Upgrade from Dreadnaught 11 for two channel

I am looking to go with a Two channel amp for stereo and replace my 7.1 dread II. I will use a smaller 5.1 for my HT, and that would would complete my 7.1. I am looking at the Mcintosh 406 and or the Pass Labs 250.5 amp. How do these two amps compare to each other as far as sound , bass , imaging most important warmth, and detail. Should I look into the Theta Enterpise Mono amps? . I use The tyler Linbrooks one piece speaker. Thanks for all your input Joe