Arcade machines are iconic not just for their gameplay but also for their distinctive sounds. The audio systems within these cabinets have evolved, but several common setups define the classic arcade experience. The most prevalent type is the mono (monaural) sound system. Found in the vast majority of classic cabinets, this setup uses a single audio channel. Sound is generated by the game's PCB (Printed Circuit Board), often through a dedicated amplifier chip, and is routed to one or more speakers wired in parallel. This creates a cohesive, room-filling sound that was cost-effective and sufficient for most games.

The physical speaker setups vary. A typical configuration involves a single, large full-range speaker (often 4 to 6 inches in diameter) mounted directly behind the perforated marquee or lower down in the cabinet. Some cabinets feature two or more speakers, but they are usually still reproducing the same mono signal to increase volume and clarity, not to create stereo separation.

For stereo sound, a different approach is used. This was less common in the early days but became standard for more advanced games in the 1990s. Stereo systems require a PCB capable of outputting separate left and right audio channels. These signals are then sent to two distinct speakers, typically placed on the left and right sides of the cabinet or marquee area. This allowed for directional audio effects, immersing the player in the game's environment. Fighting games like *Street Fighter II* famously used stereo to make characters appear to move from one side of the screen to the other.

The standard for connecting audio (and video/power) is the JAMMA harness. This wiring loom includes pins for a single mono audio output. For stereo sound, manufacturers either used non-standard pinouts or added a separate stereo header on the PCB. Modern replacement boards often provide both mono and stereo output options. Ultimately, whether simple mono or immersive stereo, the sound system is a crucial component that completes the authentic arcade atmosphere.