Bass amp for a tri-amped system?

IME, you can definitely optimize certain aspects with various amps that address a particular range better.

But in the long run, after you've gotten used to the sonic effects of that combo, the more cohesive and musically compelling sound from matching amps outweighs the "audio excellence" of disparate amps with disparate dynamics, tone, phase response, etc.

So the job of discovering the best amp that will work at all frequencies is much more difficult.

About the only time I've had luck mixing & matching was with subs working from 40 Hz or lower.

YMMV...

Please forgive me, but I don't understand the "disparate" problem if the active crossover prevents frequency overlap. and once again, it is the lowest of frequencies I'm trying to address probably below 40 Hz. Getting "used to it" doesn't explain the evaluations performed by qualified audiophile visitors. Once again, I think I understand the reality of mixing amps, it's well documented. however, I believe in this case, it minimally applies.

I've heard setups both ways. I think with a passive crossover, using the same amps makes sense and in my experience sounds better. With an active crossover it will sort of blend the two or three amps sound's together so there may be less sonic differences in the end and should sound like one voice. I would make sure to use all the same cabling either way I think. Your system looks and I'll bet sounds awesome. My speakers, Legacy Helix, are quadruple amped using a Xilica digital crossover and are supplied with about 3,600 watts per channel. Talk about headroom!
You might want to check out my system as well.

Thanks Sgr, I appreciate your perspective, especially after seeing your system!
Cabling to the amps are all Stealth Metacarbons with Stealth Indra upstream so I think I'm following your advice.

I asked this same question recently and didn't get a useful response -- maybe because I didn't provide enough info. What is the low frequency driver's nominal impedance and how about efficiency? I have a pair of subs with a 2.5 ohm nominal impedence that are over 90 dB per watt efficient. I don't need a lot of watts; I need current drive into low ohms. I'm looking at a Magtech or possibly a Coda. Plinius attracted my attention but not sure how it'd fare at sub- 4 ohms. My system is tri-amped, I use different amps and I have no problem with coherency but I have heard this argument. It certainly shouldn't be much of an issue with an active XO @ a low crossover point and a steep slope.