If my understanding of Calehedron's and Chainringtatto's description is accurate, it should sound something like this
@HaZ It sounds like the 3rd quirrel
Here is our palamar run and you can hear what it sounds like clearly
The benefits are when runnning higher boost pressure you dont have to run a heavy spring in the recirculating valve to keep it closed under high boost pressure which makes the valve more responsive which is why you get the chirping noises.
I noticed a bigger difference in my mini than in the A124 because the minis bypass valve is known to leak at high rpm/boost pressure.
It also sounded different on my mini when changing to a bigger turbo its not as chirpy and a more consistent woosh discharge.
I will update how it sounds on the A124 big turbo as soon as we get it installed.