How to control psi on more than one external wastegate

[imagine-02]

Wondering how the wastegates are controlled with these two different turbo setups:

Setup 1- Single turbo, twin scroll manifold with two wastegates.
Do you use two boost controllers?

Setup 2- Two turbos in a compound configuration with two wastegates.
Do you use two boost controllers?

I would like to use the Boost Control Solenoid (link bellow) with ecmlink, but I have a feeling you can't use the BCS when two boost controllers are needed.

ECMTuning, Inc.

 

[RadDsm]

You only need one boost controller.

You run a line from each wastegate, then Tee it into one line that goes to the boost controller.

 

[sniver]

You only need one boost controller.

You run a line from each wastegate, then Tee it into one line that goes to the boost controller.

This way would work for a single turbo, twin scroll.

For a compound setup, two are used.

Sent from my Droid

 

[imagine-02]

That's what I was thinking.
Thanks!

So the Boost Control Solenoid probably can't be used in cases where two boost controllers are needed?
Unless it's possible to T a 2nd boost controller (I'm thinking just a plain manual boost controller) off the Boost Control Solenoid. So one line would go from the Boost Control Solenoid to one of the wastegates, while the other line would go from the Boost Control Solenoid to the 2nd boost controler and then to the 2nd wastegate.

If that setup works, the 2nd boost controller would be a set number of psi different from the Boost Control Solenoid.
So say the Boost Control Solenoid is set for like 20psi and the 2nd boost controller is set for 25psi (5psi more). When the Boost Control Solenoid is turned up to 25psi, then the 2nd boost controller would automatically change to 30psi.
Does my reasoning sound right? There are probably other variables involved that I'm not taking into account.