Tone Timeline
Robert Johnson — Tone Evolution
Robert Johnson recorded only 29 songs in 1936–37 but his influence on blues and rock guitar is incalculable. His Delta blues tone — raw, slide-driven, simultaneously playing bass lines, rhythm, and melody — was the foundation that all subsequent electric blues and rock guitar was built on.
1936–1937: San Antonio / Dallas Sessions
All Robert Johnson recordings come from two sessions: San Antonio (Nov 1936) and Dallas (June 1937). He used a Kalamazoo KG-14 (a budget Gibson) or a similar cheap acoustic — fully acoustic, no amplification. The recordings were made with a microphone in a hotel room. His tunings were primarily open G and open D for slide work; he used a glass or brass slide. The tone sounds crude by modern standards but the rhythmic and melodic sophistication is extraordinary.
Signal Chain