In the late 60's, when I first heard Tony Iommi with Black Sabbath playing those powerful (1 - 5) chords

it started something in me that still exists today

and that something is a relentless search for cool sounding heavy metal chords on the low strings of my guitar

Consider the following tab for normal 6 string guitar tuning

the tab shown above is a progression in G major of the 1,5,9 chord through all of the 7 modes

with the volume and gain turned way up, these are pretty heavy sounding chords

In certain keys, you can add open upper strings, and don't forget about mutating things by using the tapping hand

barring with the first finger, you can mutate these into some full string chords as in the following tab

the following tab shows an extended 6/9 version of the 1,5,9 ... easier to play on the higher frets

the following tab shows a heavy way to convert the old standard 1,5 into a triad chord

again, the unused strings can be played open in certain keys ... don't forget about barring and tapping

I've also found that the 1,4,5 ... 1,5,6 ... and 1,5,7 chords can be useful as outlined in the following 3 tabs