Class D with Common Ground?

I was not able to find a Class-D with common ground. I tried a Sure 100W for a little while but it was not quite right. I thought it would damage the Polk SDA circuit.

Having some monoblock amps I wanted to use with the SDAs, I finally put in a Triad isolation transformer in the crossover cable. Information for that is on the Polk forum. That sounds much better and the speaker circuits should be fine now.

I wouldn't hesitate to use the isolation cable with the Class-D amp.
 
@runclesid All the Sure 100W amp models I see are single supply BTL. Wouldn't expect that to work.

You want a bi-polar supply, single-ended Class-D amplifier. There's Hypex, Infineon, and Tripath to name a few different options. I'm sure there are more I'm unaware of or not thinking about.

I have some examples here with me now. Hypex UcD250LP, Infineon IRAUDAMP1, Tripath RB-TK2350.
 
So if you ran an ohm/continuity meter across the NEGATIVE speaker output posts, you'd get continuity WHILE THE AMP IS POWERED OFF?
Yes, the negative terminals are connected between it and the 0 volt mass of the symmetrical power supply.
Avoided Tpa, MA12070 chips, these are 4-channel chips almost always used in btl mode.
The MA5332MS chip may be suitable, I have 2 different amp models using this chip. The negative poles are not floating.
Reference to mass as a class AB (non-btl).