So, hopefully again this is the right place to put this. I need help figuring out what plug-in my friend uses for reverb for siren synthesis in Audacity. He has told me that the first part comes with audacity, and you have to download the second part. Here is a link to one of his synths so you have an idea. He uses version 2.02 Thanks! https://www.youtube.com/watch?v=SBuiDFEktKA
You can’t just ask him what he used? Buy him coffee or lunch?
Koz
Sounds rather like one of my plugins.
If you search this forum (try a Google search including the search term: site:http://forum.audacityteam.org ).
I wrote a lot of posts, including some Nyquist scripts for simulating siren sounds 2 or 3 years ago - they will all still be on this forum somewhere (and they should also work in the current 2.0.6 version of Audacity).
Alternatively, buy him coffee 
Or brownies. Many of my musician friends will commit despicable acts for a double-fudge brownie.
Koz