The science of The Archers' studio
It's a special bit of radio magic. The BBC's most claustrophobic studio is actually designed to replicate wide open spaces.
The radio drama studio here at BBC Birmingham is home to regular dramas The Archers and Silver Street as well as one off productions. As someone once said working in radio is much more fun than working in television because the pictures are better.
To help create those pictures the creators of radio drama use plenty of clever tricks. I shouldn't give too much away but I can reveal when lambing starts at Home Farm in The Archers it's not a live birth it's actually a rubber glove and some yogurt.
The main radio studio contains a variety of floors and stairs and even an Aga and sink to help create all the noises a drama might need.
But the big challenge is creating the ambient sound of a large farmyard or even the wide open spaces of the Borsetshire countryside.
And that's where the smaller, more claustrophobic part of the studio comes in. Once inside plenty of soundproofing completely deadens all noise. It is a bizarre experience. Even in our quietest moments we're still surrounded by sound and that sound bounces from surface to surface to surface. Take that away and you feel cut off from the rest of the world.
This strange effect is down to the pyramids of foam on every surface which effectively absorbing the sound energy. The sound waves travel into the millions of tiny holes in the foam where they are absorbed before the sound can bounce off a reflective surface. Using pyramid shapes means you can maximise the surface area of the foam making it even more potent.
The advantage for a drama director is you can remove the audible and detectable sense of being in a smallish studio completely. And then replace it with a completely difference audio landscape from farmyard to open countryside and beyond.
As a final twist there's the "acoustic snail". The soundproofed studio twists back on itself. You can walk round the corner with just a few steps but thanks to the soundproofing in audio terms it sounds like you are miles away. So two actors could appear to be yelling across a large field when in reality you're only a few steps apart.
Here's a short video showing it all in action.
Update: Since writing this post we've had the sad news of the death of Norman Painting who played Phil Archer. You can read the BBC's official obituary here.