, sprays, dangling CDs and bells - you name it. Two things are out of the question. Fencing in the property or doing something inhuman to the deer. But she found out that one of the better methods is having a radio outside during the night and putting on talk shows. They can't stand humans talking at all.

So I thought I build her an improved version. I want to make a battery powered box with a motion sensor, which starts flashing bright light and playing sound (voices) when triggered. The size of the box is not so important. However, based on the outdoor lights I fix on a yearly basis, I know that weather and electronics don't play well together at all. I think I will use an IPx6 rated enclosure and probably conformal coat or even pot the electronics. The motion sensor is an HB100 Doppler Radar Module which I used successfully in other projects. It's reliable across temperature and light conditions. And it can be placed inside the enclosure where it is well protected (the thin plastic of the box is basically invisible to it).

But I am still pondering about what to use for the sound. A piezo element is to faint and sounds horrible for sounds like voice. And I had bad experiences with a regular speaker which was used in a well protected outdoor area (no rain and no wind). The outdoor humidity alone made it fail within a year. And putting the speaker inside the airtight box makes it almost silent. It doesn't need to be very loud however. It's hard for me to put this into numbers. I would say around 40-50 dB max? Like the volume you'd set a radio while you are studying or reading. It should not bother the neighbors at night, but still be audible to the deer (they have excellent hearing anyway).

I would be grateful for any suggestions about what can be used. It will be outside day and night from spring to fall (not winter though). So temperatures down to at most 0 degree C. And rain is common here in Austria. Oh, and since it'll be battery powered, power consumption is not neglectable (it won't be on all the time though - only for a couple of seconds to a minute when motion is detected).

Also hints and links about how to make electronics weather proof will be welcome.

Thanks and regards,
Norbert

[Zero999]

As far as the speaker is concerned, one with a plastic cone should do the job. It won't sound as good as a paper cone speaker but it will be much more weather resistant. Another option is a horn speaker, designed for outdoor PA systems, which will be much more efficient, but again have poorer sound quality, than even a plastic cone speaker.

Note the sensitivity specification for the horn vs cone speakers. The cone speaker has a sensitivity of 86dB@1W, whist the horn speakers produce >96dB@1W, which is 10 times the sound, for the same input power: the dB scale is logarithmic, going up by 10, means 10x the power. The downside is the frequency response of the cone speaker is better, especially at lower frequencies, which travel further. Cost is also a factor, with the more expensive horn speaker having a better sensitivity and frequency response, than the cheaper horn speaker.
https://www.rapidonline.com/visaton-2110-4-ohm-white-10cm-waterproof-speaker-35-2905
https://www.mouser.co.uk/ProductDetail/Visaton/DK-115-S-8-ohm?qs=sGAEpiMZZMuTkJYgZlQcSSXjUNenqzcecWTdQUXTWNE5DZ52KRKe4Q%3d%3d
https://www.mouser.co.uk/ProductDetail/Mallory-Sonalert/PH-180Q?qs=sGAEpiMZZMuTkJYgZlQcSSlXFR%252bHilBy9SGdcQY5Usk%3d

How about keeping the electronics indoors and running cables to the speakers and sensors? If the cable run to the speaker is long, then use a 100V speaker and add a step-up transformer to the output of the amplifier. Boosting the voltage means a the cable doesn't need to be as thick, as the current will be lower.

[b_force]

I don't understand were the idea is coming from thar plastic (poly) speakers are lower quality.
I know quite some very high quality professional drivers with plastic cones that perform extremely well.

That being said, I don't think deer will be that picky.
There are a lot of outdoors waterproof PA speakers available.
If it's not to difficult to run wires, I think i would also go for something like a 100V system.

Re-entrant horns are very efficient, but their frequency response is very limited. So human voice don't sound very natural. The question is if deer pich that up.
Also they bundle the sound (directivity) quite a lot.
So you run the risk of needed more of them to cover all areas.
On the other side they are very robust and can withstand a lot of abuse from the elements.

[Zero999]

I don't understand were the idea is coming from thar plastic (poly) speakers are lower quality.
I know quite some very high quality professional drivers with plastic cones that perform extremely well.

You're right, but those sorts of speakers also have a foam or rubber surround, which is not very weather proof. After a year or so outdoors it will perish, causing it to sound even worse and allow water into the coil and terminals, resulting in corrosion and total failure. 


https://cpc.farnell.com/unbranded/55-1600/woofer-polyprop-cone-4ohm-6-5/dp/LS00425?mckv=sOe9UCXSQ_dc|pcrid|224680571758|kword||match||plid||slid||product|LS00425|pgrid|46864214357|ptaid|pla-374151146812|&CMP=KNC-GUK-CPC-SHOPPING&gclid=EAIaIQobChMIgrfom9Ds3QIVzL_tCh20_goMEAQYBCABEgK1S_D_BwE

The type I'm talking about have a single piece of plastic for the cone, with a corrugated surround and are more durable, but don't sound as good.
Here's what the naked driver looks like.

https://cpc.farnell.com/visaton/sl-87-wpm-8-ohm/3-3-inch-waterproof-speaker-8/dp/LS04837?mckv=sHbsm49Tp_dc|pcrid|224680571758|kword||match||plid||slid||product|LS04837|pgrid|46864214357|ptaid|pla-374151146852|&CMP=KNC-GUK-CPC-SHOPPING&gclid=EAIaIQobChMI1tPS68_s3QIVS7TtCh0MZwEuEAQYAyABEgJBufD_BwE

[vk6zgo]

You can buy speakers which are designed for use outdoors or on board yachts.
These are good, if a little costly.

The security gate intercom system in my old work originally used car stereo speakers, which lasted quite well, but eventually, they all failed.
We replaced them in the mid 1990s, with the "outdoor" types speakers, mounted in separate plastic boxes, as they were larger than the originals.

I left that job in 1999, but they seemed to still be OK when I visited 10 years later.
For your application, it might be cheaper & easier to grab some reasonable quality 3" car stereo speakers, &
just change them when/if they die.

The car ones are fairly moisture resistant, as they are subject to condensation when the car is parked in cold & wet weather.

[The Soulman]

Get one of those rock shaped loudspeakers?

https://www.google.nl/search?q=rock+loudspeakers&source=lnms&tbm=isch&sa=X&ved=0ahUKEwi9uoGL7OzdAhWIYlAKHekzCxoQ_AUICigB&biw=1600&bih=789

[nharrer]

Wow. Thanks for all the great suggestions. I'll probably just go with a cheaper plastic cone type for now.

However, I googled around about 100V systems. Might be an interesting topic to play around with. How about safety. 100V sounds a bit scary to me.

[mac.6]

100v system use output transformers, so they are not referenced to ground.

[drussell]

There are many speakers designed for use in outdoor environments.  Searching for things like "Patio" speakers or "Marine" speakers will find you plenty of examples, both bare driver and assembled units.

There are also plenty of outdoor "Garden" or "Landscape" speakers, usually disguised as something like a rock or simple green plastic doodads to blend in with garden greenery.  While ones that are high fidelity can be rather pricey, even a very cheap Chinese example of those would probably suffice and be durable enough for your intended application.

Examples:

https://www.parts-express.com/cat/garden-landscape-outdoor-speakers/96
https://www.parts-express.com/cat/patio-porch-deck-outdoor-speakers/97
https://www.parts-express.com/cat/marine-speakers/438

[Zero999]

100v system use output transformers, so they are not referenced to ground.

Yes and I believe 100V is the maximum, not the continuous voltage, which will depend on the sound level and volume setting. It's much safer than the mains being isolated from earth and not being at 100V continuously, but it can still shock, so more safety precautions are necessary than for a less hazardous voltage such as 24VDC.

[Jeroen3]

Did you consider surface transducers? You can make the entire box speaker.
https://www.sparkfun.com/products/10975

Otherwise just use those omnidirectional garden speakers. Camouflaged as a rock, or green bucket. There will be space enough in the enclosure to mount your detection radar and electronics.

[b_force]

Did you consider surface transducers? You can make the entire box speaker.
https://www.sparkfun.com/products/10975

Otherwise just use those omnidirectional garden speakers. Camouflaged as a rock, or green bucket. There will be space enough in the enclosure to mount your detection radar and electronics.

They are called distributed mode loudspeakers (DML) or sound exciters.
It basically means you can make a loudspeaker with any kind of surface.
One of the disadvantages are that they are typically for in house only.
Very fragile construction.

My pick would also be something easy of the shelf, partsexpress has a whole section with these outdoor speakers

https://www.parts-express.com/cat/garden-landscape-outdoor-speakers/96

[Karlo_Moharic]

Install airhorn (you can buy electrical airhorns of ebay) , that will scare the shit out off deer , specially if you can find train airhorn (total overkill , but amazing idea if you want to wake whole neighbourhood)

[drussell]

The OP probably wants to scare only the deer, not mom... 

[Teledog]

Have the same problem here with "critters" ie:  raccoons, cats, etc.
Using/testing RCWL-0516 modules
Have the latest triggering;
a: one of those sonic annoying beepers via a 2n7000 FET
AND b: a 1W LED/180R  via a IRLZ44N FET
{Put a 100k between the Gate/Source}
Running it off a cheap 12V 500ma wall wart.
Any critter (rat, mouse, human) comes within 15' and it beeps & lights for a few seconds!
Cheap like borscht!
Have it covered with a dollar/pound store plastic garden cloche - 3 for a buck!
So far so good! No wrecked garden anymore! (it is fall now here though, ..sigh)
G'luck!

[drussell]

I'm thinking I should try rigging up something like this for my garden next summer.  For the past 10 or 12 years I lived here there was always one of the neighbors with an "outdoor" cat which kept all the other critters away from the garden.  The past couple seasons since the last person with a cat moved away I've had constant problems with carious critters, though most of the damage seems to be mostly from birds.

One time I went back outside (I had only been inside for a few minutes, even) and there was a rabbit pulling a carrot out of the ground, a whole flock of birds pecking at the poor little top shoots on the peas and a squirrel digging around in in one of the tomato pots.  None of them seemed scared of me, either, until I tried to run after them.  Then they just bounded (or flew) away 20 feet.  I can't even imagine what happens when I'm not home. 

No wonder my last couple have have been so meager instead of a nice bumper crop!

I wonder what kind of noise I need to make to keep those birds away...  Hmmmm...