Tuning Analysis: Casto Martínez Berriel

Verbal Description

The Casto Martínez Berriel tuning, as described by its creator, offers a highly versatile and musically rich landscape for the guitarist. The provided description suggests its suitability for "Minor chords in the first three strings (referring to the highest pitched strings), major and 7 in the four, easy those of 6." This hints at a unique interplay between chord voicings across the fretboard. It promises a "VERY GOOD" sound, with "power chords in the first three (lowest pitched strings) and cello in 2456 modified new standard tuning." This implies a deep, resonant bass foundation combined with intricate, higher-pitched melodic possibilities, potentially lending itself to compositions with a wide dynamic and tonal range, from powerful low-end riffs to soaring, almost cello-like melodies.

Technical Analysis

This tuning sets the open strings to C2 G2 D3 F4# A3 C5#, from low to high. It presents a fascinating and highly unusual arrangement of notes, creating a complex harmonic palette:

• Lowest Strings (6th, 5th, 4th): C2 G2 D3
  These three strings form a powerful C5 chord (C-G-D), providing a strong and resonant low end. The intervals are two perfect fifths stacked (C-G and G-D), making it ideal for the "power chords" mentioned in the description.
• Highest Strings (3rd, 2nd, 1st): F4# A3 C5#
  These strings outline an F# minor triad (F# A C#). What makes this particularly unique is the octave placement: the 3rd string (F4#) is a full octave higher than where an F# would typically fall if tuned down one semitone from a standard G3 string. Furthermore, the 2nd string (A3) is *lower* in pitch than the 3rd string (F4#), creating an interesting melodic inversion. The 1st string (C5#) is then again a very high pitch, forming the major third of the A string, but an octave up, completing the F# minor voicing. This widely-voiced F# minor chord spanning multiple octaves strongly supports the description of "minor chords in the first three strings."
• Overall Harmonic Character:
  The complete open tuning (C2 G2 D3 F4# A3 C5#) comprises the notes C, G, D, F#, A, C#. If C is taken as the root, the presence of D (9th), G (5th), A (6th), F# (#11th), and C# (a very high note, enharmonically D-flat, or a very high augmented 9th from C) creates a rich, complex, and potentially dissonant open chord. This unique blend suggests a foundation for advanced jazz, fusion, or experimental music, offering colors reminiscent of C Lydian (#11) but with an added C# and highly altered intervals due to the octave displacement. The phrase "cello in 2456" (G2 D3 F4# A3) points to a desire for resonant, string-quartet-like voicings across these middle strings.
• Chords Within Reach:
  The open F# minor triad on the treble strings (F4#, A3, C5#) means that F# minor chords will be readily available with minimal fretting. The strong C5 in the bass (C2, G2, D3) makes power chords easy. The description also hints at easy major, 7th, and 6th chords, which would likely emerge from specific fingerings across this unusual interval structure, allowing for creative chordal work beyond standard voicings.

How to Tune

This section details how to achieve the Casto Martínez Berriel tuning from standard EADGBe (E2-A2-D3-G3-B3-E4) tuning. Please read carefully, as some strings require significant pitch changes. Proceed with caution, as tuning strings to significantly higher pitches can dramatically increase string tension and potentially require a different string gauge to prevent breakage.

• String 6 (Low E): Tune down 4 semitones from E2 to C2. While within a safe range, tuning down a major third will result in a looser feel compared to standard.
• String 5 (A): Tune down 2 semitones from A2 to G2.
• String 4 (D): Keep as is; no change (0 semitones) from D3 to D3.
• String 3 (G): Tune down 1 semitone from G3. This adjustment typically results in F#3. However, for this tuning, the target open note is F4#. To reach F4# from a standard G3 string would be an upward adjustment of 11 semitones (nearly an entire octave). This is an extremely high pitch for a typical G string and carries a very high risk of string breakage. A much lighter gauge string is strongly advised for this string to safely reach F4#.
• String 2 (B): Tune down 2 semitones from B3 to A3.
• String 1 (High E): Tune down 3 semitones from E4. This adjustment typically results in C#4. However, for this tuning, the target open note is C5#. To reach C5# from a standard E4 string would be an upward adjustment of 9 semitones (just under an octave). This is an extremely high pitch for a typical high E string and carries a very high risk of string breakage. A much lighter gauge string is strongly advised for this string to safely reach C5#.

Important Note on String Gauges: As highlighted, strings 3 and 1 require substantial upward pitching from their standard EADGBe positions to achieve F4# and C5#. This goes far beyond typical tuning adjustments. Using string gauges specifically designed for much higher tensions or for smaller instruments (like some mandolin or ukulele strings, if adaptable) may be necessary to prevent string breakage and ensure proper intonation and playability. Always exercise extreme caution when tuning strings to such high pitches.