Dumble, a renowned guitar amplifier manufacturer based in Los Angeles, California, was established by Alexander "Howard" Dumble (June 1, 1944 – January 16, 2022). The brand gained fame for its custom, handcrafted amplifiers that were personally built by Dumble himself, contributing to their exclusivity and high market value. The amplifiers are considered the most expensive boutique options on the used market, with prices soaring due to their rarity and quality.

Dumble's amplifiers, known as the Dumble Overdrive Special (ODS), are highly sought after and have fetched prices ranging from $70,000 to $150,000 for used models, often exceeding these figures. Dumble built only a small number of amplifiers annually, typically two to three units, primarily catering to celebrity musicians and recording studios. He intentionally priced the amps similarly to the used market to discourage resale.

Dumble's journey began with modifying Fender tweed and blackface amplifiers in 1963. By the late 1970s, he specialized in creating high-gain amplifiers, focusing on delivering the best possible sound rather than mass production. His amps gained a reputation for exceptional tone and durability, becoming highly sought after by professional musicians.

The Dumble brand's reputation was largely built through word of mouth, with limited advertising and interviews. Renowned guitarists like Carlos Santana and Robben Ford discovered the amplifiers through recommendations and were drawn to their unique sound qualities. Dumble's amplifiers featured distinctive characteristics, such as thick epoxy covering the preamp circuitry to protect his designs, and an emphasis on harmonic richness and transparent tones.

Dumble offered two main amplifier models: the Overdrive Special and the Steel String Singer. The Overdrive Special was a two-channel amp with cascading overdrive channels, while the Steel String Singer was a clean, single-channel amplifier with reverb. These models exhibited variations in sound and features across serial numbers.

Dumble's amplifiers were known for their exceptional quality and dynamic response. The Overdrive Special was particularly acclaimed for its harmonically rich overdrive channel and transparent clean channel. The Steel String Singer was characterized by its "clean feedback" effect, and its users included renowned guitarists like Stevie Ray Vaughan, Eric Johnson, and John Mayer.

Dumble's impact extended beyond his lifetime, with his amplifiers continuing to be valued by musicians and collectors alike. His innovative designs, dedication to quality, and the legendary tone of his amplifiers solidified his legacy in the world of guitar amplification.