The "Deep Cello Tuning" for a Cello, as its name suggests, delves into a resonant, lower register, building upon the rich heritage of cello voicings. The provided description highlights its aim to drop the standard cello tuning to A to avoid extreme tension on higher strings, which is a practical consideration for string longevity and instrument health. A key characteristic, according to the original description, is that "the bottom four strings are spaced in fifths as on a cello." While the lowest two intervals (String 6 to String 5: A1-E2 and String 5 to String 4: E2-B2) indeed form perfect fifths, the subsequent jump from String 4 (B2) to String 3 (F4#) is a significant leap of 19 semitones (an octave plus a tritone), meaning this part of the tuning deviates from a standard fifths interval. This creates a highly unusual and wide interval, dramatically altering the instrument's harmonic possibilities compared to a traditional cello. The subsequent intervals from String 3 (F4#) to String 2 (B3) — a descending perfect fifth — and String 2 (B3) to String 1 (E4) — a perfect fourth — further contribute to a unique, non-linear string progression, setting it apart from typical cello or guitar tunings. This tuning, therefore, offers a blend of deep, resonant low notes and bright, perhaps dissonant or arpeggiated high registers.

Technical Analysis & Open Chords

Given the distinct and often wide intervals, particularly the large gap between the 4th (B2) and 3rd (F4#) strings, this tuning is less suited for conventional strummed chords and more for melodic lines, arpeggios, and drones. The lowest three strings (A1, E2, B2) create a powerful open voicing resembling an A5 power chord with an added 9th (B), providing a strong, resonant bass foundation. The overall tuning A1-E2-B2-F4#-B3-E4 doesn't immediately lend itself to simple open triads or seventh chords due to the varied and unusual intervals in the middle. The F4# note introduces a bright, sharp quality that contrasts sharply with the lower, open fifths. The upper strings (F4#, B3, E4) form an interesting cluster, allowing for voicings like a Bsus4 chord (B-E) or an F# minor triad with an open B (F#-B-E). Performers might explore open string drone possibilities, using the deep A-E-B as a foundation for modal or modern compositions. The significant jump between the middle strings allows for contrasting sonic textures, moving from deep resonance to much higher, brighter tones.

How to Tune

• String 6 (Lowest String), tuned to A1: To achieve A1, tune down 7 semitones from its implied standard pitch of E2.
• String 5, tuned to E2: To achieve E2, tune down 5 semitones from its implied standard pitch of A2.
• String 4, tuned to B2: To achieve B2, tune down 3 semitones from its implied standard pitch of D3.
• String 3, tuned to F4#: To achieve F4#, tune down 1 semitone from its implied standard pitch of G4.
• String 2, tuned to B3: Keep as is; no change from its standard pitch of B3.
• String 1 (Highest String), tuned to E4: Keep as is; no change from its standard pitch of E4.

Important Note: When tuning strings significantly (more than 4 semitones up or down), it is highly recommended to consider using a different string gauge to ensure optimal tension, tone, and to prevent string breakage or damage to your instrument. For this tuning, String 6 (-7 semitones) and String 5 (-5 semitones) require substantial downward adjustments, making string gauge consideration particularly important for safety and playability.

String 6: A1 (Lowest String)

String 5: E2

String 4: B2

String 3: F4#

String 2: B3

String 1: E4 (Highest String)