Class D Amplifier(s) for SWARM Subwoofer System

Hi All.  I've got a SWARM subwoofer system (4 8ohm passive subs powered by two Class A/B Dayton Audio sub amps, each amp powering a pair in series).  I've recently purchased a JL Audio CR-1 crossover, which is a true swiss army knife for integrating satellites and subs.  I am considering using the settings on the CR-1 to control the subs and using Class D amplification for the subwoofers. I'm looking for recommendations and advice on questions such as:

1) Would it be better to wire two subs in series (effective impedance 4 ohms) and drive with a single Class D channel or using four separate Class D channels and powering each sub individually?

2) The passive subs themselves do not seem to be all that efficient. So how much power should I shoot for?  (Sorry, I don't have a spec)

3) Looking for suggestions on manufactured products.  I can envision anything from a four-channel design, two stereo amps.... OR if I keep the subs in series - a single stereo amp or two monoblocks.  I know that I can get a custom 4-channel amp from D-sonic (for instance) - but I'm not up on other reasonably priced options. 

4) Am I better off building my own?  It seems like hypex is as simple as buying the components and stuffing them in a case.  (But I'm pretty busy these days, so......)

BTW - I don't want to go wild spending $$$ on subwoofer amps!  Preferably I'd like to keep the expense b/t $1k and $3k.

Thanks in advance for helpful thoughts.


@audiokinesis Thanks for clearing that up about the Daytons!  I will get back when I set up the CR-1. 

Jensen ISO-MAX PC-2XR, which converts the balanced to SE signal (and +4 to -10 db conversion). I am guessing that Ralph is doing the same, but require confirmation.

@peter_s I run the same configuration and it works fine. You might test your balanced input cables for continuity and also that they are wired exactly the same. If they are out of phase you would get really low output since all that would pass would be out of phase bass information.

@atmasphere For continuity testing, you are just saying make sure that there is continuity for each of the three pin/socket pairs, correct?  If not, I have a broken cable.  I can test, but I would be surprised to have two broken cables (2 Dayton amps, 2 XLR cable runs).  How about the possibility of a different pin layout b/t my VAC preamp and the Jensen PC-2XR?  I see there are dip switches on the Jensen for grounding.....?  Thanks!

@peter_s As I mentioned before, if one of your cables is wired out of phase with the other then the sub amp will only play out of phase bass information. IOW it would sound weak. So check your interconnect cables to see if they are both wired correctly- pin 1 to pin1, pin 2 to pin 2 and pin 3 to pin 3.

I think the drivers are damaged.  I am in touch with @audiokinesis and hope to resolve promptly.