Weiss Engineering is a Swiss manufacturer of high-end digital audio equipment, founded in 1985 by electronics engineer Daniel Weiss. The company is based in Switzerland, where all of its products are designed and built. Initially focused on digital signal processing for mastering studios, Weiss expanded into the high-end hi-fi market in 2000.

The brand's pro audio lineup includes mastering-grade tools such as the EQ1 equalizer, DS1-MK3 de-esser/compressor, DAC1 MK3 and ADC2 converters, the A1 monitor controller, and the DNA1 dynamics processor. On the hi-fi side, Weiss produces DACs and digital signal processors including the DAC501/DAC502, DSP501/DSP502, the Helios reference DAC, and the MAN301 music server. Some of Weiss's mastering algorithms have also been licensed to Softube for plugin versions such as the Weiss MM-1 Mastering Maximizer and the Weiss Complete Collection.

Weiss Engineering is widely regarded as a reference for mastering-grade digital processing, and its hardware has long been a fixture in major mastering studios worldwide. Daniel Weiss has received a Technical Grammy for his contributions to digital audio.

WEISS has 4 products cataloged on Equipboard, including Effects Processors, Marching Cymbals, and Preamps. Their gear is featured by 2 artists, with the strongest followings in Electronic and K-pop. Notable users include Deadmau5 and pdogg.