Spirocore S39 Bass E String: Medium

The Spirocore S39 Bass E String: Medium is a premium replacement string for double bass players who want a strong, focused low end with the quick response and long-lasting performance that have made Spirocore a longtime standard. As part of Thomastik-Infeld's Spirocore Orchestra line, the S39 is the medium-tension E string for 4/4 double bass, built for players who need clarity, projection, and stability from the lowest string on the instrument.

Built with Thomastik's Spiralcore construction and chrome outer material, the S39 is designed to deliver the lively, flexible feel bassists expect from the Spirocore family. The official product listing also specifies an aluminum ball and crimp ball end, helping confirm compatibility with standard tailpiece setups. For advancing students, serious amateurs, and professional bassists looking for a full-size upright bass E string with dependable response under both the bow and the hand, the S39 remains one of the core choices in the Spirocore Orchestra lineup. This player-use description is an inference based on the published construction and product positioning.

Features & Specifications

• Instrument Fit: Designed for 4/4 double bass.
• String: E string, listed as E1 Mi1 IV.
• Tension: Medium tension.
• Manufacturer Model: Thomastik-Infeld S39.
• Core Material: Spiralcore construction.
• Winding Material: Chrome outer material.
• Ball Material: Aluminum ball.
• Tailpiece End: Crimp ball end.
• Tension Value: 34 kg / 74.96 lb.
• Line: Part of the Spirocore Orchestra double bass series.
• Craftsmanship: Thomastik-Infeld describes its strings as handmade in Vienna.
• Use Case: A strong choice for players seeking a premium orchestral bass E string with a responsive, durable feel. This is an inference based on the published construction and line positioning.