Sustainiac, a product of Maniac Music, Inc., is an Indianapolis-based company specializing in electromagnetic sustain systems for electric guitars. Founded by Alan Hoover and Gary Osborne, the company produced its first sustainer in 1986 and has been manufacturing its flagship products since 1987. The technology was inspired by Michael Brook's Infinite Guitar concept and uses a driver installed in the neck pickup position to electromagnetically vibrate the strings, producing infinite, controllable sustain and harmonic feedback effects without the need for high volume or close proximity to an amplifier.

The company's flagship product is the Stealth PRO, a self-contained kit that replaces the neck pickup and fits into standard electric guitar control cavities. The system offers multiple sustain modes including fundamental sustain and harmonic overtone modes. Sustainiac systems are available as aftermarket kits and as OEM installations in production guitars from major manufacturers including Schecter, Ibanez, and Jackson. Schecter offers the widest range of Sustainiac-equipped models across lines such as the Hellraiser, Banshee, Reaper, and Sun Valley series, while Ibanez features the system in Joe Satriani signature models like the JS2480 and JS240PS.

Sustainiac-equipped guitars are used by artists spanning rock, metal, and experimental genres, including Joe Satriani, Synyster Gates of Avenged Sevenfold, Matthew Bellamy of Muse, and DJ Ashba. All Sustainiac products are manufactured in the USA.

Sustainiac has 1 product cataloged on Equipboard, including Electric Guitar Pickups. Their gear is featured by 15 artists, with the strongest followings in Rock, Metal, and Pop. Notable users include Synyster Gates, Matthew Bellamy, and Kerry King.