Dumble musical instrument amplifiers are custom manufactured in very limited numbers by Alexander "Howard" Dumble of Los Angeles, California. Dumble amplifiers are among the most sought-after and expensive boutique amplifiers on the market; they were one of the originators of the modern boutique amp trend. The Dumble Overdrive Special was assessed as the most valuable guitar amplifier on the market, fetching on average between $70,000 and $100,000 a piece.
Dumble Amplifiers Wikipedia
Alexander "Howard" Dumble began modifying Fender tweed and blackface amplifiers in 1963 in Santa Cruz. By the late 1960s he was modifying and building high-gain amps in the way that Mesa Boogie and others did, but unlike them, Dumble was not really interested in the business of selling amplifiers in greater numbers, and became a "reclusive amp tech to the stars'".
Much of the company's PR is word of mouth, and Dumble builds his amps on special order. Carlos Santana, for instance, heard of Dumble in reference to Stevie Ray Vaughan and was lent one (it wasn't for sale); he "was hooked for life." After contacting Dumble himself, he was able to buy one, and then three more.
Dumble's German importer in the 1980s made a clone called the Kitty Hawk Standard. Since the 1980s, Dumble has covered the preamp circuitry of his amps with a thick layer of usually opaque epoxy, protecting his schematic's exact design.
In 2011, Vintage Guitar's Dave Hunter estimated there were fewer than 300 Dumble amps. Guitar Player Magazine once listed the 25 most expensive vintage amps. in the world. The Dumble Overdrive Special was #1. Used Dumble Overdrive Special amps currently sell for more than USD $70,000. There is no new price since there is no record that Alexander "Howard" Dumble has recommenced manufacturing since his retirement in the late 1990s.
Since Dumble's models were individually tailored, there aren't really distinct model lines with every amp of a certain model built with the same specifications. Nonetheless Dumble builds certain types with specific designations.
The Overdrive Special is built with 6L6 tubes, as an American-style amplifier (though he built some with EL34s like 183 which is extremely versatile and can even sound like a 6L6 at times, for a British sound it can be more aggressive also). Though originally based on a Fender blackface, it has evolved considerably. It uses 12AX7 tubes in the pre-amp section, and up to four gain stages for the lead channel.
The tonestack on Dumbles resembles that of the Fender Blackface amplifiers, though especially the midrange control is routed differently.
Dumble also made a tube-buffered external effects loop called a Dumbleator. A few Dumble amps have a Dumbleator circuit built into them. The Dumbleator has separate "Send" and "Receive" circuit for the effects; a gain control, "Bright Switch" and a return level.Eric Clapton
Stephen Bruton (had a low-watt Dumble with 4 10" speakers)
Robben Ford (bought an Overdrive Special in 1983 and had a model custom-built in 1993/4)
David Lindley (uses a Dumble cabinet)
John Mayer (Steel String Singer)
Lowell George had an early custom Dumble head he used for most of his career.
Carlos Santana (has an Overdrive Special and a Steel-String Singer besides his Mesa Boogies)
Stevie Ray Vaughan (Steel String Singer)
Henry Kaiser (1978 Dumble Overdrive Special)
Joe Bonamassa (owns 3)
Keith Urban (Overdrive Special)
Steve Kimock – 50 watt and 100 watt Dumble
Ry Cooder – Borderline Special
Ben Harper – 3 × Overdrive Specials (50w head + 2×12" Cabinet, 100/50w 1×12" Combo, 100/40w Head + matching 1×12" Cabinet)
Eric Johnson – Steel string singer #5 till it caught fire and was sold back to Steve Bruton, Eric owns an early ODS explosion era amp now currently