Running Benchmark AHB2 in bridged mode and 4 Ohm Speaker

Yes, bridged amps see half the impedance of the speakers! So the sound quality may suffer. And the amp may run too hot! I don't recommend doing this! Sound quality is always better driving a higher impedance! Better to run two mono amps - one per speaker. Or one channel of each amp into one speaker.

You would need 2 AHB2 amps, one for each speaker. They can be run in bridged mono to 4 ohm speakers. There is an application note page on Benchmarks site where they did this with PCM IB2S monitors. 

@djones51 thanks but the axes of the plot they have are not readable to me. Does the impedence of the speaker ever dip below 4 ohm. This is not clear to me.

https://benchmarkmedia.com/blogs/reviews/ahb2-driving-pmc-ib2s-studio-monitors

@geek, have you considered emailing Benchmark and asking them? I have done that with other companies. I admit that chart isn't easy to read maybe they can send you a better one.