Arteluthe Pinnacle LS1 crossover is a modular outboard crossover, rack mount unit, one cabinet per channel. It can feed up to 3 way, low, mid and high frequencies. Phase is adjustable as well as slope, rake, tilt. It was designed to be the definitive crossover for Arteluthe high efficiency horn speakers (Cadenza family). The unit on a picture is a "dry" assembly to optimize the location of wiring (not shown).
“Also not shown is the complex ladder of fixed resistors that will be assembled next week. I doubt there is any other unit anywhere in the world, at any time in history, that is built to this extreme.” - Robert Gaboury