I'm not sure the easiest way to ask this, so I'll explain what I'm trying to do. I want to build a pair of partial line arrays with 8 small full-range drivers and one subwoofer. Everything I've done before has stayed inside the safe zone (and simple zone) when it comes to impedance, so I'm lost here.

So. According to the specs of the full-ranges, they have a sensitivity of 83db and are 8 ohms each. According to the subwoofer's specs, it is 96db when the two voice coils at 8 ohms each are wired in parallel.

First question is: When it comes to impedance, does the system impedance affect the amplifier as a whole or does the way each driver is wired affect it?

Example: Say I wired four in parallel, four in parallel, (2 ohms each set), then the two sets of four in parallel with each other and in series with the subwoofer (DVC wired in parallel for 4 ohms), it would be a system impedance of 5 ohms according to an impedance calculator I hope I'm not using improperly. The amplifier I have in mind (a T-amp) would have no problem with 5 ohms, but would the sets wired into two ohms each strain the amp at certain frequencies, damaging everything involved? Or does the rest of the wiring which makes the system impedance a total of 5 ohms negate the low impedance of the other components?

I'm sorry that my question sounds so convoluted. Wasn't sure how to word that.

Also, how do you calculate the overall sensitivity of that many drivers wired in such a way? I know two identical drivers wired in parallel will yield about +6db over a single driver, but I'm not sure how to go about approximating this many. I would like them to be in the range of the subwoofer.

The whole idea behind this is to create simple but decent-sounding and quite sensitive speakers to reach higher SPLs powered by a small 20W T-amp.

I may wind up putting the subwoofer in a bandpass box if the full range array winds up being too sensitive.