Sick of letting those pecky violins, or worse yet a sax, outpower your poor little Irish flute? Let's power up!
Caveat: This is definitely a first draft version of the setup, but it does seem to work ok. I play a keyless flute. I'm not sure what might need to be tweaked for a flute with keys. I've tried this on D and C flutes, as well as a D fife.
Ingredients
Connect the microphone to the preamp and the preamp to the extension cable. These components are all 1/8" (3.5mm), so you need the headphone adaptor to convert this to the 1/4" plug that the amplifier expects. The preamp (battery powered) is critical for powering the microphone and boosting its signal to something the amplifier can handle. It's a bit pricey but I've used it on a number of occasions to get good sound out of dodgy computer microphone systems.
Now, attach the microphone to the flute. One good location seems to be at the foot end, pointing up along the line of finger holes. Clipping the mic to one's clothing might work. Attaching it near the embouchure is not as good, because it picks up a lot of breath sounds. I lost the windscreen that came with this microphone, so I don't know if it would reduce this problem.
To attach the microphone to the flute, wrap a protective strip of leather around the foot to protect the wood, then wind a rubber band around the leatherh (not very tight). Tuck the microphone under a couple loops of the rubber band. Adjust so it's not in the way of wherever you like to park your little finger. A big advantage of this microphone is that it's small, so it doesn't get in the way of your fingers or weigh down the end of the flute. Caveat: for a fife, you may need to adjust where you perch your right little finger.
Put the preamp on your lap or hook it to your pants. The 3' microphone cable is a nice length for reaching up to the flute and it isn't heavy enough to be obtrusive. (This mic is also available with longer cables.) The preamp separates the flute and microphone from the longer extension cable, preventing the extension cable from pulling on the flute.
To avoid feedback, position the amplifier so it is well separated from the flute and/or pointed away from the flute and/or behind you so your body is between the two.
Finally, remove the rubber band and leather stuff when you put the flute away. It might or might not damage the wood if you leave it on for extended periods and you don't want to find out the hard way.