Bass Gym: Making Black Sabbath’s “Iron Man” Even Heavier on Bass

It’s remarkable that “Iron Man” by Black Sabbath is now 55 years old. That infamous heavy riff still sounds fresh, monstrous, and, dare I say it, cool as hell!

The story of one of the most iconic riffs in rock and metal began in a rehearsal room when Ozzy Osbourne remarked that it sounded like a big iron man walking around. This inspired bassist Geezer Butler to craft an unforgettable bass line and lyrics with a science-fiction theme.

The song tells the story of a man who travels into the future to witness the apocalypse. He returns to warn humanity but is turned to steel by a magnetic field. Ridiculed as a harbinger of doom, he eventually loses patience and brings about the very destruction he was trying to prevent.

This song is heavy, I mean heavy, in all aspects. But is it possible to make it even heavier on bass? Let’s explore.

Download the transcription and follow along with the video below.

Power Chords and Low B String for Bass

To push the heaviness further, I added power chords and incorporated the low B string of a five-string bass. The B minor tonality of the song allows for this, and it gives the riff a deeper, more modern edge.

This arrangement is meant for bass study and experimentation. I have a deep respect for the original and encourage every bassist to learn the song in its authentic form first. My goal here was to take the best elements of the song and reimagine them in a new way for bass.

Breaking Down the Bass Arrangement

The intro is a recreation of the heavily bent notes played by the guitar. The main riff is reinforced with power chords using a combination of three and two strings, and some parts are transposed an octave lower, making use of the B string on a five-string bass. Finally, I couldn’t resist inserting a sextuplet lick in bar 26 to spice up the outro of this arrangement.