Every turntable needs proper grounding; otherwise, electrical hum may be induced. If a turntable is not properly grounded, it may have a different reference potential than the connected amplifier. Consequently, these potential differences induce a compensating current which can be heard as hum.

Therefore all good turntables have a separate ground cable that can be connected to standard amplifiers or phono stages, which usually have a ground terminal. This way different potentials are equalized and hum is no longer audible. However, many modern amps, especially most amps of soundbars or streaming speakers have no ground connection. These systems are referenced as “ floating mass systems“. If a standard turntable is connected to such a "floating mass“ amplifier, audible hum will be the result.