I really like the Rupert Neve Designs 500 series module preamp. It's called 511. It's pretty clean without being sterile, and well – there's just something wonderful about the sound. The variable high-pass filter is very handy, and – compared to other 500-series module preamps – the price is not too bad. Especially for what you get. It's got a colouring circuit with variable settings. If you're interested in working more with different kinds of colouring of the sound, the TK-audio SP501 and the Cranborne Audio Camden 500 might also be worth looking into. For absolute "clean" there's the Weiss A1. It's pricey, and/but it's got a built in de-esser. If you want to go 19", ELBERG-ELT is a good bet. Elberg used to make the consoles for the Danish Public Broadcaster, before they went digital. He makes a stereo preamp "clean"-style called MP2, and a "mojo" one with a built in EQ called 1073. Great build quality, great sound, and relatively friendly prices. In the field I use my MKH-50 with a Sonosax R4 recorder, with very pleasing results ... and/but for sound quality / versatility / price – the Sonosax M2D2 seems like a very good way to go.