Chuck, don't get too concerned with the basses when playing Irisn music. The rhythm is built into the melody so it is not important to use the basses. If your tune is in D and A then use them, otherwise don't use them at all. If you have a guitar or piano playing rhythm then the basses are not used at all. I seldom use them, and never use them at a session. We always have a guitar or two, sometimes a mandolin or bouzouki so I only play melody. Go to a few Irish sessions and you will see. Some skilled box players will occasionally tap the bass but that requires several bass buttons which you don't have. Just concentrate on the melody and everything will be fine. Have fun.

One rows played by Irish players are tuned 12TET and usually dry but some use a wet tuning.

Johnny Connolly often plays in C. He has been known to use Hohners which sound great.

Most Irish one row players use the basses. Granted not always "correct" in minors or any of the six non home keys available on a one row.

What is "12TET?"