i haven’t seen or heard it tried either… however, i’m in the same boat as you and i’m about to pull the trigger on a cathedral to use specifically for vocals. i think the cathedral would be great for live vocals as it has a TONE knob and a PRE-DELAY function… which can help to keep the vocal signal clear and avoid feedback… not to mention the cathedral has awesome reverbs in its own right.

i can only tell you that you need to do one of 2 things:

1) either use run the microphone to a small format mixer and use the cathedral in the AUX SEND/RETURN of the mixer, or;

2) make sure you use an impedance matcher at the pedal end of your microphone cable to plug into the Cathedral… then make sure the outs run to either a passive (preferable) or active DI…

these two set-ups are the only way i’ve been able to incorporate vocal effects live and avoid either pissing of the soundperson or WALLS of feedback/weak signal.

No, not without a bit of bleedthrough – the Cathedral isn’t strictly stereo, it preserves a bit of a center image. If you’re okay with the bleedthrough (say, playing acoustic and singing and going into a PA system rather than an amp), you’d plug the cathedrals input to the 802’s “effects send” jack, and plug the output of the pedal to an empty channel. The volume to the cathedral is now the “effects send” knobs on your mixer. With this setup, you’ll also want to run the reverb without any dry signal – the mixer is taking care of your dry signal.