Custom Tones, LLC is a boutique guitar effects company based in the USA, founded by Rob Hall, an electrical engineer with a long career in aerospace electronics and decades of experience building amps and pedals. The company operates under the Ethos Guitar FX name and focuses on small-batch, made-to-order pedals that Hall assembles himself.

The brand is best known for the Ethos Overdrive, released in 2007, a preamp-style pedal designed to capture the feel and response of the rare Dumble Overdrive Special amplifiers. The Ethos line has grown to include the full-format Ethos 2-Channel Overdrive + Boost, the smaller Ethos Clean II single-channel preamp, and the Ethos Clean-Fusion II two-channel preamp, along with variant mods such as the TLE (Tighter Low End) and HRM post-EQ options. The lineup also covers tremolo effects like the Ethos 60's Harmonic Bias Trem and Dual 60's Harmonic Bias Trem, plus the CFD F-Boost.

Custom Tones occupies a niche among D-style and Dumble-inspired pedal builders, with a reputation for hand-built workmanship and circuits aimed at players seeking clean headroom, dynamic overdrive, and amp-like preamp tones suited to blues, jazz fusion, and rock contexts.

Custom Tones LLC has 5 products cataloged on Equipboard, including Guitar Preamp Pedals, Amp & Cabinet Simulators, and Tremolo Effects Pedals. Their gear is featured by 1 artist, with the strongest followings in Blues and Jazz. Notable users include Tim Lerch.