Step Up & Save: Rent or Buy Today 

XO 1240L-T Professional Bass Trombone - Clear Lacquer

Bass Trombone with 9.5" Yellow Brass Bell, Open Wrap, Dual Independent Rotors, Thru-Flo Valves, 0.571" Bore, 3 Interchangeable Leadpipes, Yellow Brass Outer Slide, and Chrome Inner Slide - Clear Lacquer
Share
Item ID: XO1240LT
XO 1240L-T Professional Bass Trombone - Clear Lacquer
Price:$7,864 and 00 cents
Special Financing - Ends May 17, 2026. $164/month with 48 month financing*

New! Band and orchestra instrument rentals.
We Can Get It!

While this isn't an item we normally stock, we can still get it to you as fast as possible due to our great relationship with XO. Go ahead and place your order and we'll follow up shortly to let you know when to expect it. Estimated May 2026.

Add to Cart
Sales engineer photo
Ask An Expert

Our expertly trained Sales Engineers are ready to help!

What is a Sales Engineer?
XO 1240L-T Professional Bass Trombone - Clear Lacquer
We Can Get It!
Price:$7,864 and 00 cents
Add to Cart
Add to list
Skip to Description
Most Popular Accessories & Related Items
Back to navigation

This article was Written By

Our Product Research Team

Get to know them!

Flexibility for Any Ensemble

Built for the professional player, the XO 1240L-T bass trombone offers the perfect amalgamation of traditional tone and contemporary playability. The 1240L-T is equipped with both F and Gb attachments and dual independent rotors, which give you a fully chromatic range of low tones. On top of that, the 1240L-T comes equipped with XO’s Thru-Flo valve, which effectively eliminates resistance as you blow. Each rotor has gold-plated channels for easy maintenance, and you’ll love the rich, colorful sound of the 9.5-inch yellow brass bell. Plus, the 0.571-inch bore lets you push plenty of air for powerful projection. What’s more, this trombone includes three interchangeable leadpipes that allow the player to customize the feel and response of the horn. Sweetwater Sales Engineers highly recommend the XO 1240L-T bass trombone if you’re looking for a horn that can hold its own in any ensemble.

Thru-Flo axial flow valve for a truly “open” sound

The trombone’s unmistakable sound is a direct result of arrow-straight airflow and cylindrical tubing. And as much as a trombone’s valve opens the door for extra-low playing, it can also color your tone in undesirable ways. That’s where the Thru-Flo valve design comes in. XO’s take on the well-loved axial flow valve, the Thru-Flo valve, eliminates the sharp bends found in traditional rotor valves for straighter airflow and less resistance than ever before. Trombone players at Sweetwater report that Thru-Flo valves provide a free-blowing feel that you have to experience to believe.

Powerful yellow brass bell

The XO 1240L-T ships with a highly responsive yellow brass bell. Measuring an expansive 9.5 inches, this bell delivers a rich, vibrant sound that rings clearly across all registers. The yellow brass gives this bass trombone a punchy, direct sound, making it ideal for bombastic playing in large symphonies, wind ensembles, and jazz big bands. You’ll appreciate the 1240L-T’s authoritative projection at loud dynamics and its nuanced response for quieter articulations.

Dual independent rotor valves

A bass trombone’s attachments are integral to the horn’s sound. XO knows this, which is why the company pulled out all the stops to produce responsive attachments to enhance your low end. This professional bass trombone comes equipped with dual independent F and Gb attachments, giving you a chromatic range of low tones that standard dependent systems cannot match. And since each rotor is independent, you get greater playing flexibility for technical passages. What’s more, XO includes gold-plated rotary channels to ensure upkeep is a breeze.

Customize your playing experience with interchangeable leadpipes

XO is committed to delivering the best possible playing experience with each of its instruments. A trombone should feel like a perfectly natural extension of yourself, and breath resistance plays a major role in achieving that “perfect” feeling. The 1240L-T comes with three interchangeable leadpipes, so you can customize the horn to fit your unique tonal needs. In addition, XO included a removable gold-plated counterweight to further customize the feel of your 1240L-T trombone.

XO brass meets the mark for today’s top players

The XO brand was born out of the vision of Koichi Haido, Chief Instrument Technician at the Global Corporation in Japan. Designed for today’s top players, XO brass instruments leverage the industry’s leading performance options. The company’s specially tailored features enhance the performer’s experience with incredible sound, clarity, and resonance, at all volumes, in all venues, and under any performance demand you may encounter. Each XO instrument is inspected for quality throughout the manufacturing process, ensuring it can endure bumps and bruises as easily as navigating challenging technical passages. Sweetwater strives to meet the demands of our professional-level customers, and XO instruments meet the mark.

XO 1240L-T Features:

  • Top-notch professional bass trombone
  • Dual independent rotor valves allow for a greater range of low tones
  • Open-wrap configuration lessens resistance
  • Thru-Flo axial flow valves effectively eliminate wind resistance
  • 0.571-in. bore delivers a free-blowing feel and centered timbre
  • 9.5-in., 2-piece yellow brass bell offers up a warm, rich tone
  • Expertly fit yellow brass outer slide responds to your slightest touch
  • Interchangeable leadpipes allow you to customize the horn’s response
  • Gold-plated rotary channel makes upkeep a breeze
  • Lacquer finish adds a warm quality to the tone
  • Includes Session-style case and mouthpiece

Warranty Info

Sweetwater's FREE 2-Year Total Confidence Coverage Warranty

Extra peace of mind at no extra cost.

  • Save money with FREE parts and labor
  • Get back to making music with the industry's fastest turnaround time
  • Fix it the first time with our award-winning, factory-certified Service Department
Learn More about Total Confidence Coverage
Back to navigation

Tech Specs

  • Key: Bb with F/Gb/D Attachment
  • Type: Bass
  • Wrap: Open
  • Valve: Dual Independent Thru-flo
  • Level: Professional
  • Finish: Clear Lacquer
  • Bore: 0.571", Large
  • Bell: 9.5"
  • Bell Material: Yellow Brass
  • Inner Slide: Chrome-plated
  • Outer Slide: Yellow Brass, Nickel Silver Crook
  • Leadpipe: 3 x Interchangeable
  • Leadpipe Material: Yellow Brass (260mm, 220mm), Sterling Silver (220mm)
  • Mouthpiece: Jupiter 5G
  • Receiver: Large Shank
  • Additional Features: Gold-plated Channel
  • Case/Bag: Hardshell Case
  • Manufacturer Part Number: 1240L-T

What Makes Our Sales Engineers Great?

Sweetwater Sales Engineers are a world-class team of experts dedicated to you. Hand selected from across the globe, each brings a wealth of experience and expertise in the world of music gear to provide you with unparalleled service completely free of charge. Friendly relationships, real trust, and the right gear are only a call or a click away!

Back to navigation

Customer Reviews

Be the first to review this product.
Write your review
See also: XO, XO Trombones