Hello there!
A little input on the usage of fields in my opinion/experience.
There are fields that can be combined from two different devices playing in the same time.
There are also fields that dont combine well when played together in that way.
Example for good coherence is the combo armor of light and glory with the auric energy body repair.
Example for bad coherence for me is the crystal charger together with anyone of the crystal audios from gumroad. These are better played separate.
Also when you want to cut 20 minutes you can play de-inhabiter with the remove spell/curse audio also from two smartphones in each pocket.
The point is you can try combining fields. Somethimes in dear need it seems to have a better effect (heavy attack and so on)
also good is the luck (8min) wotgether with the holy light audio.
Take care! Experiment!
Dont be religious with it! SammyG ment as i understand you shouldnt play two fields on the same device. That is pure logic. Then you make two energy streams incoherent.