The best way to connect the DEQ2496 is in the digital domain, i.e. between a transport and a DAC utilizing the digital inputs and outputs. However, while this method provides the best sonics, it limits you to using the DEQ2496 for only one source. The second best method sonically is connecting it in the preamp's tape loop because with this method one can completely bypass the DEQ2496 if one chooses. Even though the DEQ2496 has a bypass mode, I could hear a difference between using the Behringer's bypass mode, and completely bypassing the DEQ2496 by using the preamp's tape loop.
Standard XLR ICs will work.
Standard XLR ICs will work.