The ESP chip was a custom digital signal processor (DSP) chip with over 75,000 transistors. It had an instruction set that was optimized for manipulating audio data, which has typical sample rates of between 10 kHz and 50 kHz. The ESP was capable of creating a wide range of digital effects including reverb, delay, echo, flanging, chorusing, harmonizing, equalization, and distortion, and was capable of generating multiple effects simultaneously.
The ESP was a VLSI device designed in a 1.0 micrometre double-metal CMOS process. The multiplicity and flexibility of the data paths in the ESP allowed many DSP operations to be accomplished in a minimum number of microinstructions steps. Its nominal instruction cycle was 250 ns, yielding program lengths from about 64 to 160 microinstructions at typical sample rates. Because the ESP chip was fully programmable, the range of effects was unlimited.