Standard balanced interconnects are fine.
The TAPE loop would be the appropriate place to put an equalizer, except that the signal level is probably too low for best results. Try it here first and see what happens. The reason to put it between the preamp and the power amp is to take advantage of the gain in the preamp line stage, to boost the signal level, however, if you do this you will need to attenuate the signal going into your typical audiophile power amp. If your power amp has an input level control, use it. Otherwise you might need to buy or make attenuators.
The TAPE loop would be the appropriate place to put an equalizer, except that the signal level is probably too low for best results. Try it here first and see what happens. The reason to put it between the preamp and the power amp is to take advantage of the gain in the preamp line stage, to boost the signal level, however, if you do this you will need to attenuate the signal going into your typical audiophile power amp. If your power amp has an input level control, use it. Otherwise you might need to buy or make attenuators.