What do you look for in damping factor?

I never purchase on specs including damping factor, just sound quality. But I do know the higher the number for damping factor, the better the amp can control the low frequency drivers. A high damping factor no doubt would result in a tighter more controlled bass and would be an important spec for someone that is considering an amp to drive a subwoofer.

I'm not sure you can equate a high damping factor with large amounts of global feedback in all instances. Digital amps may be the exception in that they have a high DF of a 1000 but they don't seem to suffer in sound quality, the lack of openess or transparency. I know for sure when a conventional amp is designed with large amounts of global feedback it is usually involves a poorly executed circuit design. So it is my opinion that if your looking for an amp with a high damping factor that results in visegrip control of the low frequency drivers without sacrificing sound quality you may want to go digital.

For example I have used the McCormack DNA-1 Rev B. This amp uses no global feedback, has a low damping factor of 150 and seems to have unlimited power reserves. Because of the low damping factor the bass at times can be a bit mushy & loose depending on the preamp used but definately excels in soundstaging & sound quality, one of my all time favorites.