✦ Historical Perspective
The King 4B straight tenor trombone represents one of the classic large-bore designs in the King professional lineup. Built during the mid-1970s, this example (serial number 629397) reflects the company’s continued focus on producing versatile professional instruments that could bridge jazz, commercial, and concert ensemble playing.
The 4B is often considered the larger sibling of the King 3B, maintaining the focused tonal core associated with the King “Sweet Tone” concept while expanding the sound with greater breadth and projection. Where the 3B excels in small-bore agility, the 4B introduces the fuller presence of a .547 large-bore slide, giving players additional depth and weight in ensemble settings.
This particular instrument is the straight-tenor version of the King 4B, meaning it shares the same bell and slide design as the trigger model but omits the valve section. Many players enjoy this configuration for its open response and lighter overall feel, which can make articulation and phrasing feel especially natural.
The horn was professionally refinished with new lacquer before arriving at The Brass Exchange, giving it a clean and attractive appearance while preserving the instrument’s underlying structure and playability.
Large-bore straight tenors like this have long been appreciated by players who regularly perform on .547 orchestral tenors or bass trombone but want the immediacy and airflow of a straight instrument. Throughout jazz history, artists such as Curtis Fuller and Slide Hampton demonstrated how a large-bore straight tenor could deliver both power and flexibility in ensemble and solo contexts.
Player Perspective
In the hands, this King 4B feels balanced, responsive, and comfortable.
The slide moves smoothly with excellent alignment and no drag, making it easy to manage both technical passages and broad phrasing. The tone retains the familiar King clarity and centered projection, while the larger bore allows the sound to open up with added warmth and depth.
For players who already perform on large-bore instruments, the transition to a straight 4B can feel especially natural. The size, balance, and airflow provide a familiar response while giving the player a direct, lively feel without the resistance of a valve section.
This type of instrument works well for:
• Jazz and big-band section playing
• Commercial and studio work
• Players moving between bass trombone and tenor
• Musicians who prefer a large-bore straight tenor feel
Specifications
• Model: King 4B Straight Tenor Trombone
• Serial Number: 629397
• Era: Mid-1970s
• Bell: 8.5″ yellow brass
• Bore: .547″ handslide
• Slide: Nickel silver with yellow brass end crook
• Mouthpiece: Large-shank starter mouthpiece included
• Case: Included
This is the straight-tenor version of the King 4B, sharing the same core design as the F-attachment model but without the valve section.
Questions Trombone Players Often Ask
How does the King 4B compare to a King 3B?
The 4B is essentially the larger-bore counterpart to the 3B. It maintains the focused King tonal center while offering greater warmth, projection, and overall breadth of sound.
Who typically prefers a large-bore straight tenor?
Players who already perform on .547 tenor trombones or bass trombone often find large-bore straight tenors especially comfortable. They are popular in jazz, commercial, and ensemble playing where players want the openness of a straight horn without the resistance of a valve section.
What is included with the instrument?
A large-shank starter mouthpiece and case are included. The instrument was cleaned, inspected, and prepared before sale.
🔧 Availability & Archive Status
This King 4B Straight Tenor Trombone has been sold and is now preserved in The Brass Exchange Archive of Sold instruments as a reference for players researching vintage King trombones.
If you enjoy exploring the history of King trombones, you can browse additional examples here:
👉 View the King Archive of Sold instruments:
Inventory changes frequently, so similar instruments may appear again.
👉 Browse current trombone listings here:
https://thebrass-exchange.com/trombones 🔎
📣 Downsizing a Collection or Selling a Brass Instrument?
Many of the instruments we handle come from retired musicians, collectors, or families managing professional instrument estates. We regularly assist players who are downsizing personal collections or looking for a trusted shop to help sell professional brass instruments.
If you are considering selling a King, Bach, Conn, Shires, Yamaha, Edwards, or other professional instrument, we can help evaluate options including:
• Outright purchase
• Consignment sales
• Trade-in toward another instrument
• Estate instrument evaluations
✍️ Start the conversation here:
https://www.thebrass-exchange.com/contact-us
🛡️ Why Players Trust The Brass Exchange
Every instrument is inspected and evaluated in-house before listing. Slide alignment, mechanical condition, and real playability are confirmed so each instrument arrives ready for rehearsal, recording, or performance. Since 2010, The Brass Exchange has specialized in professional brass instruments with accurate representation and expert guidance for both buyers and sellers.
