The Synclavier is an early digital synthesizer, polyphonic digital sampling system, and music workstation manufactured by New England Digital Corporation of Norwich, Vermont. It was produced in various forms from the late 1970s into the early 1990s. Used by many notable musicians, the Synclavier was inducted into the TECnology Hall of Fame, an honor given to "products and innovations that have had an enduring impact on the development of audio technology," in 2004.

The original design and development of the Synclavier prototype occurred at Dartmouth College with the collaboration of Jon Appleton, Professor of Digital Electronics, Sydney A. Alonso, and Cameron Jones, a software programmer and student at Dartmouth's Thayer School of Engineering.

First released in 1977–78, it proved to be highly influential among both electronic music composers and music producers, including Mike Thorne, an early adopter from the commercial world, due to its versatility, its cutting-edge technology, and distinctive sounds.

The Synclavier architecture was based on additive synthesis, with the output of multiple digital sine wave oscillators blended to form complex timbres. The oscillators formed the fundamental frequency along with harmonics or partials. The loudness and envelope of each oscillator could be adjusted using front panel controls. New England Digital Corporation (NED) designed their own 16-bit central processor called Able, a kind of minicomputer. Such an advanced computer was required because digital additive synthesis is computationally expensive. The audible result of additive synthesis was somewhat thin, suitable for steady-state sounds such as vibrating strings: violin, harp, guitar, etc. It was not good at generating percussive sounds with fast transients. To fix this problem, NED also designed sample-based synthesis into the Synclavier, calling it "timbre frame synthesis", and allowed for an optional FM synthesis module. The sampler recorded an external sound and saved it as a sound file. Most of the standard Synclavier timbres were obtained by sampling acoustic instruments or human voices. Four layers of sound files or partial timbres could be blended to make a more complex sound, for instance by adding a percussion sample to three brass instrument samples to get a sharper attack. If the FM synthesis module was purchased, a separate harmonic envelope feature was engaged, and a more dynamic sound could be produced.

Only about 20 Synclavier I models were built. These were sold mostly to universities. The initial models had only a computer and synthesis modules; later models added a musical keyboard and control panel.

The system evolved in its next generation of product, the Synclavier II, which was released in early 1980 with the strong influence of music producer Denny Jaeger of Oakland, California. It was originally Jaeger's suggestion that the FM synthesis concept be extended to allow four simultaneous channels or voices of synthesis to be triggered with one key depression to allow the final synthesized sound to have much more harmonic series activity. This change greatly improved the overall sound design of the system and was very noticeable. 16-bit user sampling (originally in mono only) was added as an option in 1982. This model was succeeded by the ABLE Model C computer-based PSMT in 1984 and then the Mac-based 3200, 6400 and 9600 models, all of which used the VPK keyboard.

Synclavier II models used an on/off type keyboard (retroactively called the ORK) while later models, labeled simply Synclavier, used a weighted velocity- and pressure-sensitive keyboard (called the VPK) that was licensed from Sequential Circuits and used in their Prophet-T8 synthesizer.

The company evolved the system continuously through the early 1980s to integrate the first 16-bit digital sampling system to magnetic disk, and eventually a 16-bit polyphonic sampling system to memory, as well. The company's product was the only digital sampling system that allowed sample rates to go as high as 100 kHz.