Parametric Equalizer with State Variable Filter parallel

Hi everyone
I'm looking for help with a parametric equalizer schematic.
The schematic I found on www.http://sound.whsites.net is based on the urei 545 equalizer. In the urei 545 they are cascaded to each other. Is it possible to connect two of those bands parallel to each other? Lets say I would like to add 8 of those bands together parallel, what changes would I have to make to the schematic? I would need some sort of summing opamp, right?

Thanks for your help in advance!

http://www.collinsaudio.com/NetEQ.pdf

See above for a state variable EQ design with the filters in parallel.