Need a plug in battery analogue for 6v - 9v LEDs

[sdiggman]

Hello - I build miniatures that include a large number of individual LEDs in a series of phased arrays (an array for night scene - an array for action lighting - an array for set lighting - and mood arrays each lights the diorama individually)

the problem: I have to tune EACH individual LED for EACH array. I always find my self buried in battery packs (see picture) hooked up here and there to individual LEDS while having 1 or 2 of the OTHER arrays on and firing ALSO on battery packs. It gets confusing as to what is powered from where and when.

What I need to build is a plug in 6-9v (prefer 6v) power source that has three sets of connect wires

that way I can happily use a single battery pack to go from individual LED to individual LED while the other arrays are running off the power source