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In addition to Olin's answer:

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 > and I'm particularly interested in jfets and mosfets.

If you decide to go down the FET route the dilemma between J and MOS gets down to home much you are willing to pay in order to have less noise in the next stage.

MOSFET's have the conducting channel under the gate oxide and like nothing in this world the channel is not 100% "clean" - it has defects. These defects reduce the mobility of electrons which flow through it which as a result has higher 1/f noise. JFET's add a depletion layer between the gate and the conducting layer so they have less 1/f noise. They are quite often used as preamplifiers in the audio industry.