How to Tune to Open Slayer (CF#CF#CF#)

'Open Slayer' (C-F#-C-F#-C-F#) is the tuning Kurt Ballou of Converge used extensively on the 2001 album Jane Doe. Stacking a repeating tritone/fifth (C to F# to C) across all six strings creates a dark, dissonant open drone where one finger can slam huge, menacing chords — Ballou describes it as a heavier play on Sonic Youth's CFCFCF tuning.

Start in standard tuning (E-A-D-G-B-E) and change 6 of 6 strings:

String	Standard	Target	What to do
String 6	E2	C2	Tune down 4 semitones
String 5	A2	F#2	Tune down 3 semitones
String 4	D3	C3	Tune down a whole step
String 3	G3	F#3	Tune down a half step
String 2	B3	C4	Tune up a half step
String 1	E4	F#4	Tune up a whole step

Printable Open Slayer (CF#CF#CF#) chart (PNG / PDF)

Fun Fact

Kurt Ballou calls it 'Open Slayer' as a nod to Sonic Youth's CFCFCF tuning, dropped and reshaped for extreme metal. Some players tune the same shape a half step up to C#-G-C#-G-C#-G.

String Tension & Setup Tips

Recommended Gauge:The low C and the alternating tritone spread relax tension well below standard, so use heavier gauges (a thick low string around .056-.060) to keep the low C and F# tight for palm-muted riffing.

Gear for Open Slayer (CF#CF#CF#)

Tools that make tuning to C - F# - C - F# - C - F# easier.

D'Addario Universal Micro Headstock Tuner

A headstock tuner makes switching in and out of this tuning quick, even on stage or without a mic.

View tuner

D'Addario Pro-Winder (winder + cutter)

Retuning 6 strings means a lot of turning — a winder speeds it up and trims new strings too.

View winder

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Frequently Asked Questions

How do I tune to Open Slayer (CF#CF#CF#)?

From standard tuning (EADGBE), retune each string low to high: 6th E→C, 5th A→F#, 4th D→C, 3rd G→F#, 2nd B→C, 1st E→F#. Match each string to its exact Hz using the interactive tuner above.

What is 'Open Slayer' tuning for?

It is a drone/open tuning for dark, dissonant metal, used by Converge's Kurt Ballou on Jane Doe. Because every string is part of the same repeating C/F# tritone stack, huge chords and dissonant riffs can be moved with a single barre.

Is Open Slayer C-F#-C-F#-C-F# or C#-G-C#-G-C#-G?

The tuning Kurt Ballou coined as 'Open Slayer' is C-F#-C-F#-C-F#. The same interval shape is sometimes played a half step higher as C#-G-C#-G-C#-G, but the original Converge tuning is the lower C-F# version.