Error Instruments is an experimental electronic music instrument maker based in Amsterdam, Netherlands, founded by artist and industrial designer Paul Tas. The brand specializes in handmade Eurorack modules and standalone sound devices built in small runs — often capped at 20 to 50 units — using unusual components like vacuum tubes, tropical capacitors, vintage chips from the 1950s–70s, and vactrols. The name traces back to Tas's childhood nickname, drawn from the "syntax error" messages on Commodore 64 computers.

The catalog leans toward the experimental and sculptural side of modular synthesis, treating instruments as sound art objects. Products include the Brinta granular sampler, the Loopman experimental tape recorder module, the Spanky (also known as Transyndrum) drum synthesizer with touch distortion and gate sequencing, the Tele Blender, the Liquid Glitcher oscillator, the Passive Operator, Imaginary Friend synth voice, White Rabbit, and Cloudbusting, a fully modular self-contained Eurorack system. Units are hand-assembled through-hole rather than SMD.

Tas began producing Eurorack modules in 2018 after conversations with Dieter Doepfer, and the brand's aesthetic pulls from circuit bending, glitch, noise, drone, and electroacoustic traditions. Error Instruments sells directly through its own site as well as Reverb and Etsy, and has exhibited at Superbooth in Berlin.

Error Instruments has 1 product cataloged on Equipboard, including Synthesizers. Their gear is featured by 1 artist, with the strongest followings in Electronic, Rock, and Pop. Notable users include Toshiji Mikawa.