Typically a preamp is two channel only & will not process surround sound.
Processor is 5 to 7 channels. Processes surround sound.
Receiver can be 2 to 7 channels with preamp and amp combined into one box. 2 channel version will not process surround sound.
Processor is 5 to 7 channels. Processes surround sound.
Receiver can be 2 to 7 channels with preamp and amp combined into one box. 2 channel version will not process surround sound.