I think the "old" 7B ST can give an answer to this question. The 7B ST had a switch where you could bridge it either in parallel or in serial mode. One gave you more power on higher impedances, the other made the amp more powerful in terms of current delivery.
James, correct me if I'm wrong, but I think the 7B SST has been fixed at one of those bridging options and it has been the mode that delivers more current at lower impedances, i.e. difficult loads.
Cheers!
Markus
The switch is no longer is available so you have to order either in Parallel or Series mode.
james
