How to wire MTM (or 2.5) woofers if 5 channels available & are doing active XO's??

How to wire MTM (or 2.5) woofers if 5 channels available & are doing active XO's??

I gather in most cases one simply wires the woofers in parallel and feed that channel the low pass filter out--pick up 6dB in efficiency and most amps won't sweat provided the impedance doesn't get too low. What if you have the option owing to the fact I have a five channel Marantz A-V amp of driving each of the four woofers with an independent channel?

The amp is an MM-9000 that is rated at 150 per channel into 8 and perhaps 230 into 4. I say perhaps cuz it isn't rated into such and that is an employee estimate, and under power requirements, lists 450 watts. And nowhere does it say that it is spec'ed with all channels driven but is THX ultra certified whatever that means... The lit also says it has a massive power supply but those I know as I used to have a pair of back-breaking Classe M1000 monoblocks (now sadly I have just one waiting for the right sub :D) and this aint one-however it does have a pretty good sized toroidal transformer and the amp weighs 20 kg. See pic.

The woofers I will be using Usher 8948a. Haven't run impedance measurements yet but Revc = 5.6 according to Usher specs.

Anyhow, that 5.6 in parallel makes me a bit nervous and I do have an additional amp I could press into service but would rather not jf just for the sake of simplicity.

I suspect I am being too anal about all this and either way will have a couple of hundred RMS long term watts per pair available any way I slice it. But one of the objectives of this build is to have some balls and if there is a better way to do things, would just as soon do it the right way.

Finally I might build this both in 2.5 and MTM to see which I prefer--would that make a difference as in possibly isolating the 0.5 and 1.0 woofers using separate channels?

Oh, so much ignorance is being revealed by what I thought was gonna be a w/e build. Thanks god for this forum and thanks to all of you folk that keep us noobs pointed in the right direction!


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