help please!

[Rob Adler <radlerr@gmail.com>]

here's my prob: i've gotten up to snuff on the looping capabilities,
but there's one thing i could do with the jam man that i haven't been
able to figure out how to do with the echoplex: record and then
trigger a sample and only have it play back once, and only when i step
on the pedal. what i do is play a note or phrase, sample it, and then
play it back while i play something else over the top of it. need to
have the ability of triggering it manually, as it has to be in the
rhythm of the rest of the band.