Overview
This King 4BF tenor trombone from the 1970s, serial number 693976, is a classic professional .547-bore instrument with an F-attachment. It was offered by The Brass Exchange in fully serviced, player-ready condition.
The instrument features an 8.5-inch yellow brass bell, traditional-wrap rotor valve and nickel silver handslide with a yellow brass end crook. Its components and lacquer were original, with no history of major damage or repair.
Before being offered for sale, the trombone received a complete professional shop service, including chemical cleaning, rotor service and handslide optimization. The resulting instrument was clean, responsive and ready for immediate use.
Player Perspective
The King 4BF is particularly well suited for a commercial player who normally performs on a King 2B or 3B but needs a dependable large-bore tenor for occasional orchestral, concert band or doubling work.
A recognizable design character runs throughout the King trombone line. Players moving from a smaller King model may find the 4BF’s articulation, feedback and overall response more familiar than those of some competing large-bore designs.
This model is also a practical option for an advancing musician purchasing a first professional-level large-bore trombone. It provides the size and capability required for concert band and orchestral settings without feeling excessively difficult to manage.
This example also includes a nickel silver index-finger support ring integrated into the mouthpiece receiver. This subtle ergonomic feature provides additional comfort and control, particularly for musicians with smaller hands or those who prefer a more secure and relaxed grip.
Condition Summary
- Complete professional shop service performed
- Chemically cleaned
- Rotor serviced and operating properly
- Handslide optimized, aligned and moving smoothly
- Clean inner slide tubes with no plating problems
- Dent-free when offered for sale
- Original lacquer and components throughout
- No history of major damage or repair
The instrument was inspected and play-tested at The Brass Exchange and performed as intended.
What Was Included
- Original King case in good condition
- No mouthpiece
Questions Players Often Ask
Who is the King 4BF best suited for?
It is a strong choice for players who normally use smaller-bore King trombones but need a large-bore tenor for expanded repertoire. It can also serve an advancing player moving into a first professional-level symphonic trombone.
How does a King 4BF compare with a Conn 88H or Bach 42B?
All three models occupy the traditional professional large-bore tenor category, with .547 bores and approximately 8.5-inch bells. The Conn 88H is commonly associated with a rose brass bell, while the Bach 42 has been produced with yellow and gold brass bell options.
The King 4BF approaches the same category from a different design lineage. It retains more of the characteristic King feel, which players coming from a 2B or 3B may find familiar and easier to transition into. The best choice ultimately depends upon which design and response feel most natural to the individual player.
Availability
This King 4BF tenor trombone has been sold. This page remains available as part of The Brass Exchange reference archive.