marten design alto vs miles III Vs wilson sophia?

I have not audition the Marten Alto. But I have no problem purchasing and living with the Avalon Indras, or Marten Miles III.

What are your Source (Digital/Analog), Pre and Power Amps (tube/SS)?

Avalon Indra (this should be on your list)
Miles III
Marten Alto
Wilson Sophia (not my cup of tea)

thanks, yes the avalon are on my list too , my source is digital and i will choose the amplifier after the speakers.. miles III are 91db , alto 87db not the same needs.:)

Tubes or SS for the amp?

Both Miles and Alto impedence are normally 4 ohms (and I'm sure you know this) but they drop to 3.9 to 3.8 so to get the max effort your amp should be matched correctly.

Alto for smaller rooms like my office would work great. If I move my system to spare room in my basement then I'm considering Indra and Miles III.

ceramic drivers sound more pleasant with tubes. i know one who uses antique sound lab asl hurricane monoblocks to drive the coltrane alto. 100 tube watts minimum. tubes are more live. for solid state i would recommend redwineaudio 70.2 / spectron musician monos or accuphase e-450 / gamut 150 / Pathos logos integrated. For digital Weiss DAC2 (=minerva but cheaper) or berkley alpha.

good luck