The Fatboy, despite its unusual name, lives up to its moniker in terms of both size and sound. It's significantly larger than typical clarinet barrels, boasting a robust, resonant tone. Yet, its unique design ensures that this big sound remains warm and dark, taming any brightness that might otherwise creep into your playing (especially useful for R13 Bb or A clarinets). Remarkably, this barrel is compatible with both Bb and A clarinets, making it a versatile addition to your instrument collection.