If you routinely play into a microphone, this example should convince you to do the sound check with the softest whistle in your inventory (in my case, an O’Riordan low E). In this video the difference is dramatic. I’m plenty loud in “Sally” (I’m about three inches from the mic with the high D), but in “Frank’s,” I’m about a nanometer away from the mic, and can only clearly be heard on the high notes. AAaaaargh… I’ve begged for months to do the sound check with tunes on which I play the E. But aside from that caused by a consistent diet of pork chops and beer, I carry no weight (alas).
That’s your punishment for chickening out on playing an A tune on your D whistle. 
Et tu, Bruté? ( 
Thanks, John!)
Yeah, I know… At break-neck speeds, though, the G# is a little cleaner on the E using XXX Xoo rather than half-holing on the D. Of course I could skip the maj. 7th altogether. Indeed, in that set, I should continue on the D. Thanks! Done!
(That doesn’t preclude my need to sound-check with the E as there are several tunes I use it on.)
When you do that little 3-note accent
instead of playing along the first time
through (which I like very much), you
can be heard just fine. Any idea what
you were doing different there than
when you played along the second
time through?
The 3 notes in the first bar of the first B part are an octave higher, essentially:
K:A
c’z2b z2az|effe cABc|dfff ecA2|faec Befg|
Yeah, when I listen to it again, the first measure
of the B part when you’re playing along is more
present. Especially the higher variation the last
time through.
I think that if you had enough gain to compete with the fiddle (which overpowered nearly every note you played), you would have been in feedback hell when playing the high whistle or even the high register on the low one. That’s why I set my gain for my low whistles in transverse position. You get less risk of feedback. You just back off for high whistles instead of cramming in for low ones. You can always play quieter without feedback. It’s tryng to double your volume that gets you in trouble.
Great stuff, Bo! You’ve got a new fan (on MySpace anyways)…
I tend to set my PA volume on a low D, playing very close, then I gradually back off as I get up the scale… up to a foot away (or at least off-axis) in the high octave on the high D.