Tech 21 is a New York City-based electronics company founded in 1989 by Andrew Barta, a performing musician and amp technician who spent years repairing, modifying, and customizing amplifiers before launching his own venture. Barta created Tech 21 after major manufacturers rejected his design concept — a device capable of emulating tube amplifier characteristics without requiring an actual tube amp. The result was the SansAmp Classic, an analog pedal whose name derives from the French sans ampli ("without an amp"), enabling musicians to record direct to a mixing console or perform live without a traditional guitar or bass amp.

The SansAmp concept grew into an entire product family. The SansAmp Bass Driver DI became a widely adopted tool among bass players for its ability to add tube-like warmth and grit to direct signals, and the PSA-1 and GT2 expanded coverage across guitar styles and studio applications. The Fly Rig series later condensed a full signal chain — preamp, effects, and power — into a compact form factor suited for traveling musicians. Tech 21 also builds a line of Trademark amplifiers that incorporate SansAmp circuitry alongside conventional speaker cabinets.

Distinguishing itself from competitors that shifted to digital amp modeling, Tech 21 has maintained analog circuitry throughout its product line and bills its approach as "Analog Supremacy." The company has developed artist signature units in collaboration with Geddy Lee, Richie Kotzen, Paul Landers, dUg Pinnick, and Steve Harris, producing dedicated preamp and DI units tailored to each player's tonal preferences.

Tech 21 has 116 products cataloged on Equipboard, including Bass Effects Pedals, Amp & Cabinet Simulators, and Overdrive Effects Pedals. Their gear is featured by 471 artists, with the strongest followings in Rock, Metal, and Pop. Notable users include Geddy Lee, Mike Kerr, and GUNN. Tech 21's catalog spans the full price spectrum — from entry-level options to high-end flagships.