If you are not dead set on Mac, then there will be lots of options. I would suspect that the tube amp requirement is for better (as respects those qualities that tube fans like) 2 channel audio playback? In that case, consider a 2 chnnl tube amp for the mains and a cheap multi-chnl SS amp for the rest of the spkrs. For movies, there is no need or value to tube amps, IMHO. I don't know the sensitivity or impedance range of your spkrs, but that info would probably help determine good amp matches. While Mac is good at pre/pros, these are not tube designs (afaik), and I think there are far better and more cost effective pre/pro solutions than Mac. Many, many easily within your budget (especially used). Will post some actual equipment ideas later or tomorrow. Good luck.