Once again, I'd have to say "I love my FourSquare™". Sometime ago I made mention about this particular technique, using two umbrellas on the FourSquare™.
During my March SSBR workshop in Denver, I photographed Andrea using this technique. The take the FourSquare™ block and I slide a 60" umbrella and a 43" umbrella into the umbrella shaft holder, there are two. As you can see from the image above, the 60" umbrella is used as a shoot through and the 43" as the bounce. The 43" has the black cover over it and as mentioned, the 60" is close to the subject in the shoot through position.
This is an incredible light, large, soft and just plan beautiful. In the image below you can see the quality of light produced from this set up. My WB in the camera was set to Daylight for the image below.
I later placed a full cut CTO over the flash head and shifted my WB to 3030*K. The resulting blue shift in the background is from the daylight coming through the window in the back of the scene. Those results can be seen in the image below.
You can view more workshop images created during various SSBR workshops HERE This link will take you to a new web site I created at SquarSpace, I hope you like it.