The Bose 4702 (most commonly found as the 4702-II and 4702-III) is a vintage 4-channel stereo integrated amplifier originally built primarily for the Japanese market. It is highly regarded by vintage audio enthusiasts for its unique flexibility in powering multi-speaker setups, such as the classic Bose 901 or 301 series. )Key Specifications The amplifier features a flexible power configuration. It delivers 50W per channel when operating all 4 channels simultaneously, or it can be bridged to output 100W per channel in a standard 2-channel stereo setupon the Power Warning: 100V AC power. (like the US at 120V or Europe/Africa at 220–240V) requires a step-down voltage transformer to prevent damage.