best preamp for old Mark Levinson 29

I have heard that with an ML-38 in to maggies, sounded awesome.

I have a 380S which was upgraded from the 38S. There is a huge difference between the 380S and 38S, particularly in terms of transparancy. However, for the 29, unless you really need the ergonomics of the 380s I would recommend the 26 series. It probably sounds as good (some think it was the best pre Madrigal ever made--not counting the 32)--and it will be a lot cheaper.