I’ve had my MX-5 for almost a year now, and despite lockdown preventing it being driven very much I absolutely love it. I can’t really fault anything. Oh hang on, there is one thing: the horn. I’m embarrassed to press the blasted thing. It sounds like something from ToysRUs. Doesn’t sound like something that should be fitted to a beautiful MX-5
Snail horn is the answer. Not expensive. A bit fiddly to fit BUT much better 
Audis have big loud horns, seem to operate randomly as well, maybe you need one of those.
My horn gets pressed every year during MOT 
You need one of these: Train Horn Prank : Hornblasters Shocker - YouTube
Or one of these: dukes of hazzard - general lee's dixie horn - YouTube
Go big or home.
Yeah, my NC2 is the same, it goes neep rather than blare
Don’t need to use the horn often enough to notice.
Conforms to local regs in Japan, I believe. My wife’s Honda CRV has the same weedy parp.
My NC1 has a pair of 150db (they recon, not so sure) Airhorns. It sounds like a truck horn. If you need to use the horn it needs to be heard.
Aaah, now that makes sense. Annoying though.
The alarm is a similar low volume too.
I fitted a set of these horns to my 30AE…
Air Horns for me, if I use the horn I really do want to be seen.
On the ND there is room for the pump and two horns inside the front right wheel arch liner. Lots of existing spots for attachment and the new live feed is straight across the the bonnet shut panel. The existing horn feed is right there for the relay activation.
Just be aware that there is a separate feed to each horn so remember to remove the second one.
If it is 150 Db , then I hope your insurance covers personal injury claims ,as that volume can cause permanent hearing damage . I had a punctured eardrum and lasting loss of hearing from a V10 F1 car , at about 20metres range , and a V10 is reckoned to produce 'only ’ about 140dB …
They are loud, but I doubt the figures
We all know that mummy taking her little poppets to school in an enormous off road capable SUV cannot see an MX-5. She has no idea what one looks like. If she is going to hit you, she is going to hit you, end of. There is a very slight possibility that within a range of about ten feet she may see you. Only slight but might be just in time to brake. Won’t stop her hitting you but it might make the damage slightly less terminal.
With this in mind the last thing you want is a loud horn. She will have no idea where the noise is coming from and will be looking in all directions in totally confusion. If she is looking sideways or backwards when she comes within ten feet of you any chance of last minute braking is lost.
You want to hear the horn on my big macho Defender, now that sounds like it’s off of Noddy’s car. 
I used to have 4x4 double cab (not in the UK but in a country you actually use them) and the horn was an embarrassing squeak, quickly figured out how to replace it and how to install a relay
It’s pretty much useless. I left my phone in my NC, that seems to set the alarm off, was very disappointed in the volume. I doubt I’d wake up in the night if it was going off.
Yes my NDs pathetic beep causes much family mirth and comparison to Brum’s! At least you couldn’t get into trouble with Russell Crowe (see “Unhinged”) as it’s impossible to do anything more than a “courtesy tap”!
I don’t know if I could go back to the Maserati air-horns I had on my Spitfire - they would clear the road of all central London traffic and pedestrians as they all fearfully looked round for the enormous American railroad locomotive that was apparently about to run them down!
