Hi-Fi Parts are components of a high-fidelity sound system. The three crossword solutions for Hi-Fi Parts are Styli (5 letters), Amps (4 letters), and Tuners (6 letters). Styli are the needle-like devices used in record players to pick up sound vibrations from the grooves of a record. Amps are short for amplifiers, which are used to increase the power of an audio signal. Tuners are devices that receive radio signals and convert them into audio signals.