Tony Iommi's guitar strings: the Black Sabbath SG rig, sourced

Documented string gauges and tunings Tony Iommi uses with Black Sabbath on his Gibson SG. La Bella custom-light .008-.032 set + tunings as low as C# standard and B standard. With citations.

Black Sabbath / Heaven & Hell / Solo · reviewed by the Change Your Strings editorial team · 2026-04-30

Tony Iommi uses La Bella custom-light gauge strings, .008-.032, on his Gibson SG signature instruments. The unusually light gauge is a direct consequence of his prosthetic fingertips: at age 17 working in a sheet-metal factory, he lost the tips of his middle and ring fingers on his fretting hand and built thimble-style prosthetics from melted-down dish-soap bottle plastic. Light strings reduce the pressure he needs to fret. Combined with deeply down-tuned guitars (C# standard, sometimes B standard or lower), the light-strings-on-low-tuning combination is the foundational tone of heavy metal as a genre.

At a glance

Role

Guitarist

Active

1968–present

Based

Birmingham, England

Genres

Affiliations

Black Sabbath (founding lead guitarist + only continuous member, 1968–2017)
Heaven & Hell (with Ronnie James Dio, 2006–2010)
Gibson (Tony Iommi SG signature line)
La Bella Strings (documented signature relationship)

Notable credits

Black Sabbath, Black Sabbath (1970)
Paranoid (1970)
Master of Reality (1971)
Vol. 4 (1972)
Sabbath Bloody Sabbath (1973)
Heaven and Hell (1980)
13 (2013, final Sabbath studio record)

Official media

Sourcing4 citations · reviewed 2026-04-30· by Change Your Strings editorial team

Who Tony Iommi is

Anthony Frank "Tony" Iommi (born February 19, 1948, Birmingham, England) is the founding guitarist and only continuous member of Black Sabbath, the Birmingham-formed band whose 1970 self-titled debut is widely cited as the first heavy metal record. The Sabbath catalog from 1970 through 13 (2013) is one of the canonical pillars of heavy metal, and Iommi's writing on the early-1970s run (Black Sabbath, Paranoid, Master of Reality, Vol. 4, Sabbath Bloody Sabbath) is the load-bearing influence on every metal sub-genre that followed.

The Heaven and Hell offshoot (Iommi + Ronnie James Dio + Geezer Butler + Vinny Appice, 2006–2010) extended the catalog after Sabbath's 1990s-era lineup turbulence; the original Sabbath lineup reunited for 13 (2013) and a final tour, with Iommi as the constant.

What he plays

La Bella Custom Light .008-.032 signature set on Gibson SG signature electrics, in tunings ranging from E standard down through Eb, C# standard, and (on later material) B standard. The light gauge is a direct adaptation to his prosthetic fingertips; combined with the low tunings, the strings sit at workable tension despite being .008 at the high E.

His primary instrument across the early Sabbath catalog was a 1964 SG Special he named Monkey. He later moved to a custom Jaydee SG (Old Boy), and on subsequent records to various Gibson production SGs and signature models. Gibson Custom Shop has issued multiple Iommi-signature SG replicas reproducing the cross-shaped fretboard inlays and his specific pickup voicing.

The signal chain into Laney amps (specifically the Laney Klipp early on, later the Laney GH100TI Tony Iommi signature head) drives the saturation. Iommi's relationship with Laney is one of the longest-running guitarist-amp partnerships in metal.

Why this fits the rig

The light .008 set is non-negotiable given his prosthetic fingertips, lighter strings need less fretting pressure, which lets him play at speed and with vibrato despite the prosthetics. The C# standard tuning lowers each string by three semitones from E standard, which on a .008 set produces a tension feel comparable to a .010 set in E standard. The combination is mechanically calibrated to his hand: light strings, low tuning, workable tension.

The tonal consequence is foundational to heavy metal. Low-tuned strings produce more harmonic content under saturation, and on light gauges the saturation is more vocal-quality and less rigid. The result is the Sabbath sound: detuned, doomy, but with melodic single-note clarity rather than chord-mush. Every metal sub-genre from doom through thrash through stoner to djent traces some piece of this technical choice back to Iommi.

If you want this rig

The La Bella Iommi Custom Light .008-.032 is the documented signature set and is in current production. For a stock-shelf alternative, any extra-light gauge (.008-.038 or similar) on a humbucker-equipped guitar tuned to C# standard approximates the configuration.

Frequently asked questions

What strings does Tony Iommi use?

La Bella signature Custom Light .008-.032, an unusually light gauge for the heavy down-tuned music he plays. The light gauge is a direct adaptation to his prosthetic fingertips, which need low fretting pressure to work; the light strings combined with deeply down-tuned guitars (C# standard, B standard) sit at workable tension and produce the doomy, low-tuned but high-clarity Sabbath signature tone.

What tuning does Iommi play in?

Across the Sabbath catalog he tuned variably: standard E on the first record, Eb standard on parts of *Paranoid* and *Master of Reality*, C# standard (each string a tritone-and-a-half below E) on *Master of Reality* (1971) and many later records, and B standard or lower on selected later material. The C# tuning is what most people associate with the canonical Sabbath sound, low, brooding, and detuned.

Why does Iommi play such light strings?

At age 17, working a final shift in a sheet-metal factory in Birmingham (the day before he was set to leave for Germany on a tour), he lost the tips of his middle and ring fingers on his fretting hand to a press machine. He built prosthetic fingertips from melted-down dish-soap bottle plastic with leather covers, which let him fret strings but required low pressure to do so. Light .008 strings reduce the fretting pressure he needs. The light-strings-on-low-tuning combination is one of the foundational technical choices that produced heavy metal as a genre.

What guitar does Iommi primarily play?

Gibson SG. His original 1964 SG Special, nicknamed 'Monkey,' was his primary instrument across the early Sabbath catalog. He later moved to other SGs (including 'Old Boy,' a Jaydee custom, and various Gibson production models). Gibson has issued multiple Custom Shop Iommi signature SGs reproducing the cross-shaped fretboard inlays and his specific pickup spec.

Is Iommi formally endorsed by La Bella?

Yes. The Custom Light .008-.032 gauge is a documented La Bella signature set produced under Iommi's name. Multi-decade brand relationship with documented signature-product status. Per FTC framing, the relationship is endorsed, not just verified-use.