Is this one of the ones with the cable that runs in between the two speakers? You need to be very careful as they require a common ground so that means no bridges amps and monoblocks are not a good idea. I used to have a pair of the SDA-1s and tried driving them with an NAM intergrated which pooped out in the current department and shut down. I would say tubes are a BAD idea and you probably want to look at something with at least 100 watts and can throw a lot of current. Probably the opposite direction of how you would like to go.
