You could try the active crossover- Adcom on the bass and the McIntosh on the highs should sound very good. Have you eliminated floor reflections? If you have hard floors placing a rug in front of the speakers can tame some of this.
I'd try the active crossover- it effectively eliminates the potential bad components in the original crossover while retaining originality. I'd bi-amp instead of tri-amping. If that ends up working you could then have new crossovers made if you wanted to. Make sure to look up at what frequency the original crossovers kick in. Crossing the midranges in at too low a frequency can roast them pretty quickly. This information should be available at the Lansing Heritage site. Good luck!
I'd try the active crossover- it effectively eliminates the potential bad components in the original crossover while retaining originality. I'd bi-amp instead of tri-amping. If that ends up working you could then have new crossovers made if you wanted to. Make sure to look up at what frequency the original crossovers kick in. Crossing the midranges in at too low a frequency can roast them pretty quickly. This information should be available at the Lansing Heritage site. Good luck!