Nakamichi stuff, need opinions

Look at my most recent post in this thread of yours:

https://www.the12volt.com/installbay/forum_posts.asp?tid=44463&PN=2&tpn=2

I guess it would (as referring to the gain) but Ravenderat, the advantage of using the PA2004 over the PA8001 is that the PA8001 is a monoblock, and you'd be runnin two sets of wires from the output block on the amp to the subs, and when your running that, that could increase impedance and distortion. (That is of course unless you wire sub to sub) I highly recommend the 2004 as it is very efficient when bridged and will give you the power you need guaranteed at 2 channels bridged. Clean, nonstop, pure power with unmistakably fantastic SQ. Nakamichi just cannot impress me anymore with their products!!!

First, the efficiency thing.  I think this is the wrong word to use here.  Do you mean, "produces more power when bridged?"  Or what?  Because a class AB amplifier, like the 4 channel, is almost always LESS efficient than the class D amplifier.

Second, the increase impedance and distortion thing.  I think you have it rather backwards.  Decreasing impedance usually increases amplifier distortion.  "An amplifier depends on a high enough impedance to prevent too much current flow through the output transistors."  See Bridgeable Amplifiers at www.bcae1.com.  When you've got more current flowing through the output transistors, like you do when you bridge, distortion generally increases. 

Ok, but wait .. the lower 2-ohm impedance is going to have the same effect as bridging the PA2004.  Distortion will also increase on the 2004.  The 8001 is probably more efficient because it is class D.  The power, 400 to each sub, will be the same. 

So, now I'm back to Ravendart's question:  why is a 4-channel amplifier better here?

I've had better sounding systems come out with the 2004 being used bridged then i have the 8001. I am telling you that by ear. It sounds better. I highly recommend the PA2004, enough said.