Help

My new band already has a guitar part written in tab and I would like to play the same notes only lower. I am trying to find an easier way to convert the tab to notes so that I can rewrite my parts in tab form. We use an alternate tunings and that may be why I am having troubles.

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The four thickest strings on the guitar are the same as the four strings on the bass, except the bass is one octave lower than the guitar, the two remaining strings on the guitar are B and E.
Not knowing your alternate tunings isn't much help, let's assume you are using drop D, which means the guitars low E string is tuned down to D and you've done the same with your bass that means your open E is now open D, so on the tab a number 3 on the bottom line represents F and number 5 represents G, hope this helps

Can you post the guitar tab? It'd make it easier for us to tell you how to translate it to bass.