+1 on slightly favor the neck (bass) PU volume.
Since the inherent Alembic tone is so clear and the highs really ring out, you don't need to crank a ton of treble on the instrument to get a nice articulate slap tone.
It opened a whole new world for me because I can actually dial out some high end and keep the basic tone punchy and meaty and still have enough high-end on tap for slap.
Previously on other instruments, I'd have to add highs, which thinned out the tone while also creating that other undesirable byproduct - pops, clacks and and string noise.
Of course, you may need to fine-tune your settings to accommodate your technique, but these basic guidelines should get you going in the right direction.