How to string a 7-string guitar: the extended-range strings guide

Most string launches aim at the middle of the market: another nickel .010 set for another rock player in standard tuning. This month's did not. Cleartone expanded its Power Series line with two 7-string sets, a .009 to .052 and a .010 to .056, both built on the nickel-iron blend the company uses for output and sustain, and both available now (Premier Guitar, June 3). One brand adding two extended-range options is a small story on its own. It is a better excuse to answer the question that sends more confused players to a forum than almost any other: what do you actually string a 7-string with?

The answer is simpler than the gear forums make it sound. A 7-string is not a different animal that needs a different philosophy. It is your six-string with one more string, and that one string is the entire decision.

Pull apart almost any factory 7-string set and you find a familiar six-string set with a single heavy wound string added on the bottom. Ernie Ball's 7-String Slinky Cobalt is the clearest example: it is a Regular Slinky .010 to .046, the everyman rock gauge, with a .062 added beneath it (Ernie Ball). The top six gauges are the ones countless players already know by feel.

That is good news, because it means everything you have already settled on a six-string carries straight over. Your bending feel, your pick attack, the way chords ring in the top half of the neck: all unchanged. You are not relearning the instrument. You are making one new choice, about one string, and then playing the guitar you already understand. So the rest of this guide is about that one string.

The low seventh string exists to hold a low note at a tension that still feels like a guitar string and not a rubber band. Too light and it flaps, goes sharp when you palm-mute it, and turns to mud under high gain. Too heavy and it fights your fretting hand and overpowers the rest of the set. The sweet spot depends on the note you are tuning it to.

For a standard 7-string in B (B-E-A-D-G-B-E low to high), or for Drop A where only the low string changes, a .062 on a 25.5-inch scale lands right in the pocket. It is firm enough to chug without losing pitch, and it is the gauge PRS specifies as the factory string on the Mark Holcomb SVN signature, the production 7-string most associated with modern prog-metal (PRS Guitars). Drop a half step to G# (the tuning Mark Holcomb and Periphery use on recent records) and the same .062 still works, sitting a touch looser than it does in Drop A.

Go lower than G#, or want a stiffer feel, and you step up: a .064, .068, or beyond. The principle is the only thing you need to remember. Lower target note means more gauge to keep the same tension. Our 7-string gauge guide maps the common tunings to gauges, and our B standard tuning guide covers the interval math if you are coming from a six-string.

Once the gauge is set, the wrap alloy is the second lever, and it matters more on the low string than anywhere else on the guitar. Cobalt wrap, the alloy in the Ernie Ball Slinky Cobalt line, has a higher magnetic pull than plain nickel, so it reads louder and tighter through the pickup. On the plain top strings that difference is subtle. On a heavy wound low string driving a high-gain amp, it is the difference between a defined low B and a smeared one.

That is a real part of why extended-range metal has gravitated toward cobalt over the past decade: the alloy keeps the bottom articulate when six strings are quad-tracked into a dense mix. Nickel is not wrong here. It is warmer and rounder, and if you want a little less aggression and a little more vintage body, it is the friendlier choice. Our cobalt versus nickel comparison runs the tradeoff in full. For most players chasing the modern low-tuned sound, cobalt on the bottom is the pick.

For a standard scale 7-string in B standard, Drop A, or Drop G#, the default is the Ernie Ball 7-String Slinky Cobalt. It is the .010 to .062 that ships on the PRS Holcomb SVN, so it is a known quantity for exactly this job. If you want a lighter feel up top or run a slightly higher tuning, the 7-String Regular Slinky Cobalt steps the low string down to a .056.

If you are chasing extended-range tones on a six-string instead, by tuning the whole guitar down rather than adding a string, a light-top heavy-bottom set is the move. The D'Addario NYXL1052 keeps a .010 top for normal leads and a .052 bottom that stays tight in Drop B and below, which is how a lot of players get into low tunings before they commit to a seven.

Whichever you pick, route the purchase through the set's own page so the gauge and tuning notes travel with it. Cleartone's new Power Series 7-strings are a fair option too if you want a coated set; we do not have a page on them yet, so check the brand directly for now.

Two 7-strings can take the same .062 and feel completely different, and the reason is scale length. A longer scale holds the same pitch at higher tension, so a low string that feels perfect in Drop G# on a 25.5-inch neck feels noticeably stiffer on a 26.5 or 27-inch multiscale guitar. Many modern extended-range guitars use a fanned-fret design precisely to give the lowest string more scale length, and therefore more tension, without forcing a heavier gauge.

The practical takeaway: if your low string feels like a steel cable, drop a gauge. If it feels floppy and goes sharp when you mute it, go heavier. Gauge charts are a starting point, not a verdict. The feel under your own hand on your own scale length is the real test, and a fresh set is cheap enough to experiment. If you are jumping up in gauge, our heavy-gauge install guide covers the nut and setup work a thicker low string can need.

The logic does not stop at seven. An 8-string adds a low F# below the B, and that string wants a .070 or heavier to stay defined, which is why 8-string players almost always run a long or fanned-fret scale to give it room. Tension climbs fast at the very bottom, and a too-light lowest string is the single most common reason an extended-range guitar sounds muddy rather than crushing. Our 8-string gauge guide carries the same sizing logic one string lower, and if you want to see who is actually playing these, our 7-string players guide is the rabbit hole.

The headline keeps coming back to the same place. On any extended-range guitar, the low string is where the tone lives and dies. Size it to your tuning and your scale, pick an alloy that keeps it tight, and the rest of the set is just the guitar you already know how to play.