The Mesa/Boogie 5U4GB is a classic full-wave vacuum tube rectifier, known for its rich, saggy response and vintage feel. This tube delivers that signature tube rectifier “compression” that enhances dynamics and sustain in your amp’s response—especially favored by blues and rock guitarists.

Key Features:
✔ Genuine Mesa/Boogie part – hand-tested and approved for all Mesa amps
✔ Classic sag and compression for vintage feel
✔ Designed for high plate voltage operation
✔ Rugged construction for long life
✔ Excellent in dual-rectifier or single-rectifier amp designs

Applications:
Recommended for use in amps that call for 5U4GB rectifiers, including many Mesa/Boogie models such as the Dual and Triple Rectifier series. Also compatible with many vintage and boutique amps using 5U4-based designs.

Sold Individually
This rectifier tube is sold as a single unit. No matching or burn-in is performed on rectifiers.

Why Choose Mesa Tubes?
Mesa/Boogie tubes are among the most rigorously tested and consistent on the market. Built to withstand the demands of professional use, each tube is quality-controlled to ensure reliable performance and tone.

From British Audio
British Audio is an authorized Mesa/Boogie service center and proud supplier of genuine tubes. Order your 5U4GB rectifier today and keep your amp running at peak performance.