This tuning, named "C# m6/9" and famously used in Dream Theater's "Panic Attack," is technically a Standard guitar tuning uniformly lowered by a tritone (six semitones). This means all intervals between strings are preserved, allowing familiar chord shapes and scale patterns to be played, but producing a darker, lower-pitched soundscape. The profound detuning lends itself well to heavy and progressive music, offering a thick sonic foundation.

The open strings, when strummed together, present a complex harmonic structure: A#2, D#3, G#3, C#4, F3, and A#4. While the tuning's name suggests a C# minor 6/9 chord (C# E G# A# D#), the open strings do not directly form this exact chord due to the presence of an F natural instead of an E natural. This implies the tuning name refers to specific voicings or musical contexts achievable within the song, rather than the immediate resonance of the open strings.

How to Tune:

To achieve this tuning, all strings from standard EADGBe need to be significantly lowered. Please note that dropping strings by six semitones is a considerable change (exceeding 4 semitones down). Using a heavier gauge of strings is highly recommended to maintain proper tension and intonation, and to prevent potential damage to your instrument from extremely low string tension.

• 6th String (Low E): Tune down 6 semitones to A#2.
• 5th String (A): Tune down 6 semitones to D#3.
• 4th String (D): Tune down 6 semitones to G#3.
• 3rd String (G): Tune down 6 semitones to C#4.
• 2nd String (B): Tune down 6 semitones to F3.
• 1st String (High E): Tune down 6 semitones to A#4.

• 6th String (Low E in standard): Tuned to A#2
• 5th String (A in standard): Tuned to D#3
• 4th String (D in standard): Tuned to G#3
• 3rd String (G in standard): Tuned to C#4
• 2nd String (B in standard): Tuned to F3
• 1st String (High E in standard): Tuned to A#4