Not sure what the output level of the mic out line is but I would assume it would be a regular line out. (never assume).
Most likely you could run that into a second amp with effects. Most preferable an amp with an effects loop. Would give you decent sound and a place to start your verb quest.
I've gotten some great results lately by just running a signal tap directly from a speaker(dry) into a second amp(wet). This is the same as using a second speaker output from the amp as well. Since the level for the wet is much reduced for the album sound, you can just have a small amp for that. Im just using a modified Epiphone valve junior into a Celest V30 1/12 for the wet and a 4/12 for the dry. You dont need a 4/12. A single 12 will do.
With a digital plate reverb and some delay, its pretty tight. The trick is the mix of the dry and wet from 2 separate speaker sources. Amps with effects loops really can not accomplish that sound because of the conflicting texture of the sounds will muddy. They still come out of the same source speaker. IMO.
Welcome brother.....
Warning: don't feed "Dirtycooter" or "Leadguy".
