I think you could probably mimick the mandolin part on a guitar. The "chop" is just a chord
with a very short sustain. Of course then you lose the guitar part, and if you don't have another
guitar or banjo, you have no chords going on.
Something you might try, if you're going to use just a guitar, is to have the guitar strum
along, and hit an accent strum on the upbeat.
The bass usually doesn't take a break in bluegrass, although there are certainly cases
where the the bass has done so. When it does, it is usually something like even 1/8 notes
though, and not free form as in jazz. Often the bass plays a melody line if it takes a break.
Breaks are much more common for the mandolin, fiddle, guitar, and banjo.
Normally the bass just plays roots and fifths, with an occasional run. As bluegrass lacks
a percussion section, the bass pretty much takes up the part of the bass drum, and that's
where it spends much of it's time, playing on the downbeat.
It's fun stuff. See if thare are any jams going on in your area. That would be a good way
to get the feel of the style. You play more than well enough to join in on a jam.
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